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Hookecho
02-09-2011, 09:18 PM
How often do you guys notice your timing being pulled?

Under what conditions does it usually happen while you're driving?

The reason I ask is because it seems to happen quite often with me. It seems to happen in the higher rpm range. I'm not sure exactly what is causing it. I have the LED knock detection so when it happens I can tell right away. I don't necessarily feel it but the red LED doesn't lie. I changed to NGK BKR7E's this morning and took a run at 15psi. I got timing being pulled at 5000rpm in 2nd gear. I then switched back to low boost at 12psi. I didn't attempt a run a 12psi so I don't know if that helped.

What other conditions does the ECU pull timing other than knock. I know that my LED's will indicate timing is being pulled until the motor reaches operating temp. After then I can boost with no problem, mostly.

So I'm guessing that coolant temp, intake air temp, and knock detection have to be withing certain parameters or the ECU will pull timing.

The only thing I can figure is heatsoak. Which is odd being that it is cold outside. Another thing I have noticed is that my coolant temp sender is acting up. When I get in the throttle my temp gauge will sometimes drop all the way to cold. When I ease out of the throttle it will jump back to reading a normal temp.

I have a stock motor and TMIC. No catalytic converter and 2.75in exhaust. BKR7E plugs, new wires, cap and rotor. All vacuum lines are new. All couplers and clamps are new. Boost is set at 12psi on an EBC. The motor is very healthy. It cranks up fast and purrs like a kitten.

When I replaced the head gasket during the swap I noticed that the pistons had very little carbon on them. I cleaned that off. I don't think it's a detonation problem. The old plugs looked good when I changed them this morning. Only had about 1500 miles on them but they were the BKR6E's and I wanted to try a colder heat range.

ChrisD
02-09-2011, 09:31 PM
Weird. What octane fuel do you use?

If the ECU sees a really cold signal from the coolant temp sensor it will definitely retard timing. Fuel pump is up to spec?

Hookecho
02-09-2011, 10:50 PM
I use 93 octane and the fuel pump is a new TRE 255lps.

Hookecho
02-09-2011, 11:48 PM
Fuel filter is new too. Timing is at 10*btdc.

ChrisD
02-10-2011, 04:31 PM
Well, first step might be to check the water temp sensor. Check the wiring for connectivity and connection at the plug.

Facime
02-10-2011, 06:09 PM
Yeah I would check both temp sensors against the resistence at temp charts. Might be a good idea to get a compression reading and see if you have any unusually high numbers. Is the car in question MAF or MAP? If Maf then you might want to resistence test the AFM and double check you arent getting a pirate air leak. Also are you running an oil catch can, if no, when was the last time you cleaned the IC?

Without making any other changes, you could try running some octane boost or mixing in some race/AV gas and see if it helps reduce the incidence.

ChrisD
02-10-2011, 06:55 PM
Out of curiosity have you checked the ECU for any stored codes? Maybe something like a knock sensor acting up.

v8killer
02-10-2011, 07:31 PM
yeah if your on basically stock with the stock turbo there should be no issue to run as low as 91 california octane and up to 17 psi assuming a fmic. but if your at 12 psi and the tmic and getting knock there is a fault somewhere. keep in mind that the stock 3sgte ecu takes timing off after 6000. it could also pick up valve train noise check your oil level? also remember that the stock ecu is knock limited as in it sets the timing by sensing the right noise to dictate how much advance it will give. thats why you get more performance just by putting in higher octane fuel. some cars get very little gain because their ignition maps are not knock limited. i guess that was useless info. even having something loose in the right spot can cause stupid things to happen with all the old sensors and old harness.....

ChrisD
02-10-2011, 08:34 PM
Keep in mind he has a JDM ECU and TMIC ATA IC.

Hookecho
02-11-2011, 01:36 AM
I checked compression a few months ago and it was good. I think it was 180/180/183/181.

I do have a new coolant temp sensor that I can install. I'll check the wire on the one that operates the temp gauge. My temp gauge needle sits a quarter way from the left when tue engine is at operating temp.

I have never cleaned the Tmic and there is some oil in it.

I'm going fill up tonight and use octane boost. If that don't help then I may have a rattle somewhere causing false knock. I had that problem before with the intercooler cover but fixed it.

Hookecho
02-11-2011, 01:41 AM
Is it true that jdm ecus are tuned for higher octane than the 93 that I am using. I've read where some folks have no problem using 91/93 and some have to use higher. I know my crappy narrow band a/f gauge shows I'm running nice and rich at wot. So I wouldn't think that's the case.

No codes on the ecu.

v8killer
02-11-2011, 02:50 AM
they use the research octane number "RON" we use r+m/2 the octane is really close just that for some reason its cleaner there there is no gain by using a jdm ecu. the maps are identical.

v8killer
02-11-2011, 02:51 AM
oh and the rc is the one that has more hp and different maps.

alltracman78
02-11-2011, 09:13 PM
You really need to check where you get your info. This isn't the first time you've posted completely wrong info.

