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Ads28
05-09-2013, 09:35 PM
Was poking around the engine bay a while back and noticed my coolant sensor just didnt look right...I go to pull the plug off and sure enough it was in 2 pieces
http://i31.photobucket.com/albums/c392/Imprezaluver/IMG_0799_zpsb26ab46d.jpg (http://s31.photobucket.com/user/Imprezaluver/media/IMG_0799_zpsb26ab46d.jpg.html)
http://i31.photobucket.com/albums/c392/Imprezaluver/IMG_0800_zps4a66a60e.jpg (http://s31.photobucket.com/user/Imprezaluver/media/IMG_0800_zps4a66a60e.jpg.html)
Ordered one up from Lithiaparts and installed it...Now maybe Ill get a lil better milage ? haha
http://i31.photobucket.com/albums/c392/Imprezaluver/IMG_0802_zps15c1c424.jpg (http://s31.photobucket.com/user/Imprezaluver/media/IMG_0802_zps15c1c424.jpg.html)

93celicaconv
05-10-2013, 12:45 PM
Beside the "happen-chance" visual check to find a broken ECT (engine coolant temperature) sensor, there were no other symtoms (check engine light on, cold start issues, warmed up engine running issues, etc.)? If none of that, I would have some concerns.

Ads28
05-10-2013, 04:54 PM
No check engine light .... Cold start the revs would bounce off 2500 back down to 1500 a couple times ... Warm engine no issues ... Replaced sensor idle still bounces on cold start ... Waiting to see how the milage pans out now

93celicaconv
05-10-2013, 05:24 PM
No check engine light .... Cold start the revs would bounce off 2500 back down to 1500 a couple times ... Warm engine no issues ... Replaced sensor idle still bounces on cold start ... Waiting to see how the milage pans out now

Evidentally, your ECU was getting a resistance value back from the piece of the ECT that had the wiring harness connected to that was neither 0 ohms (short-circuited) or infinite ohms (open circuit) that it did not trip the check engine light. I find that interesting and wonder how that is possible!

Sounds like you cold engine operation did not change with the new ECT installed. This would tell me your warm engine operation was likely in an open-loop mode, running rich. How long do you think the engine was operated with the ECT sensor broken? Just wondering if you CAT is fouled with carbon and perhaps has an elevated back-pressure as a result now.

Ads28
05-10-2013, 10:10 PM
No clue how long...I don't have a car installed .. Surewin header to a monza cat back.. So doubtful high back pressure is an issure haha yeah I'm curious to see what kinda milage I get now ... But I'm still struggling with the high idle issue

First start up usually always has one or more blips of 2500rpm. Settles at 2 then drops down to 1200 as I reach op temp

Ads28
05-10-2013, 11:23 PM
Heres a video of the start up

Ambient temp 6'C

http://s31.photobucket.com/user/Imprezaluver/media/Video_zpsd03f825a.mp4.html
Heres idle a couple mins later
http://i31.photobucket.com/albums/c392/Imprezaluver/image_zps8fd794a3.jpg (http://s31.photobucket.com/user/Imprezaluver/media/image_zps8fd794a3.jpg.html)

93celicaconv
05-11-2013, 12:47 PM
No clue how long...I don't have a car installed .. Surewin header to a monza cat back.. So doubtful high back pressure is an issure haha yeah I'm curious to see what kinda milage I get now ... But I'm still struggling with the high idle issue

First start up usually always has one or more blips of 2500rpm. Settles at 2 then drops down to 1200 as I reach op temp

1200 RPM is quite high for a normal operating temp idle. Depending upon what transmission you have, idle speed should be between 700-800 RPM when at normal operating temperature. What model yeaer is your vehicle, and does it have the original engine? You may have a idle speed valve that can be turned down to get you at the correct idle speed. That early speed hunting is concerning though.

Ads28
05-11-2013, 01:07 PM
90 GTS 2.2 5speed ... Yeah normal idle should be 700ish ...
It has an idle screw on the throttle body and that's tightened all the way ( to lowest idle position )
I've checked for vacuum leaks. Inreplaced the TPS same time I did coolant sensor
I know my car used to idle properly but that was years ago .. It's been high for quite awhile so I dunno what is causing it

93celicaconv
05-11-2013, 01:30 PM
What is causing it is too much air getting into the intake manifold.

That engine is MAP (mean asbsolute pressure) controlled. As such, high idle speeds are always caused by excessive air getting into the intake manifold.

