I decided that my other thread in the general section wasn't helping me much because it has nothing to do with my current problem and I wasn't getting much help out of it. So I just went through swaping my new CT onto my 7M and I checked out everything from vaccum lines to intercooler pipes. Everything was actually going really well untill it came time to start it up for an oil change... well I accidentaly tried starting it twice with the AFM unpluged and it dyed just as fast as it ignited. So I plug her back in an start her up just fine. Once everything was back together I took it for a ride through the neighborhood and noticed a strange bogging at about 1200 rpm and the check engine light was on... I check the codes and came up with 31 and 24 wich im told only happens when your AFM has a bad connection. So i cleaned the contacts and cleared the codes then started her up. And now it idles fine for about 20 seconds and bogs down till the engine stalls. I'm told this is caused by a vaccum line or IC pipe but i cant find anything wrong, no pin holes... nothing and I have no error codes now. All my lines are the same as before I started this swap and before it drove great and boosted to 5psi wich it currently is still only boosting to. HELP lol
Bogs at Idle and stalls
- Thread starter DigityD'87
- Start date
Mine started doing the same thing after I installed my neo, but only sometimes. It seems to be only when it gets cold(below about 65) or really humid. The neo has helped track what may be happening because it shows if the signal is there. At idle the signal disappears but once the throttle is pressed, the signal comes back and it boosts to 11psi just fine. I have cleaned the connections several times but that doesn't help. I think what may be going on is the afm might have a little bit of buildup on the sensor causing the low air velocities to not register. I just haven't had the time yet to check. I will also try changing the afm electronics if cleaning doesn't help.
Sadly I have never had this problem. I check everything before I start the car, and then everything is great.
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CPT Furious;1283510 said:
Yeh, I know that now. Those codes have nothing to do with my current problem. I need to figure out why my car idled fine before the turbo swap but doesn't now.
92TealSupra;1283439 said:
You can reset the codes by pulling the efi fuse in the main fuse box. Pulling the battery cable will reset the radio and other things that may need power for memory.
I don't think resetting the ecu will solve the problem. It is either the afm or a leak in the piping.
I had another experience similar where the hose at the outlet of the turbo popped off and the car would idle low but would accelerate very roughly up to about 1500 then bog down. The turbo(not oem) would start moving air so the computer would start putting in more fuel causing it to run really rich. Of course the check engine light was on the whole time.
Hope that helps
Man i see im not the only have this problem when it fully warms up it never stays at 1k it slowly bogs down to about 500-700rpm ....i have no vac. leaks ..so i feel ur guys pain Have u Touched ur idle screw on the intake?
All the intercooler and vaccum are fine. But I did just realize something however. When I was burping my coolant I had the front of the car jacked way up in the air (obviously) but my gas tank was almost on empty. Is their any chance my fuel filter needs to be changed in order to fix this? It's probably a good idea anyway but my Hayne's manual says a dirty fuel filter might cause the engine to stall. If so the filter is located above the gas tank correct?
DigityD'87;1284125 said:
under.. u can't get to it from the trunk .... u gotta get under the car between the 2 rear tires by [the diff.] [[[it's hideing]]]
It is possible the fuel filter is clogged. Usually it affects the engine under high fuel demands first the works its way down to idle. If the car sat up for a little while when waiting for the turbo then it can clog while sitting. If you have been driving it, you would notice it under full throttle/boost first. It is mostly load oriented not rpm oriented. It is a good cheap thing to try. Easy to change. If you have a fuel gauge, you can hook it up and see if the pressure drops when you throttle the engine.
A little antidote: I had a local guy ask me what to try on his supra (slightly different problem). I told him to try the FF before anything else then come back and see me if it didn't fix it. Three months later he comes back to me and said that was it. He had just replaced it the prior week after trying other BS that I said it would not be and would be a waste of time changing them. I told him to listen to me. Long story short, After several more times, I refuse to help him b/c he won't listen to me! HA!
A little antidote: I had a local guy ask me what to try on his supra (slightly different problem). I told him to try the FF before anything else then come back and see me if it didn't fix it. Three months later he comes back to me and said that was it. He had just replaced it the prior week after trying other BS that I said it would not be and would be a waste of time changing them. I told him to listen to me. Long story short, After several more times, I refuse to help him b/c he won't listen to me! HA!
noel;1284122 said:
Idle is 700RPM and trying to adjust it by messing with the throttlebody is the wrong way to go about it. Idle is controlled by the IAC valve, the throttle body is supposed to be closed.
To the OP, what exactly did you change? What codes do you have now?
Poodles;1284489 said:
That's just it man.... I didn't change a thing and I don't have a single code. On top of that, I checked every vaccum line and IC pipe and came up with nothing. The only thing i did was try to start the car with AFM unplugged on accident and I ran it while jacked up in the air for 15-20 with a low tank of gas, which is why I thought my fuel filter might be causing this considering i've never changed it in the year i've been driving it (and highly dout the previous owner did either).
Poodles;1284489 said:
Yeah...
The 86-88 have an idle speed adjustment screw on the throttle body. It allows air to bypass the throttle valve and it IS designed to be adjusted. The 89+ do not have this(from what I've seen). Most toyotas from this era have this idle air bypass screw, even my 92 22re pickup, for some reason they didn't put it on the 89+ supras. They probably tried to make the idle more stable in varying conditions.
It only bogs then stalls at Idle. Like when I'm stopped at a red light, I have to hold the gas in a bit just to keep it running. Other than that it's perfectly fine.
No, the screw is on the later models, and it's NOT meant to be messed with (hence why it doesn't have any coverage in the TSRM and why they capped it on the later models).
Trying to raise your idle like that will only cause the ECU to try and fight it with the IAC.
Back to the issue of stalling, did you put gas in it?
Trying to raise your idle like that will only cause the ECU to try and fight it with the IAC.
Back to the issue of stalling, did you put gas in it?
I always thought the tsrms are very incomplete for a novice mechanic. They are designed for a certified and/or experienced mechanic. They give you the specifics on each car that would otherwise be left to guess. It tells you the idle rpm but doesn't tell you how to adjust it because that is general knowledge for anyone with a little experience with toyotas or even general efi systems. From my experience, the ecu does not fight idle adjustments using the screw. In fact there is no change in the isc when adjusting the screw. I set my idle at 800 when opp temp is reached because I like my idle to be a little higher.
DD: If there are no codes and the car runs normally at open throttle, try adjusting the idle screw out to maintain a good idle speed. Also do a compression test on all your cylinders. I can't help but think how delicate the head gasket is on these motors.
DD: If there are no codes and the car runs normally at open throttle, try adjusting the idle screw out to maintain a good idle speed. Also do a compression test on all your cylinders. I can't help but think how delicate the head gasket is on these motors.
OP: Rather than argue with Mr. General Knowledge and A Little Experience I'll simply state he has NFI what he's talking about. Leave your idle bypass fully seated where it belongs...
jetjock;1284738 said:
Since you are the named official expert here, why don't you explain how it really works rather than just saying what is wrong. I can't speak for others, but I am here to learn. I'd rather know how it really works than just belittle others without the fancy 'titles' that were labeled to certain members(with all due respect). Give us something other than NO.