Thanks! I did not know that. Good info for me! 
I'll be working on the car next Saturday so after that I will post an update.
I'll be working on the car next Saturday so after that I will post an update.
Bad idle when warmed up
- Thread starter Back2Basics
- Start date
Okay so today we worked on the supra again.
what we did:
- Replaced the afm with ANOTHER one.
- Replaced the iscv with ANOTHER one.
- Checked the cps
- Checked the wiring of the wideband sensor
- Checked the tps AGAIN
- Checked some more sensors. pulled random sensors to see if the engine changed the rough idle but to no avail.
- Raised fuel pressure.
-Checked the ground points.
-Changed the spark plugs.
All things not in this particular order
nothing helped...
what we did:
- Replaced the afm with ANOTHER one.
- Replaced the iscv with ANOTHER one.
- Checked the cps
- Checked the wiring of the wideband sensor
- Checked the tps AGAIN
- Checked some more sensors. pulled random sensors to see if the engine changed the rough idle but to no avail.
- Raised fuel pressure.
-Checked the ground points.
-Changed the spark plugs.
All things not in this particular order
nothing helped...
Oh I almost forgot:
- Changed the coils.
Anyway I slept on this problem for a night, and I think I just might call my toyota dealer and order new sensors for ECT and Cold start.
Hell maybe even the other sensors that are on the car and might break.
- Changed the coils.
Anyway I slept on this problem for a night, and I think I just might call my toyota dealer and order new sensors for ECT and Cold start.
Hell maybe even the other sensors that are on the car and might break.
Vork I think I'm heading right up the same alley your in. I just got done this weekend checking all that I thought I should as well and my idle is still crap when it warms up. I do have a code 51 which I got from messing around with the tps, but I didnt have it before and it was still idling bad. I took the tb off so I can really get the tps set correctly.
I have another idea, but it doenst really make sense with the whole "idling bad ONLY when warm" idea. I've got the stock elbow>3"dp>3"test pipe>stock 2.5" piping the rest of the way back. Its got that one resonator still back there. Now there is a big exhaust leaking by the test pipe. Is there anyways that due to the smaller 2.5" piping, and the resonator, that there could be a small amount of backpressure being built up? Then when enough pressure is there, it kind of pops open by that exhaust leak and is let out right there??? I'll admit, this doesnt really sound correct, but if you understand what I described above and the way I hear this popping happening, it sounds like that could be the problem. Any questions or want something cleared up, let me know.
I have another idea, but it doenst really make sense with the whole "idling bad ONLY when warm" idea. I've got the stock elbow>3"dp>3"test pipe>stock 2.5" piping the rest of the way back. Its got that one resonator still back there. Now there is a big exhaust leaking by the test pipe. Is there anyways that due to the smaller 2.5" piping, and the resonator, that there could be a small amount of backpressure being built up? Then when enough pressure is there, it kind of pops open by that exhaust leak and is let out right there??? I'll admit, this doesnt really sound correct, but if you understand what I described above and the way I hear this popping happening, it sounds like that could be the problem. Any questions or want something cleared up, let me know.
Dark,
If your car was to be an NA the backpressure would have mattered. Turbocharged cars are all about getting the exhaust gasses out asap.
Anyway I have a 3" Elbow-->2.5"DP and 2.5" for all the rest of the exhaust piping and no leaks so I doubt that is the problem.
For me, i'm going to get me some other sensors, another ecu to test and if neither helps me on my way i'll be pulling the whole engine wiring harness and replace or fix it.
If your car was to be an NA the backpressure would have mattered. Turbocharged cars are all about getting the exhaust gasses out asap.
Anyway I have a 3" Elbow-->2.5"DP and 2.5" for all the rest of the exhaust piping and no leaks so I doubt that is the problem.
For me, i'm going to get me some other sensors, another ecu to test and if neither helps me on my way i'll be pulling the whole engine wiring harness and replace or fix it.
Yeah I know you WANT zero back pressure on turbocharged cars, but would those little restrictions cause some?
jetjock said:Lol, nah. I've bit on this guy's hook before. That and the "find more posts by" function shows some folks simply can't be helped. Feel free to learn this lesson for yourself though
This guy should be banned. He is not helping at all now.....
Yeah, ban my ass so I won't need to read posts from idiots like you. Haven't you noticed certain people quickly stop receiving responses from the most knowledgeable here and that you fall into that category? Are you that clueless? The truth is some people just can't be helped. Dark006 is as technically inept as they come and you ignore valid advice while displaying massive ignorance about how the car works. This in spite of having a service manual. Moron.
a_sesshoumaru said:
Yes he should be banned.