Sources of excess air are:

idle speed valve opened to far (you've verfified this not be the case for you)
vacuum leaks (I know you said you verified vacuum leaks don't exist for you, but did you check things like your power brake booster leaking or any other vacuum line connections to vacuum devices leaking, intake manifold gasket failure, etc.)
throttle plate stop positioned too far out, preventing throttle plate to close properly
IAC (idle air control) valve stuck open or position sensing no longer calibrated properly


I am also still amazed that your broken ECT sensor appears to have had no noticeable effect on engine operation (short term effects, not long term like fuel mileage). Something isn't quite right there either.

Ads28
05-11-2013, 02:02 PM
Thanks for all the input ... Ill search for vacuum leaks again ( I sprayed intake cleaner all over the place listening for any change in the idle and didn't notice anything as well as visually looked the best I could )
Not the throttle.. Thought of that as well .. And checked ( stop is correct , also removed intake tube to visually check the clearance n position of the butterfly valve )
Next would be replaced IAC valve. But that's 200$ Same with the map , soo not so keen to replace those if not needed

93celicaconv
05-11-2013, 02:06 PM
Thanks for all the input ... Ill search for vacuum leaks again ( I sprayed intake cleaner all over the place listening for any change in the idle and didn't notice anything as well as visually looked the best I could )
Not the throttle.. Thought of that as well .. And checked ( stop is correct , also removed intake tube to visually check the clearance n position of the butterfly valve )
Next would be replaced IAC valve. But that's 200$ Same with the map , soo not so keen to replace those if not needed

I wouldn't replace anything unless I knew it wasn't working. Is your IAC valve a seperate body bolted under the throttle body? If so, you can get a couple at a salvage yard for far less than new cost. Camry's had these same engines in the same years. Same for MAP sensors (although I don't think that is what is wrong with yours). You can diagnose a MAP sensor to see if it is a problem, but usually your ECU will tell you that too. The BGB in this forum can guide you through the diagnostics.

Ads28
05-11-2013, 09:13 PM
Yeah I'll have to do some more diagnosing

Just went through the IAC test procedure ...
Proper ohms around 21
Op temp connected TE1 - E1 idle increased for couple seconds then returned to "normal" ( 1200 for me at this point )
So that tells me the IAC is working properly

Tested voltage going to the MAP. It's good 4.9v
I'll try the map tests another day when it's warmer n I feel like digging into the ECM

So I'm leaning toward intake manifold leak of some kind

Ads28
05-14-2013, 02:03 PM
Finally got a full tank in there so well see how the mileage goes ��

93celicaconv
05-14-2013, 03:26 PM
Yeah I'll have to do some more diagnosing

Just went through the IAC test procedure ...
Proper ohms around 21
Op temp connected TE1 - E1 idle increased for couple seconds then returned to "normal" ( 1200 for me at this point )
So that tells me the IAC is working properly

Tested voltage going to the MAP. It's good 4.9v
I'll try the map tests another day when it's warmer n I feel like digging into the ECM

So I'm leaning toward intake manifold leak of some kind

I disagree with the part in red. All you know about the IAC is that the coil is testing good. It doesn't tell you a thing about whether the rod inside there is mechanically stuck.

However, if your cold engine speed is up there around 1,800 to 2,000 RPM, and as it warms up, it comes down to 1,200 RPM, that would tell me the rod in your IAC valve is moving. So if this part is true, look for vacuum leaks in and around the intake manifold (and any vacuum lines and devices attached to it). If your warm engine and cold engine idle speed is about the same, then I would focus on your IAC valve rod being stuck, and it needs to be removed and cleaned and reassembled properly to restore it's movement, or replace it with a known good one.

Ads28
05-14-2013, 03:47 PM
With that test. Doesn't the fact that jumping TE1 and E1 increases the idle ... Mean that the iac is working. And cycling properly ? ... But yes cold idle and warm idle are different so we can rule out the IAC

93celicaconv
05-14-2013, 04:14 PM
With that test. Doesn't the fact that jumping TE1 and E1 increases the idle ... Mean that the iac is working. And cycling properly ? ... But yes cold idle and warm idle are different so we can rule out the IAC

Putting a jumper wire on terminals TE1 & E1 should either have had no observable effect on engine idle speed, or could have slightly decreased engine idle speed (assuming engine was at normal operating temperature). The fact that your engine speed increased momentarily is concerning. Did you verify you got the jumper properly connected by observing your check engine light? When terminals TE1 & E1 are properly connected, your check engine light will flash, either continuously (meaning you have no DTC codes) or with pauses between flashes (indicating a DTC code number or numbers). If your check engine light was not flashing after you jumpered terminals TE1 & E1, you did not have the jumper properly connecting the terminals.

