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Hookecho
03-29-2012, 05:08 PM
Been having issues with my motor for a long time now. I get knock retard between 4000 - 5000rpm. This is every time I boost. Even retarding my base timing to 7*btdc and running 7psi didn't help. The problem is very consistent. It has gotten worse lately to the point where I can here the pinging. So I don't drive the car much unless it's to see if the problem is fixed after troubleshooting. The motor runs perfectly other than that. It is fast and pulls hard as hell.

Myself and Luni have toiled over this for months now and have thrown parts at it until we're blue in the face. I have tried different AFMs, ignitors, spark plugs, wires, distributor, and ECU. The only thing I haven't tried is another coil and injector resistor pack. I run 93 octane and have tried octane booster.

I have tested every single thing I can. Unfortunately I was using a crappy multimeter and my readings were inaccurate. So I went and bought a quality tester and proceeded to check everything again. The only thing I have yet to do is check voltage at the ecu. I ran a couple liters of a mixture of seafoam, water, and a couple tablespoons of 2 cycle engine oil through the combustion chamber to clean any carbon build up. Did this through a small vac line. Back when I changed the HG I cleaned what little carbon there was off of the pistons. I had the valve seals replaced so the valves were cleaned.

The motor is stock gen2. I have roughly 5000 miles on it since the swap 2 years ago. It has a new head gasket, seals, timing belt, plug wires, cap, rotor, and plugs. It has a 2.5in exhaust with a gutted cat. I also have a FMIC.

Here are the results from my testing so far.

Compression test: 172, 173, 173, 173.

Boost/Vacuum leaks: None. I built a leak detector and pressurized the motor until my boost gauge held steady at 15psi. I located a few small hose leaks. I put new clamps on every single hose on the motor. All hoses are new.

Air filter: New

No diagnostic codes.

Spark plugs: Brand new iridiums.

Plug wires: Pretty new. Tested in order from 1 to 4. .62ohms, .81ohms, .9 ohms, 1.1ohms. Got the same results when tested on the distributor cap.

Ignitor: 11.8v with ignition on.

Coil: .8 ohm on primary (Spec is .41 - .50 ohm.) Secondary was 12.83kohm(spec is 13.8)

Distributor cap: Bought a new one last week.

Distributor: NE and G - 198ohm(spec is 180 - 220), G1 and G - 159ohm(spec is 140 - 180), G2 and G - 159ohm(spec is 140 - 180)
Air gap is .2mm

Ignition timing: Dead on at 10*btdc

Mechanical timing: Dead on.

Fuel pressure: base pressure 38psi. 5lbs boost = 44psi, 10lbs boost = 50psi, 15lbs boost = 54psi. Fuel pressure increase steadily as boost increased.

Fuel pump: 255lph TRE pump. Wired in a relay at the pump. I have 14.8v at the pump.

Fuel injector resistor: Spec is 4-6ohms. Mine tested at 6.4 ohms at each wire.

Fuel injectors: Each tested at 3.2 ohms. Spec is 2-4 ohms. Stethoscope says they are pulsing in time with engine rpm.

Fuel filter: Brand new.

AFM: VC and E2 - 236ohm, VS and E2 - 266ohm, THA and E2 - 2.3kohms at 70*F. All well within spec

Coolant temp sensor: New

TPS: Properly calibrated.

Engine Cooling: A fresh flush and fill with a 70/30 mix. Thermostat is not that old, engine temps are normal and never runs hot.

I have yet to test the TVIS

Luni
03-29-2012, 05:20 PM
Id like to chime in on some of this, but we have been testing this behind the scenes together, so I got nothing. I think its time to get some fresh brains on this.

4thgenceli
03-29-2012, 05:32 PM
Remind me again... knock retard is when the knock sensor on the block detects a knock and then it retards the timing to prevent carnage?

Hookecho
03-29-2012, 05:35 PM
Yup

4thgenceli
03-29-2012, 05:41 PM
Initial thought would be how's the sensor, but since you said you can hear it pinging sometimes that means the sensor is doing it's job. Ruled out any bottom end issues? I remember after you installed it the HG blew shortly after.

Anything strange showing in the oil?

