Wierd problem after TB and MAF install

posjr

Registered User
The main problem was the idle. Idle goes up to 2500 than slowly back done.But took for ever. Unpluged the IACV and no difference car still had high idle than drops to narmol idle. TPS is at .97v. TB plate was adjusted with .010 gap than one full turn. Idle screw all the way closed.

So i tried resealing the IACV since they sent me the wrong gasket and used my old one. And i put gasket maker on it. Nothing Still the same.

Than i tried Blocking the IACV with a plastic card. Car now runs good but the idle screw is still closed and car idles and drives fine. You would think it would die with idle screw closed.

So i thought it was the MAS and added the stock one back on no difference.

I'm very lost. This is a PP 75mm TB, Mark VIII 80mm MAS. I'm thinking at this poing it mybe the TB not seal good. So later i will rip the TB out and re seal it
 
wouldnt u think it was that MAF thats not calibrated to run in your car ?

are u resetting the battery everytime u swap these parts out ?
 
wouldnt u think it was that MAF thats not calibrated to run in your car ?

are u resetting the battery everytime u swap these parts out ?

Yes i reset the battery after every try. And it did it with stock MAF. It has to be some where with TB.

The car idles right now at 1100 with IACV blocked and Idle screw all the way closed. At idl i'm getting 20-21 pressure.

Also the damn TB sticks. Twice already at WOT. It sticked for about a sec.
 
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Ok here is the latest if someone what to share my headache....

Took everything apart. Tb has all seals. But the butterfly looked wrong. There was a gap all around. So i sand a little and realigned it. Not it has a good seal and less sticking.

So at this point now. Car drives fine with IACV disconnected. But hard cold starts. Idle at 800-900 rpms with 21 PSI vac.

With IACV connected. Idle at 1200-1400 with slow drop in idle to 1000.
This is all with Idle screw closed and TPS at .97 which i just checked again.
I'm thinking at this point something my have got in the intake when porting or cleaning the oil build up and my have got stuck in the egr port which my be making the egr stay open.

I feel like throwing a smoke bomb in the intake and see what happens :rolleyes:
 
What your experiencing is dashpot adjustments in the EEC. Essentially this controls how fast the car comes down from being above idle to idle, and the higher the rev the longer it takes to come down. Some cars have done this when they have upgraded the MAF etc.

You have significantly increased the amount of air going into the motor when its reving, and you haven't told the EEC what to do with it.

Sounds like chip time to me.
 
Ok i found the problem.

I pressurized the intake side. With a block off that i clamped to the hose with a hole in the middle. Than pressure it up and use soap and water.

Will the leak was at the tps adjustment sleeve. Crazy leak. But there is no gasket that goes there. So i'll use some gasket maker. And should slove all my problems.
 
I'd be surprised if sealing the vacuum leak solves your problem. I installed a 75mm TB and 76mm MAS (everything else was stock). I had the same exact symptoms you're experiencing to include poor throttle response. I tried all the sampling tubes, sealed all vacuum leaks, set TPS voltage to recommended voltage, battery reset procedure only to experience the same symptoms. I put the 70mm TB back on and the C&L recommend sampling tube. Voila! Runs like a champ. If you keep your combination you'll need a chip. That's my experience.
 
I'd be surprised if sealing the vacuum leak solves your problem. I installed a 75mm TB and 76mm MAS (everything else was stock). I had the same exact symptoms you're experiencing to include poor throttle response. I tried all the sampling tubes, sealed all vacuum leaks, set TPS voltage to recommended voltage, battery reset procedure only to experience the same symptoms. I put the 70mm TB back on and the C&L recommend sampling tube. Voila! Runs like a champ. If you keep your combination you'll need a chip. That's my experience.


Damn same thing. I dont belive it. I checked it and for sure there is no leaks. Still has a funky idle. I'll make a video tonight. :D

It idles at 1000-1100 but hangs at 1300 for a good 30sec before drops.
 
Check tps again. Let the butterfly slam shut a few times to verify that it ALWAYS returns to .97. Sounds way tps related.
 
well check it out when your membership comes thru

I read it. My buddy Dan the man gave me the detials. I'm going to try to close the butterfly more. Than i found another leak last night and it was on the lever side which you cant seal on the tb. I should have took pics.

Its not sticking nomore at half throttle which is good.It seems like a big leak too. When i pressured it late last night you can hear it loud. Mybe i'll take a video of how bad it leaks. Ant this is with only 8lbs of pressure on the intake side.
 
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