That is incredible. I never had to continue to rev and not stop with a tap of the pedal.
I am perplexed!
Unique high RPM at idle
- Thread starter jwilkinson01
- Start date
That is incredible. I never had to continue to rev and not stop with a tap of the pedal.
I am perplexed!
The O2 reading in dash command is anywhere between.1 and .85 while idling
Last week I had a high idle issue after having a dead battery from leaving the dome light on over night. I charged the battery, and drove around as usual for a day and everything was normal. On day two I noticed the idle speed was above 1100rpms, I was thinking a vacuum leak or IAC but for kicks I disconnected the battery for 30 minuets with both cables touching. After 30 minuets I hooked everything back up and the idle returned to normal. Easy fixes don't usually happen for me but that day the stars aligned.
I’ve disconnected the battery. I did the ECU reset process. After the ECU reset it did start off normal at 800 but then after a few minutes, it was back up at 2100.
I just put the old TB on and it’s sitting as a steady 700. Same gasket, same sensors. Hell, everything’s only finger tight Because I expected to pull it right back off
Now the question is why is the larger TB causing the problem?
@SkylinesSuck I think you said you were running the same throttlebody as I am. Did you have any issues with the idle when you installed it?
I sent an email to Bruce over at F&B, Don’t expect a response today because of the holiday but hopefully tomorrow maybe he has some insight
Now the question is why is the larger TB causing the problem?
@SkylinesSuck I think you said you were running the same throttlebody as I am. Did you have any issues with the idle when you installed it?
I sent an email to Bruce over at F&B, Don’t expect a response today because of the holiday but hopefully tomorrow maybe he has some insight
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Again, most of the parts lists are WRONG. Looking up that PN online gave me "Crankcase Vent To Air Cleaner Tube" which is also WRONG for the rear. But don't believe me nor the parts lists - inspect it and you'll know in short order - far faster than fiddling with the IAC.
Thanks Zorba, I pulled both front and back to compare, the front is wide open the rear isn’t. Here’s a shitty pic of the rear
I would pull the air intake tube at the throttle body and inspect the throttle body butterfly make sure it is closed ( very small gap to walls) if that is ok. Remove the idle control and inspect an measure the pintle to see if it is seating all the way. ( if you can get a good measurement) I see you put in a IAC, check the service manual if there is a calibration when a new one is put in. If you can look at data on your scan tool look at the commanded IAC value if available
You say you swapped back to the original TB and that fixed it, but I see you swapped back to the original IAC and it fixed it. I suspect bad new IAC. Did you ever run the new TB with the old IAC?
Sorry for the confusion, let me break it down:
New TB old IAC = high idle.
New TB new IAC = high idle.
Old TB old IAC = runs perfect.
Hmmmm, that's weird then. I didn't have any issues per se. I had/have an occasional hanging idle around 1000rpm, but it's PCM related. I don't think a vacuum leak would present like that either. They are usually high idle at first then slow down a bit as the IAC tries to bring down the rpms. Do you have a way to monitor the IAC steps?
I think you answered your own question. Run the old TB and IAC. You have an issue with the new throttle body. Could be the taper where the IAC seats in the throttle body. The mounting distance between the mounting and taper seat of the IAC. You may have a butterfly or throttle shaft binding hanging the throttle open. If you can read the pids with a scan tool look at the IAC to see if you can read the duty cycle or percentage, if you see it trying to close all the way but you still have a high idle it is probably mechanical not in the electronics
I didn’t swap the TB till this morning, that definitely isolated the issue (post 26).
I will have to see if I have access to the IAC data, I might need something better than what I have now which is just a cheap Bluetooth dongle and DashCmd. I don’t know if there’s a better app for iPhone
Inspect the gasket to see if you are getting a leak past it into the bypass circuit.
I think I used HP Tuners to check mine. I think you'd need something like that.
F&B responded to me late yesterday, they want me to send them the TB for troubleshooting. It is the 70mm.
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