Hookecho
03-29-2012, 05:43 PM
Oil is clean. I have several knock sensors for testing.

4thgenceli
03-29-2012, 05:50 PM
Oil is clean. I have several knock sensors for testing.

I'm out then :P

sloceli
03-29-2012, 07:23 PM
I'm going to guess that it could possibly be your injectors not providing enough fuel. The 4-5k rpm range fuel maps are rather lean to start with. Take a look at my dyno and you can see the afr go lean from 4-5k. I'd pull you injectors and send them to witch hunters for cleaning.
http://www.celicatech.com/gallery/files/9/0/489LSQ.jpg

Funkycheeze
03-29-2012, 08:06 PM
Do you have any EGT/AFR information from driving or dyno pulls?

I'd pull the injectors and get them bench flow tested.

Luni
03-29-2012, 08:30 PM
Im gonna send him a set of injectors that came off my MR2.

I was running a 20b, 3 inch exhaust, intercooler, and 17 PSI on 91 octane at 4200 feet. If I had enough fuel for it here, he should there.

Bruce, Im going to hold off on sending you the Water Injection kit. I found all of it but the relays. Im going to go locate those injectors and that coil and Im gonna send them to you.

l0ch0w
03-29-2012, 08:41 PM
My first suggestion would be for you to replace your plug wires with brand new OEM ones.

Not for the reasons you suspect though... Bad plug wires introduce a TON of EMI which can cause false knock readings if your shielding is compromised in your knock sensor wiring.

Ohming plug wires out is not indicative of the condition of your wires... it just isnt. If you want a more detailed description for why I can explain it to you, but it would take up quite a few lines.

I can make you a patch harness for your knock sensor if the plug wires dont fix stuff PM me...

Also, your coil is out of spec? why havent you replaced it???

I have one of those too if you need...

donteatbugs
03-29-2012, 09:39 PM
I have part if you need them, would take like 1 day to get to you. Or you could bring your car over and I can fix it for you. either way.

Funkycheeze
03-29-2012, 11:32 PM
If he is hearing the knocking, I don't think it is the sensors themselves, or the wiring.

Regardless, one thing I have done in the past to combat oversensitive knock sensors (expecially in engines reuiblt with forged pistons and tight tolerances) is to install the sensors with a good few wraps of PTFE pipe tape. Helps to dampen transients that can set the sensors off.

CollapsedNut
03-29-2012, 11:35 PM
You let Murg drive it. Nuff said.

Hookecho
03-29-2012, 11:35 PM
I do have a set of oem wires that are relatively new. I was running them all while having the knock issue. I bought a set of Bosch wires to troubleshoot with because they are cheaper than oem. I have read a lot about plug wires and I know that the cheap low resistance wires have less windings.

As for the coil I'm waiting on one to arrive.

Hookecho
03-29-2012, 11:50 PM
Would a bad injector resistor pack give me these issues.

rizin
03-30-2012, 12:35 AM
A higher resistance would cause for a weaker magnetic field that is created to open the injector. To low it will burn up the drivers in the ECU. That is about all I can say about that. When you getting a wideband O2 setup?

The Captain
03-30-2012, 04:00 AM
+1 on wide band.

ChrisD
03-30-2012, 05:31 AM
Have you tried a new knock sensor? Failing that, sounds like youve tried near everything. I might be inclined to send the injectors to witch hunter. i've sent a few sets to them and have been surprised at some of the variances that were there.

Sent from my Transformer Prime TF201 using Tapatalk

joe's gt
03-30-2012, 06:07 AM
I echo finding out what your AFRs are. You are striking out blindly until you have real time some sensing equipment that shows what your fuel and ignition is doing. You say you think you are hearing the detonation. Have you pulled your plugs and looked for the typical signs of detonation. That would confirm that you are indeed detonating and the knock sensor is functioning correctly. Have you pulled bearing caps to check for scoring on the bearings or journals?

