Low idle in drive w/o AC on it stalls

1qwik99

Registered User
Ok so I've been chasing this problem for about 6 months now. Replaced fuel pump, filter, IAC, TPS. I got the car to idle fine until it warms up then in traffic, AC off, she may or may not stall. So, I watched some YouTube videos and it seems that I might have a vacuum leak but nothing really indicates that from my vacuum readings. I decided to invest in a DIY smoke machine. After hooking it up and 30 seconds later, I see smoke pouring out of the side of the TB where the gasket is supposed to be, and a small stream of smoke coming from the brake booster vacuum valve. I removed the TB and the gasket appeared to be OK, but was flat and very brittle and tore when I tried to remove it. Waiting for parts. Anyone else have this problem?
 
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Good evening


I would check the basic.


- Pull codes.

- Check the DIS heat sink compound.

- Check the fuel pump relay and connector socket for security and or corrosion.

- Check the fuel pressure regulator and vacuum line. Check for cracked vacuum line and or indication of fuel leakage (smell).

- Check the charcoal solenoid vacuum rubber lines for external deterioration damage.



Good Luck.
 
TB leak

After introducing some smoke in through the rubber intake hose, I noticed the smoke exiting the side of the TB where it mounts to the intake you know, where the 4 nuts mount it. I am assuming that the gasket is bad on the left side where the smoke was shooting out. I have the www.redlinedetection.com adapters to block off the intake hose while introducing the smoke so pressure is building in the system.
 
Seems odd the gasket would fail like that, but let's hope it's that simple. Good luck.
 
TB leak

Where it mates to the intake or where the throttle plate shaft bearings are....?

here are some pics of where I believe the smoke was coming from. I may have to use some dye in the smoke if a new gasket does not fix the leak. DSCF1137[1].jpgDSCF1136[1].jpg
 
Is there a gasket inside the throttle shaft? How does that come apart?

Good pics, thanks.

As noted, there are seals, but I've heard some leakage is normal.

How many miles on the TB? Is it original? The screws that hold the plate to the shaft are staked, I think, so they won't risk coming out and feeding into the engine, so I'd not take it apart without good cause. See if you can detect excess side/side play in the bearings...does the TB bore where the plate sits show signs of hanging up or rubbing?

But again, unless you find the bearings to be wasted, I'd not worry about leaks there too much. Just be sure to inspect the TB carefully.

Ken
 
TB vacuum

The TB looks nice and tight no sticking. I did clean it and scrubbed the carbon off the butterfly. I decided to run another smoke test taking the brake booster valve out of the equation because I know it is leaking. I stuffed some rags into the intake (where the TB would go) and put the smoke through the brake booster hose. I found a nice size leak in a vacuum hose directly below and behind the where the TB mounts. So, I think I found the main leak. I'll include some pics later.

Hoping that solves it, finally.
 
TB Leak

Here are some pics of the leaky hose, the diaphragm that is also leaking a tiny amount. Third picture is the new hose I installed. Anyone know what the diaphragm is called and how to pull it?

DSCF1141[1].jpgDSCF1140[1].jpgDSCF1139[1].JPG
 
Tb

I was afraid of that. I think I'll wait on that and see how she does with the leaks I already fixed. Since I haven't gotten an EGR code yet. I put a vacuum gauge on the EGR and it does leak down a little bit over time.

Thanks KMT
 
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