Anyone In The Dfw Area Help!!!

[92GNZ28]

I bought my '87 GN about a year ago and the motor had a rod knock. I knew this already and had a new motor built. It has Champion Irons, PT-52, PTE Front Mount, Delphi 50's inj., Accufab 65mm TB, Poston almost stock cam, Poston Headers, Poston 93 chip for the 50's inj, Pat's 10" 3200 L/U converter..

The problem is the idle. This car won't idle worth a sh*t. Hunts and surges, acts like a vaccuum leak, but trust me I have done everything to find one, work at a dealership and have used the smoke machine numerous times, replaced ALL hoses, IAC sensor, etc. The car has never had anywhere close to 17 in. of vacuum @ idle. The most I can get is 10 in park, in drive drops even lower. Thought I found the problem a couple days ago, thintake manifold gasket seemed to be leaking. Replaced it and still hunts all over the place, replaced EGR valve, no change. I can't get the IAC to drop down to 15-20 counts with the idle srew in or out all the way. Unplugged the IAC and seems to run a little better. Also didn't throw a Check engine light while the sensor was disconnected. Car runs fine at anything over idle. Will surge anometimes stall coming to a stop.. . . I'm at my wit's end here, car is making me lose my mind!!! Only other thing I can maybe hear is a slight exhaust ticking from pass. header somewhere. HELP ME PLEASE!!

 

[TURBOTWIN2]

What kind of scan tool data are you getting from the MAF, TPS, CTS, etc. Not leaking past the throttle body shaft bushings? Possible ground problem? Have you tried a known good MAF or ECM? PCV valve good, I mean really good? Lab scope the TPS for a glitch (more like an old Ford problem)? Maybe one injector dripping and not spraying? Technician B says "Burn the Bitch!" Just kidding, I feel your pain. That low vacuum bothers me. Possible collapsed lifter? Check the rockers. Intake valve sticking open? Maybe run a compression test, wet & dry. I know I'm missing something, let me know. Goog luck.
Added: purge valve at the canister? one hose would be dripping wet with gasoline. Possible mis-timed timing chain?

 

[92GNZ28]

Using WinALDL right now. THere is a Bypass instead of a PCV valve. THis was installed when I bought the car. The low vacuum is bothering me too. Even when I first got the car, before the new motor and everything, it still only pulled about 10 in of vacuum. Has me stumped!!

 

[TURBOTWIN2]

Same vacuum, different engines? That's wierd. Same valve train? You've tried different gauges, right? Try isolating or plugging all the vacuum lines, one by one. Sounds like maybe late ignition timing, crank sensor/cam sensor adjustment? Put a timing light on it and see where it reads at idle and 2500 rpms.

 

[Danster]

There's a couple of places you can take the car to. One being, Richardson's Import Auto, Adi Glatz is the owner, the other is International Motorcars, Jack Laswell is the owner. Both own GN's/T-types and both know the cars.

Or you can come to the first meeting of the year for the Lone Star Performance Buick Club (LSPBC) to be held this Saturday at PaPa's BBQ off Northwest Hwy and Loop 12. The meeting will be starting at 1:00 PM. Many guys that know these cars will be there, guranteed!

Dannyo

 

[92GNZ28]

Where should the timing be at, at idle and 2500? Yes I have a diff. boost gauge in it now than when I bought the car. I have new valvetrain, new lifters, pushrods and T&D Roller rockers. I have heard of the PCV bypass causing problems with vacuum w/o a PCV valve. Is this true haven't tried that yet.

 

[2QUIK6]

Didn't mention what cam was put in during the rebuild??
Come out to the LSPBC meeting this Sat as Danny mentioned above, someone there can steer you in the right direction or at least be able to lend you some spare parts because you go buying new stuff only to find out it didn't cure the problem. Thats what is great about a local car club, you'll meet tons of folks in your area with the same car and spare parts

 

[GNcamino]

What's PaPa's BBQ address?

I'm still figuring out where all these highways go to! Man, I am excited to finally meet other performance Buick nuts!

 

[2QUIK6]

I'm still figuring out where all these highways go to! Man, I am excited to finally meet other performance Buick nuts!

Its on Northwest Hwy between Stemmons Frwy (Loop 12) and I-35E. Its just north of Texas Stadium. From Texas Stadium on Loop 12, exit NW hwy and turn right, Papas will be right there on your left hand side. They have covered parking for your car to boot!

 

[92GNZ28]

well I checked some things and reset my cam sensor and it seemed to help slightly, but still surges at idle badly.

 

[suicide six]

Check inlet tube/hose between MAF and turbo for leaks,esp at alt bracket area.this area may not show up w/smoke test.

 

[fast86gn]

I'm still figuring out where all these highways go to! Man, I am excited to finally meet other performance Buick nuts!

Steve, it great to meet you at the club meeting on Saturday. Just wanted to say welcome!

 

[TrboHead]

THere is a Bypass instead of a PCV valve. THis was installed when I bought the car.

Try a PCV (GM). Put it back stock and disconnect the bypass. This is a metering devise and the stock IAC relys on it.

Larry