Hookecho
03-30-2012, 01:16 PM
That's what gets me. My plugs show no signs of detonation. They(NGK BKR7E) did have whitish colored ground straps at one time but I cleaned the strap, ran them again, and they showed signs of normal combustion cycles. I then bought some iridums(BKR6) and after checking them yesterday they show signs of normal combustion. I haven't looked at my bearings and I doubt I will bother at this point. I have scoped the cylinders and everything looks normal from what I can actually see with a scope. No pitting or any damage on the dome or crown area. No scaring on the cylinder walls. FWIW

The thing is this. I have never heard detonation on any vehicle I have ever owned. So I can't say foe sure that's what I'm hearing. What I have heard many times before is valvetrain clatter. That is the same noise I am hearing from my motor. What is odd is that I hear the clatter(that I assume is detonation) at 3800rpm but I never get knock response when I hear the clatter. The knock retard comes on 500rpms afterward. Sometimes I have heard the clatter at around 5500 rpm and got no knock retard at all.

Anyway, yeah, it's been hard to diagnose this one. I wish I had a wideband but I don't. I should have had one long ago.

As it stands right now I will try another coil and injectors. If that fixes my issue then I will send mine to Witch Hunters. If not then I will continue my endeavor.

Hookecho
03-30-2012, 01:32 PM
I have tried different knock sensors Chris but not brand new ones. I actually had one go out a couple of weeks ago as soon as I left the driveway. It's the 3rd KS I've blown in the course of 2 years. The first time was when a large rock fell of the back of a truck and my right front tire struck it causing a loud ping as it blew the tire and hit the wheel. The 2nd time was when I was cruising at normal throttle and had not boosted for a while.

Hookecho
03-30-2012, 02:40 PM
This is a picture of my ngk bkr7e when I inspected them a month ago after hearing what I thought was detonation. I have always done these inspections as a routine. This was the first sign of whitish colored ground straps. All 4 plugs looked exactly the same.

http://www.celicatech.com/gallery/files/4/1/4/3/imag0089.jpg

http://www.celicatech.com/gallery/files/4/1/4/3/imag0090.jpg

This is a picture of my Iridiums when I inspected after installing them. This is after several boosted runs on the highway. All 4 plugs looked exactly the same.

http://www.celicatech.com/gallery/files/4/1/4/3/imag0092.jpg

I cleaned the ground strap then went for a long drive without boosting. At the end of my drive I did a few hard pulls. All plugs looked the same.

http://www.celicatech.com/gallery/files/4/1/4/3/imag0099.jpg

I cleaned the plugs and reinstalled them. A week later I went for a drive where I didn't get in the boost for about 30 minutes. Then I did some wot pulls. When I pulled the plugs they looked normal. No signs of running lean or hot.

These are the iridums I have been running for the past few weeks as of 20 minutes ago.

http://www.celicatech.com/gallery/files/4/1/4/3/imag0109.jpg

http://www.celicatech.com/gallery/files/4/1/4/3/imag0111.jpg

http://www.celicatech.com/gallery/files/4/1/4/3/imag0112.jpg

Mafix
03-30-2012, 05:31 PM
take the plugs out and install bkr7e plugs at .028 gap.
have you replaced the knock sensor wire?
also check the turbo and be sure the shaft is not hitting anything. you are overheating the hell out of those plugs. both sets.

Hookecho
03-30-2012, 05:40 PM
I did check the turbo a couple of days ago. There was very little side to side play and no play at all when pulling the shaft in and out.

What could be causing my plugs to be overheated? Maybe my motor is running hot and I don't know it. I can't imagine it being charge temps.

Hookecho
03-30-2012, 06:44 PM
I know this is far fetched. Could having lower intake temps mask the fact that my coolant temps would be higher than normal? Say if I had a problem with the motor overheating, installed a fmic, and it lowered the overall temperature in the motor. Could there still be hot spots around the cylinder walls from a deficient cooling system?

Reason I ask is because I took the car for a drive a while ago. Parked in the shop and grabbed the upper radiator hose. It was hot as hell. The lower radiator hose was just barely warm. Maybe I found the issue, idk. I know that I have a stuck thermostat though.

Funkycheeze
03-30-2012, 07:58 PM
the stock toyota temperature gauge has a big dead band around the normal operating temps - so you could be running a little hot and not know it. Cooling issues can definetly cause knocking.

