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You have to pop the purple thing off the bottom of the connector and insert a very skinny tool into the smaller opening near the pin(s) you want to remove. The purple thing comes off by prying it gently from both ends.. it will pop off without too much trouble
There's also a cover on the opposite end of the connector that you may or may not have to pop off (I've seen it missing on a lot of cars for whatever reason). It's already removed in this picture
The wires in the picture are from a 2005, so the colors may be different on yours, but the locations should be the same. The two on the left are the same color and are for the IAT sensor. The other three are for the MAF sensor. Pulling any of the three should do the trick (power/ground/signal)
Did some datalogging today. Here is what I discovered.
Get engine to idle speed around 600 rpm. Foot off of the throttle pedal, ease clutch out to get car moving. Look at absolute throttle position, pedal position, engine speed, and vehicle speed. Here is what I see:
Quite the opposite actually.. If it's supposed to idle around 18% and having to go down to 14% to idle down, then air is getting in from somewhere else.
Like I mentioned earlier, min airflow table sets how far the blade closes most of the time. Once you come to a stop one of the adaptive idle functions kicks in and adjusts the throttle blade as needed.
I'll dig up a log from when I was stock and see what mine idled at TPS wise. I know now it's around 20%.
Last edited by schpenxel; Nov 4, 2015 at 12:34 PM.
Those low LTFT's also indicate to me there's no vacuum leak. Remember ½ the rear of my intake came off so I had a HUGE vacuum leak but the car idled perfectly.
If this car was tuned, this could be explained and fixed in 3 or 4 keystrokes. The fact that it's not tuned and still doing this perplexes me.
So to be clear, it never ran properly with the new throttle body?
Those low LTFT's also indicate to me there's no vacuum leak. Remember ½ the rear of my intake came off so I had a HUGE vacuum leak but the car idled perfectly.
If this car was tuned, this could be explained and fixed in 3 or 4 keystrokes. The fact that it's not tuned and still doing this perplexes me.
So to be clear, it never ran properly with the new throttle body?
That is correct. The new throttle body performed just like the old one that was the original from the factory.
The idle seems to want to find its way back to 600 when the engine is cold. Once it gets to about 200, the idle consistently holds at 1100 till car stops moving.
Quite the opposite actually.. If it's supposed to idle around 18% and having to go down to 14% to idle down, then air is getting in from somewhere else.
Like I mentioned earlier, min airflow table sets how far the blade closes most of the time. Once you come to a stop one of the adaptive idle functions kicks in and adjusts the throttle blade as needed.
I'll dig up a log from when I was stock and see what mine idled at TPS wise. I know now it's around 20%.
If a vacuum leak was occurring, wouldn't the LTFT's be higher at idle than what I am seeing and then drop as engine speed is increased?
Do you have any pending TSB's or recalls on the car, particularly one that would cause the dealer to reflash your computer? This problem could be fixed in the time it's taking me to type this if you wanted to get a tune. I'm wondering if a factory reflash would also fix it.
Read your codes in the computer and post them up.
Then take off the negative battery cable and let the car sit for a minute or two with the door open to really draw it down. Then plug in the cable and go for a drive (and re-index your windows).
I've had to "reboot" my car a couple of times over the years when it was doing odd things. It worked every time. I don't recall a high idle being one of my odd things, but it's not going to hurt.
True.. those fuel trim values do seem fairly low for it to have a vacuum leak..
I looked at a log from mine when it was 100% stock and it idled around 18% TPS reading, which seems to be where yours wants to be until you come to a stop. I dunno.. is there any kind of calibration for the throttle bodies?
Do you know anyone with HP Tuners? This could be fixed, or at least covered up, very easily with that
Last edited by schpenxel; Nov 4, 2015 at 02:09 PM.
True.. those fuel trim values do seem fairly low for it to have a vacuum leak..
I looked at a log from mine when it was 100% stock and it idled around 18% TPS reading, which seems to be where yours wants to be until you come to a stop. I dunno.. is there any kind of calibration for the throttle bodies?
Do you know anyone with HP Tuners? This could be fixed, or at least covered up, very easily with that
I did the idle relearn procedure, but I did not disconnect the battery before doing the procedure steps. I will try the procedure again after disconnecting the battery and see if that makes a difference.
I pressurized the intake through the brake booster line and plugged the intake upstream of the maf body. Air was leaking out of the black pcv unit screwed into the vararam aluminum maf body. Air is leaking out internally not around where it threads into the maf body. Could this be the vacuum leak that is causing the idle problem?
