1996 Buick Skylark Rough Idle

FARMER1009

MEMBER
1996 BUICK SKYLARK
6 CYL
FWD
AUTOMATIC
95,000 MILES

I have a 96 buick skylark with the 3100 v6 in it. I recently blew the lower intake gasket, and had to replace it. Since I put the car back togethor it idles very rough. It seems like it is missing at idle, but all plugs have spark. The exhaust smells like gas which tells me that it is running very rich. I tried to hook my engine scanner up to the port, but the port appears to not be working. I have replaced with new parts the following sensors and components; ECM, EGR valve, coolant temperature sensor, idle air control valve, and fuel pressure regulator. None of those components seemed to make a difference. Is there anyway to read the engine codes manually, and what do I need to look for to fix the idle problems. Also the motor does not knock or have a stuck valve ticking.

3 Replies

RASMATAZ

MECHANIC
75,992 POSTS

Look for vacuum leaks and check fuel pressure. Is the firing order correct?

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Monday, July 28th, 2008 AT 1:50 PM

FARMER1009

MEMBER
3 POSTS

The vacuum lines are all new, and in the correct position. The firing order is correct, and I checked the timing today. All of those are fine. The engine only runs poorly when idling under 1000 rpm. As soon as the engine RPM's hit 1k they engine smooths out. This car has got my baffled, and it has taken a week to work out. I also need to know how to fix the obd port to where the scanner reads on it. The scanner works fine on other vehicles, and is a snap-on engine scanner.