Mafix
03-30-2012, 10:04 PM
indeed, fix that thermostat, stat!

rizin
03-30-2012, 11:05 PM
Hook pm me your address i will send you my wide band setup. You just have to get it back to meat the dragon or mail it. Won't be able to send it untill tomarrow.

Hookecho
04-02-2012, 05:03 PM
Well, I don't think the thermostat is my problem. I bought a new one. Placed both the old and new one in boiling water. They both opened up fully. I read in the BGB that coolant flows back into the motor through the lower radiator hose. That would explain why the lower hose doesn't get hot. Fail

Mafix
04-02-2012, 07:07 PM
true but a bad thermo is a bad thermo.
do you have a cat converter on your car?

Hookecho
04-02-2012, 11:00 PM
I don't have a cat.

New thermostat didn't help.

Thanks to Rizin I have a wideband to troubleshoot with. I installed it today and went for a ride. After letting the motor warm up I left home and cruised for 10 minutes. Then did some wot pulls. My AFRs were 18 at idle. As soon as I start boosting they jump to 13. At 10psi its at 13.9 . At 14psi they are at at 14.9. At wot the afr will jump between 14 an 15.5. Between 4000 and 5500rpm AFRs stay well above 14. I seen a couple of spikes at 15.4.

CollapsedNut
04-02-2012, 11:19 PM
You don't have a knock problem, just a retard problem ;)

Funkycheeze
04-02-2012, 11:40 PM
That is waaaay too lean. No wonder you are having knocking issues.

You said you did a fuel pressure check already, I'd check or just change the filter if it isnt newish and get the injectors tested ASAP.

CollapsedNut
04-02-2012, 11:42 PM
I told you to dump more fuel at it months ago, shoulda listened.

Hookecho
04-03-2012, 12:12 AM
Well, the filter is new. I'm hoping that the injectors a to blame.

T-spoon
04-03-2012, 03:29 AM
I'm a little surprised it even wants to idle at 18:1. Is the stock O2 plugged in and working? If so, I'd think the ECU would add fuel, no reason you should be running out at idle and cruise. WOT is totally different. Doesn't make a lot of sense to me, even if the injectors are bad, it's odd. Your spark plugs all looked relatively the same, it'd be even more peculiar to have all four injectors doing the same wrong thing.

temperacerguy
04-03-2012, 03:55 AM
Damn, that is LEAN... The pic of your plugs shows lean for this motor... if you are on stock ECU, the 3S is a rich motor, and there should be grey/black soot on the insulators.

I would check fuel pressures. a bad regulator can cause this problem. as well as low pressure from the pump. a pump goiing out may be able to provide the volume, but not the pressure required for full fueling.

Nevermind... I see you already checked pressures... Then the next culpret is the fuel injectors themselves... replace, or have professionally cleaned and flow tested.

Luni
04-03-2012, 07:50 PM
He has good pressure. Im sending him my MR2s Gen2 fuel rail complete with injectors. It worked perfect when pulled, so it should take care of that for him if thats it.

Mafix
04-03-2012, 08:23 PM
i can't believe that your car is stil running. this is a known good sensor on the wideband?

Funkycheeze
04-03-2012, 08:31 PM
The TCCS can only adjust the fuel quantity so far based on O2 sensor input. So if it is way lean (or rich) it can only help to get the A/F ratio closer to where it needs to be.

donteatbugs
04-03-2012, 08:32 PM
I would change your filter too. You can test good pressure when the engine is at idle but can starve at the high end if there is a restriction in the line.

Hookecho
04-03-2012, 08:54 PM
The filter is new. I've changed it 3 times in the past year and a half.

I took voltage readings on the O2 sensor earlier. I tested it at the check connector and got 0v. No fluctuation at all. Just to be sure I tested it at the ecu and sensor itself. Still 0v.

Each injector harness had 11.88v as did the coil and ignitor.

rizin
04-03-2012, 11:11 PM
3 years ago when i pulled it out of my car after a couple weeks of running it. It was good then. Plastic protector and bagged and boxed for the last 3 years.

Hookecho
04-04-2012, 12:06 AM
I have a thread up on MR2OC also. One of the guys over there had me test the o2 sensor. Here is what he said about the test.


I tested the O2 sensor. I get a reading of 0v. It doesn't fluctuate at all. So I'll need to buy another one.