Ban that asshole jetjock. He gets pissed off after helping someone who doesn't have a clue what he's talking about.
Forget about all the knowledge and time put in this forum by him.
Forget about the fact that he does help other people and gives good info.
dude...get a life.
jetjock said:
Are you serious?? Why dont you look a little harder at some of the other questions people post and knock them as well then. I know people always say this, but aren't automotive forums a place for the technically inept? You really want members steering away from here dont you?
Last edited:
New update!
Yesterday we took an air compressor and we pressurised the hardpipe system.
Turned out that NONE of the t-bolt clamps kept the couplers tight. We couldn't get the pipes to hold more than 3psi.
We replaced them with normal clamps until the whole system could be pressurised and it was clear to us that this was our problem.
Well, after starting and warming up the engine it turned out that the problem was still there. OH NO!
Now we replaced the ECT, which did not help. We could have also swapped out the CSI timing sensor but it became more and more clear to us that not the sensors but something else was wrong. But what?
Replaced the wideband sensor for my normal and old (but functioning) O2 sensor just to see that that also didn't make the car run any better.
The only thing in the efi system (aside from the ecu) we did not replace yet was the CPS. So we went ahead and swapped it out for another one.
After starting the car immediately ran much better. At last!
After some more warming up and revving the engine it has an a/f of 14.7 so that's really good. The only thing is, sometimes (a few times a minute) it suddenly raises the a/f to about 12, the engine 'sputters' , and after that it returns to normal duty and runs at 14.7 a/f ratio.
So it seems there were at least 3 or 4 problems. One was some wiring which was repaired weeks ago. Another was the hardpipe set and now it turns out that my cps was (most probably) also bad.
The next thing we need to know is why it starts to sputter and run rich for a few seconds every minute. once that's sorted the car will run perfect and clean.
Any suggestions? thoughts?
All info and hints are more then welcome.
Yesterday we took an air compressor and we pressurised the hardpipe system.
Turned out that NONE of the t-bolt clamps kept the couplers tight. We couldn't get the pipes to hold more than 3psi.
We replaced them with normal clamps until the whole system could be pressurised and it was clear to us that this was our problem.
Well, after starting and warming up the engine it turned out that the problem was still there. OH NO!
Now we replaced the ECT, which did not help. We could have also swapped out the CSI timing sensor but it became more and more clear to us that not the sensors but something else was wrong. But what?
Replaced the wideband sensor for my normal and old (but functioning) O2 sensor just to see that that also didn't make the car run any better.
The only thing in the efi system (aside from the ecu) we did not replace yet was the CPS. So we went ahead and swapped it out for another one.
After starting the car immediately ran much better. At last!
After some more warming up and revving the engine it has an a/f of 14.7 so that's really good. The only thing is, sometimes (a few times a minute) it suddenly raises the a/f to about 12, the engine 'sputters' , and after that it returns to normal duty and runs at 14.7 a/f ratio.
So it seems there were at least 3 or 4 problems. One was some wiring which was repaired weeks ago. Another was the hardpipe set and now it turns out that my cps was (most probably) also bad.
The next thing we need to know is why it starts to sputter and run rich for a few seconds every minute. once that's sorted the car will run perfect and clean.
Any suggestions? thoughts?
All info and hints are more then welcome.
man i have been having this exact problem....most noticable after the walbro install...changed afms checked timing redid wires...same old. i think it all started from when i changed to cps awhile back ago...any ideas
808mk3: change the cps again?
For my own problem:
The very bad idling is now almost gone. Only thing is now it is running rich as hell. a/f of about 12.5 ot 13 @ idle and cruise.
What could be the problem?
For my own problem:
The very bad idling is now almost gone. Only thing is now it is running rich as hell. a/f of about 12.5 ot 13 @ idle and cruise.
What could be the problem?
haha yea idk...the reason why i didnt yet because this one looks brand new...my other one that was in the car those wires are all messed up...
thevork said:The very bad idling (bouncing up and down from 12 to 19 and vice versa ) is now almost gone due to the CPS change.
Only thing is now it is running rich as hell.
a/f of about 12.5 ot 13 @ COLD idle and (cold and hot) cruise.
Warm Idle is still very lean, about 17.5 AF ratio.
So the good thing is it stopped going nuts, but another problem arose (or maybe I only solved one of many problems
Any suggestions? I'm having a replacement ECU and AFM sent to me right now so I'll test that AGAIN also.