Jumpering TE1 & E1 also strips some of the ECU outputs to allow settings to be made (i.e.; the ECU will not advance timing, so timing can be set at the distributor housing to a specific value / idle speed is not adjusted via the IAC valve so idle speed can be set to the sticker value by adjusting the idle adjustment screw).

Ads28
05-14-2013, 10:18 PM
Ok well here could be the majority of my problem haha I have

Code 12 - Rpm signal fault

Code 31 - vacuum sensor signal vault

Ads28
05-14-2013, 11:18 PM
I just tried resetting the codes... pulled the EFI and Main engine Fuse... reinstalled and let it run for 10 min shut her down..then took her for a boot around the block...Checked again now I have a new code as well code 24 so now I have

Code 12 Engine revolution signal missing

Code 24 Intake air temperature signal fault

Code 31 Air flow meter circuit or Vacuum sensor signal fault

93celicaconv
05-14-2013, 11:26 PM
Well, I only have a few minutes. Judging by what was happening with your ECT sensor, I suspect you have a lot of issues, and in combination, these are probably contributing to your symptoms. With these faults, your ECM is likely operating in an open loop (limp mode). The question is, are all these codes related to a single cause, or are they all independent?

Let's take your code 24 first. Is your intake air temperature sensor (located on the top cover of your air filter box) there? If so, is it plugged in?

For code 31, your engine in MAP (mean absolute pressure), which is the vacuum sensor - you don't have MAF (mean air flow). So, is your MAP sensor (located on the firewall behind the intake manifold) plugged in? If so, is the vacuum line between it and the intake manifold connected? Is that vacuum line open or plugged? Lot's of things to check for here.

Code 12 is pretty complicated. We'll save that for a little later.

Ads28
05-15-2013, 12:08 AM
Code 24... I have a custom cold air Intake...But yes the Intake sensor is Installed into the Pipe between the filter and throttle body..and yes plugged in

31- Yes plugged in, removed the line between sensor and intake ..no obstructions

93celicaconv
05-15-2013, 01:59 AM
You said in post #8 your engine used to idle properly. Was there any event preceding when your idle speed went up that you can recall? If so, what was the event?

Have you ever had any fuse blow from the time your engine used to idle properly until now?

Given what your responses are so far, I'm beginning to think you have a single issue causing all these codes.

Ads28
05-15-2013, 02:22 AM
Never blown a fuse *knock wood* besides cigarette lighter that I know about ....

As for anything happening that may have caused this issue ... I have no clue it's been like this for years ...it's had a high idle longer then it was normal idle soo it's been to long for me to remember any specific event

Ads28
05-17-2013, 11:44 PM
Well went to the scrap yard and swapped out my Map and Intake temp sensor ....no change , same idle , same codes

93celicaconv
05-18-2013, 12:47 PM
Like I said, I think you have a single issue that is causing all your codes, but it was great that you ruled out individual issues as causes (getting replacement parts that don't change anything). I think either your ECU is defective, or you have a wiring harness defect that is causing several wires to be open or short-circuited. All the sensor items your ECU is reporting as having problems are in the same engine wiring harness. It is possible this wirng harness was compromised by being removed and reinstalled, or something got against it and cut/pinched it, causing these problems.

Ads28
05-19-2013, 02:28 AM
Once I have some time ill check wires ... Would suck if the ecu Is toast

93celicaconv
05-19-2013, 11:28 PM
Once I have some time ill check wires ... Would suck if the ecu Is toast

Not at all. You will likely find several of them in local salvage yards.

Ads28
05-20-2013, 11:02 PM
haha not so much...theres only 1...Single..Celica in scrap yards around here..and the ECU is gone :(

93celicaconv
05-21-2013, 12:52 PM
haha not so much...theres only 1...Single..Celica in scrap yards around here..and the ECU is gone :(

There is a 90 or 91 Celica GT-S automatic in the salvage yard by me, at least it was there a couple months ago. I'm going on there this weekend, I could pull it for you if you wish, but this wouldn't be the first thing I would try to replace, as your problem could be in the wiring harness.

Let me know if you want to go this route. I would need your exact year, model and engine/transmission information first.

Ads28
05-25-2013, 12:08 AM
Still haven't check wires. But finally burnt threw my tank of gas ... And I got a whooping 19MPG:ouch:. :( ? ... All city driving. And fairly aggressive driving ( I missed her all winter so of course I drive her hard)

According to fuelly.com I av 21mpg between fill ups. My best ever was 24.5mpg out of 10 fuel ups. So by lookin at fuelly records I'm on the low side of all the 5th gens on there