Not so fast.

If that's the case and the stock narrowband doesn't fluctuate at all, it confirms the reading of the wideband being overly lean. If the mixture were correct, the NBo2 would fluctuate as the ECU tries to maintain 14.7.

I was suggesting this test as a means to make sure the wideband was reading correctly. It looks as though it is. Sometimes there are ground potential issues with widebands where they will read incorrectly because the ground they're attached to is floating somewhere above actual chassis ground.

It could be an issue with the airflow meter itself.
It could be a leak somewhere between the AFM and the turbo.

A leak on the output side of the turbo would manifest itself as leaner at idle, but going very rich under boost as you're blowing out air the ECU already added fuel for.

I'd say some sort of restriction in the fuel system (filter, etc) but that would manifest itself more so at higher demand and be mostly non-existent at idle. You're lean across the board.

Do you have a spare fuel pressure regulator you can crush to bump base fuel pressure up to 50-55psi? That would at least get you some more fuel to see if it makes a difference...


Also, if the NBo2 is pegged at 0v, you *should* be getting a CEL for it. If you're not, it suggests there is something causing the ECU to not go into closed loop (so it would never read the O2 and see the problem).

So from what we gather the o2 is reading 0v because my AFRs are so lean. I had a spare o2 from my 5s that I installed and it also read at 0v.

I had continuity between the ECU and plug for both the o2 and AFM. I had to stretch 8ft of wire to do the test so all resistance values were around 1.7ohms.

Hookecho
04-04-2012, 12:13 AM
The TCCS can only adjust the fuel quantity so far based on O2 sensor input. So if it is way lean (or rich) it can only help to get the A/F ratio closer to where it needs to be.

What's TCCS?

Hookecho
04-04-2012, 01:28 AM
Based on my fuel pressure readings is it safe to say that the regulator is functioning properly?

T-spoon
04-04-2012, 01:48 AM
TCCS is the computer. And see that's what I think is so whacky. It shouldn't have any trouble idling at 14.7 if it's able to add enough fuel to be under 16:1 at WOT if restriction is the issue. Something just doesn't add up.

celica9303
04-04-2012, 02:34 AM
Have you checked the fuel rail itself? I'm assuming so.

Hookecho
04-04-2012, 04:27 AM
I've checked pressure at the rail.

celica9303
04-04-2012, 04:59 AM
Not pressure I mean for gunk Inside......

Facime
04-04-2012, 08:32 AM
if my logic serves me well you have a dead O2.

Hookecho
04-04-2012, 12:52 PM
That's what I thought too. The BGB says 0v means the o2 is sensor is bad.

Hookecho
04-04-2012, 04:44 PM
I took my other AFM and turned the spring gear counter clockwise 7 teeth. The motor started idling at 12afr instead of 18. I drove it around for a while and it stayed around 14.7 when cruising. When boosting the AFRs stayed in the 11.6 - 12.9 range give or take. I was able to get a reading from the o2 sensor also.

donteatbugs
04-04-2012, 04:57 PM
so WIN?

Hookecho
04-04-2012, 06:10 PM
Idk. I wouldn't think that adjusting the AFM like that would be the right way to fix the issue, but more of a band-aid fix. I guess it's possible that I have two bad AFMs. It makes better sense than having 4 bad injectors. I still need my AFRs to be in the 10s though. Which would require more adjustment.

Funkycheeze
04-04-2012, 08:23 PM
18:1 AFR at idle is strange - the narrowband O2 will only flutctuate around 14.7:1, and doesn't provide feedback at WOT condition, so I would rule that out. I was thinking more like a single stuck injector - but compromised flow on all or a few of them would definetly show up less at idle.

A bad AFM seems like a good candidate - no way to resistance check the flapper door system?

Hookecho
04-04-2012, 09:10 PM
. I'm sure the afm was the problem. I have it adjusted and I'm running 11.5afr through the entire rpm band at 15lbs boost. I just drove it for 40 minutes and hammered on it. Afr at cruise is at 14.7 but idle is 11. The motor feels so Damn responsive and pulls smooth and hard. Never pulled timing once.