The JDM ECU is tuned for higher octane than the US ECU. It also has a higher HP number [when it's not pulling timing].
US 200
JDM 225
non JDM homologation 204
JDM homologation [RC] 235

RON and MON are 2 different octane readings [very close though].
Japan just uses RON, the US uses an average of both [RON + MON/2]. RON 98 [what is normally available in Japan] is roughly RON+MON/2 95 IIRC.

Using the JDM ECU on 91 or 93 US octane will usually cause the ECU to retard timing. How much depends on the outside temp, engine condition, ect.

ChrisD
02-11-2011, 10:08 PM
People run on 94 here, with zero issues.

And yes v8killer your info is dead wrong.

At this point I'd probably suggest going with investigating that coolant temp sensor. One other thing, what spark plugs are you running? If stock you might benefit from going one step colder. I like the NGK BKR7EIX.

Facime
02-12-2011, 01:51 AM
One other thing, what spark plugs are you running? If stock you might benefit from going one step colder. I like the NGK BKR7EIX.

from his original post

I changed to NGK BKR7E's this morning and took a run at 15psi.

Hookecho
02-12-2011, 05:09 AM
a $5 bottle of octane boost and a full tank of gas seemed to fix it. I haven't tried to boost higher than 12psi yet. I've only done a few hard pulls through all gears but so far it's not pulled timing. I'm going to get in the throttle at 15psi tomorrow and see what happens.

We'll see what happens throughout the next couple of days.

Hookecho
02-12-2011, 05:12 AM
Chris, I'm using the V powers NGK BKR7E's. I was using the BKR6E platinums.

ChrisD
02-12-2011, 02:22 PM
Sorry, I read that too, my memory span isn't that great clearly. :hehe: I wonder if the gas you have is just, just on the threshold for minor knock. On your next tank you could try setting the base timing to 9 degrees which might take care of it?

Hookecho
02-12-2011, 03:29 PM
Thanks Chris. I'll try that.

T-spoon
02-13-2011, 06:05 PM
I had my 90 'trac pull timing more than once in Houston. The a/a tmic is just terrible in that kind of climate. The time it did it the worst was Kroger gas (was SUPPOSED to be 93 octane, but after stopping and dumping a can of octane booster in I was able to drive it home at least, I won't touch anything but Chevron or Shell now). It did run kinda like poop though on warm days, and was really only what I'd call peppy on cooler nights.

MrWOT
02-14-2011, 11:19 PM
Knock sensors are the devil in my current opinion. Or until false positives are elimiated, which I haven't seen yet. I simulate the one in my GS, but I'm absolutely sure that I'm within my octane requirements. I didn't use one on the 165 either with the microtech ECU.

If you want a fairly cheap per gallon octane booster. The lucas upper cylinder lube/injector cleaner. NOT the lucas octane booster. Buy it in the gallon, and buy a onetime use bottle, fill little bottle from big one and keep in glovebox. :) The gallon costs me ~$30 and treats ~400 gallons of gas. Not bad $/gal.

From my oberservations, it actually works better than their red bottle octane booster :hehe: I imagine whatever oil they use as a cylinder lube impedes the flame expansion. It is a non-solvent. I've done a seafoam style treatment with it before ;)

ericfragola
02-15-2011, 04:56 PM
If that don't help then I may have a rattle somewhere causing false knock. I had that problem before with the intercooler cover but fixed it.

are you saying that when your intercooler cover rattled, it picked up on the knock sensor and it ppulled timing?

im having this issue as well, when i get up in the high rpms its not smooth. the timing gets pulled randomly and i hate it...and my stock 185 TMICcover IS loose, just plopped on there. ill bolt it on today and see what happens.

ChrisD
02-15-2011, 05:06 PM
Yeah that could definitely happen. The stock knock control isn't smart enough to differentiate between a vibration and actual knock a lot of the time.

This is one of many reasons I just ditched the stock ECU in the end... :hehe:

ChrisD
02-15-2011, 05:07 PM
Yeah that could definitely happen. The stock knock control isn't smart enough to differentiate between a vibration and actual knock a lot of the time.

This is one of many reasons I just ditched the stock ECU in the end... :hehe:

ericfragola
02-15-2011, 05:14 PM
i guess i can spend a couple minutes bolting the cover on instead of half assing it and plopping it in :P hopefully that solves the problem. it happened alot in 5th gear when i opened it up on a straight away to try and figure out what was wrong.

Hookecho
02-15-2011, 05:57 PM
Any rattle registers as knock.

ericfragola
02-17-2011, 05:37 AM
I have the LED knock detection so when it happens I can tell right away.

what exactly do you mean by LED knock detection? just an LED light that flashes when the sensor picks something up?



oh! and also, taking off my loose tmic grill did the trick. timing no longer gets pulled...so simple yet so frustrating.

Hookecho
02-17-2011, 05:49 AM
Crazy ain't it.

Here's the led knock detection mod.

http://www.celicatech.com/forums/showthread.php?20309-DIY-knock-detection-system-AKA-TVSV-LED&highlight=tvsv%20led