That is the clean air supply for the engine's pcv system, it would be normal for you to hear air going into that port.
You could plug that port from the outside and you should not hear any air leaking. As I believe you do not have a vacuum leak.
Did you ever swap your maf with your buddy and see if that changes anything?
Can you post a picture of where it's leaking exactly?
The leak is at the connection of the black nose that runs from the passenger valve cover to the vararam aluminum maf body. A black part threads into the maf body and that hose snaps onto a stem that swivels. The leak is coming from the stem that the hose connects to. When I remove the hose there is air coming out of the stem. If I plug the stem, air will leak around the stem.
Last edited by stoessjc; Nov 8, 2015 at 02:44 PM.
Reason: added information
That is the clean air supply for the engine's pcv system, it would be normal for you to hear air going into that port.
You could plug that port from the outside and you should not hear any air leaking. As I believe you do not have a vacuum leak.
Did you ever swap your maf with your buddy and see if that changes anything?
With the intake pressurized, air is leaking out of this connection.
He does not think he has a spar one. I have not asked him if I can borrow the maf from his z06.
Plug the connection from outside and do the test again. I bet you won't hear anything. It's normal for this to be an outlet when hooked up it is the fresh air intake for your pcv system.
Check codes and post up. Then unhook your battery and see what happens.
Plug the connection from outside and do the test again. I bet you won't hear anything. It's normal for this to be an outlet when hooked up it is the fresh air intake for your pcv system.
Check codes and post up. Then unhook your battery and see what happens.
The leak is coming from where the tube goes into the main body of this unit. That does not seem normal, as I would think this is a closed system that does not vent or draw air from outside the intake system. Seems is air can leak out of this around that swiveling tube then the engine could possibly draw air in, right?
Sent you a PM.. not going to re-post here but basically PCV system has two pieces.
valley pan-->intake (high vacuum). Sucks blowby gasses, etc. into engine to be re-burned and go out the exhaust/cat converter.
valve cover-->intake tube (low vacuum). Fresh air gets brought in to crankcase through here
Leaks in the low vacuum part of the system should have a much smaller affect than in the higher vacuum sections, there just isn't enough vacuum to pull in much air at that point. That's not to say that can't be it.. I'd try finding a way to make sure that connection is sealed 100% as a test. I dunno.. maybe tape the thing up? It doesn't have to be pretty. If it fixes it, awesome.. if not, at least you know that isn't it
Last edited by schpenxel; Nov 8, 2015 at 10:21 PM.
Sent you a PM.. not going to re-post here but basically PCV system has two pieces.
valley pan-->intake (high vacuum). Sucks blowby gasses, etc. into engine to be re-burned and go out the exhaust/cat converter.
valve cover-->intake tube (low vacuum). Fresh air gets brought in to crankcase through here
Leaks in the low vacuum part of the system should have a much smaller affect than in the higher vacuum sections, there just isn't enough vacuum to pull in much air at that point. That's not to say that can't be it.. I'd try finding a way to make sure that connection is sealed 100% as a test. I dunno.. maybe tape the thing up? It doesn't have to be pretty. If it fixes it, awesome.. if not, at least you know that isn't it
What if I remove the threaded piece from the vararam maf body and thread a plug in place of that piece? It is threaded, so I should be able to find a plug/bolt to seal it. I can just leave the tube disconnected for the short time it takes to test whether that is the source of my problem. I have tried to find that part with no luck. Do you have any idea what it is called or part number?
What if I remove the threaded piece from the vararam maf body and thread a plug in place of that piece? It is threaded, so I should be able to find a plug/bolt to seal it. I can just leave the tube disconnected for the short time it takes to test whether that is the source of my problem. I have tried to find that part with no luck. Do you have any idea what it is called or part number?
If your pcv fresh air supply is leaking, yes that's a problem. You should seal it up somehow, perhaps remove that swivel fitting and plug that hole and drill a new one, or maybe epoxy that one in place (though I would be afraid the epoxy would eventually crack).
You can't just unhook it and plug the hole, the intake manifold sucks air from the port behind the throttle body through the valley pan, and the hose you're looking at is the fresh air supply for the engine. If you leave that fresh air supply unhooked, the engine will be drawing air into itself that is unmetered by the MAF, thus throwing off your fueling and potentially your idle. You must provide metered fresh air to the engine for the system to work properly.
Perhaps you could buy a new fitting from Vararam.
It's possible this air leak right by the MAF is causing your problem. I'm a little dubious but it shouldn't leak, that is for sure.
You could test all of this by installing your stock air cleaner again and see if you still have the problem.