Facime
04-04-2012, 09:11 PM
Seems odd that if the O2 was dead that it isnt throwing a code. And now that you got a reading out of it maybe its not totally dead just underreporting? While they can be tested I rarely find it worth the effort and just replace them when they are suspect. I usually have several spares floating around in the parts bin.

also have you backprobed your ecu for baseline voltages? (FI29 in BGB). It might point you in a direction. It took me doing that test on a mk2 Supra to determine that someone incorrectly crossed a TPS wire with a IAC wire (both were brown and in the same loom).


I see you posted at the same time. Thats good that you got that much sorted out. Im still a little suspicious that your remedy is only masking the real problem. Might be worth getting another stock unaltered AFM and see if it reverts back.

Hookecho
04-04-2012, 11:27 PM
I'm hoping another AFM will tell the tale. For right now I can only assume that both of my AFMs were bad, idk. I'm really baffled by this whole thing.

Idk, if richening up the AFRs by adjusting the AFM points toward a faulty AFM or is just masking the real issue.

T-spoon
04-05-2012, 02:31 AM
Damned AFMs.. I thought you were going to ditch the darned thing a long time ago? :hehe:

Hookecho
04-05-2012, 02:47 AM
I'm ready to ditch the whole damn car.

The Captain
04-05-2012, 02:33 PM
Make you a hell of a deal on a GT4.

donteatbugs
04-05-2012, 02:46 PM
Are you sure your TPS is going to idle when the throttle is closed? Have you reset your ecu since messing with the afm?

CollapsedNut
04-05-2012, 02:58 PM
I say if it works now, ride it.

Hookecho
04-05-2012, 03:18 PM
Are you sure your TPS is going to idle when the throttle is closed? Have you reset your ecu since messing with the afm?

I adjusted the TPS to spec. I will go double check. Every time I work on a car I disconnect the battery cable.

MrWOT
04-05-2012, 03:40 PM
I'm astonished you aren't missing chunks of piston if those wideband readings were correct.

You should also run a dedicated ground from b- and solder to the o2 body

Hookecho
04-05-2012, 04:31 PM
TPS is properly calibrated. Just checked it.

donteatbugs
04-05-2012, 08:33 PM
So when it comes off idle the AFR jump up to 14.7 even free reving the motor? Personally I would drive it like it is unless it becomes a problem. My car idles about 11-12 afr because that is as low as my injector will go.

Hookecho
04-05-2012, 08:39 PM
Yeah, as soon as I come off idle it goes to 14.7 and stays there until I boost. Right now it idles at 11.7

Funkycheeze
04-05-2012, 08:40 PM
It really doesn't sound like an O2 sensor problem, as the symptom was bad operation (knocking under lean condition) while running in open loop mode. I would drive it as-is now.

A good case for reccomending the use of wideband on any modified car.

Hookecho
04-05-2012, 08:44 PM
Yeah, like I told Kendall, I've learned my lesson. I've accomplished more in 2 days with a wideband than I have in a year.

Facime
04-05-2012, 10:03 PM
its good to see this FINALLY getting some resolution. If altering the AFM gets you in that kind of ballpark and it remains consistant then I dont see a problem with it.

It would still drive me nuts that I knew that, and I would still be looking for a definative answer, but thats just me.

T-spoon
04-06-2012, 02:43 AM
Just curious, were/are you running an EGT gauge? AFRs like that would usually make you run super hot, which tips you off even if you don't have a wideband. I think they're a great thing to have in combo with a wideband, too.

donteatbugs
04-06-2012, 02:28 PM
I would check the IDL wire from the harness to the ecu. It still sounds like your ecu doesnt think the car is at idle. Or you could try adjusting it out of spec while the engine is running and see if it changes your afr any.

Hookecho
04-06-2012, 03:42 PM
I'll check the IDL wire.

Luni
04-06-2012, 08:12 PM
Do that!

Facime
04-06-2012, 08:55 PM
I would check the IDL wire from the harness to the ecu. It still sounds like your ecu doesnt think the car is at idle. Or you could try adjusting it out of spec while the engine is running and see if it changes your afr any.

This is why I suggested before to backprobe the ECU for voltages. Having done it several times for different toyotas now, anything oddball electrical and its the FIRST place I start now. Honestly, what good is it to test a component (TPS, AFM, IAC, etc) first? You sometimes dismiss a part as good when it tests ok but if its not getting to the ECU correctly how will you know? This can lead you down continual dead ends.

In my earlier example the two wires crossed in my supra between the TPS and the IAC would not throw a code because they approximated each other, but at inappropriate times.

Hookecho
04-07-2012, 02:55 PM
As I suspected the adjustment made to the AFM was only masking the problem as my AFR climbed back into the 15's again while in boost. So I will be changing out the injectors, rail, and FPR to see where that gets me. The injectors will get new seals and o-rings.

CollapsedNut
04-07-2012, 03:35 PM
www.mrinjector.us is an awesome injector guy. Priced good and the service is amazing. He will actually call you back if you leave a message!

T-spoon
04-09-2012, 06:24 AM
As I suspected the adjustment made to the AFM was only masking the problem as my AFR climbed back into the 15's again while in boost. So I will be changing out the injectors, rail, and FPR to see where that gets me. The injectors will get new seals and o-rings.

I really don't think that's your problem, but hopefully it is since that's what you're doin :)

Hookecho
04-09-2012, 04:13 PM
What's your theory?

I'm going to finish testing at the ecu tomorrow. I personally think it's electrical.

Hookecho
04-09-2012, 04:18 PM
and has something to do with the signals from the AFM.

I hope...

alltracman78
04-09-2012, 06:21 PM
This is why I suggested before to backprobe the ECU for voltages. Having done it several times for different toyotas now, anything oddball electrical and its the FIRST place I start now. Honestly, what good is it to test a component (TPS, AFM, IAC, etc) first? You sometimes dismiss a part as good when it tests ok but if its not getting to the ECU correctly how will you know? This can lead you down continual dead ends.
This is EXACTLY what you should be doing when you have a problem.
Start by checking the signals at the ECU. Testing parts usually isn't conclusive, this way you know which signal[s] are off.

Hookecho
04-12-2012, 04:31 PM
So adjusting the AFM to richen AFR's was a band-aid.

After back pinning the ecu I found low voltage at IDL and VTA. IDL is supposed to be 4.5v - 5.5v and it read .26v. VTA is supposed to be 3.7v - 4.5v and it read 2.2v. I had 5v on VC so I knew the output signal to the TPS good. I had a spare TPS that tested with the same readings. Ben had me build a jumper harness from the ECU to a separate TPS plug so that I could test the TPS again and rule out bad wiring. I got the same low readings again so I went to PaP and found a couple of TPS's off of a 5sfe. They are different part #'s but it's what I had. I tested both of them and they read 4v on the VTA wire but still had .26 on the IDL wire. Odd

Anyway, I set the AFM spring tension for the flapper back to it's factory posistion and installed the 5sfe TPS. The damn car is running great now. My AFR goes to 12.5 when I start boosting and drops to around 10.7 at full boost. AFR maintains at stoich when cruising and so far idles at stoich now. I'm afraid to get my hopes up but I guess time will tell.

So apparently the ECU reads the throttle angle to control timing or fuel trim at WOT, idk. All I know is that it works so far.

donteatbugs
04-12-2012, 04:48 PM
YAY! glad that 45 minute phone call worked for something.

4thgenceli
04-12-2012, 05:11 PM
Woot.

Now keep it running.

Hookecho
04-12-2012, 05:40 PM
Now to get the A/C working right. Push come to shove I'll just wire in a switch to activate the clutch but I'd rather do it right.

donteatbugs
04-12-2012, 08:00 PM
I have the auto air amplifier from my alltrac if you want it.

T-spoon
04-13-2012, 01:14 AM
Told ya it's not the fuel system! (< pretends to know something) :hehe: Glad it's running well :)

MrWOT
04-14-2012, 07:27 PM
So apparently the ECU reads the throttle angle to control timing or fuel trim at WOT, idk. All I know is that it works so far.

Yeah, the TPS is how it calculates load. Glad you found the problem before something went pop.

Hookecho
04-16-2012, 04:48 PM
Well, It's still running great. When I go into boost the AFR shoots into the 11s then 10s. It has been nice to feel the full power of this motor and all the way to redline too.