Re: 535 running very poorly PLEASE HELP (archive)

The sticky injector idea is just an hypothesis. Anyway, to see if any one injector is sticking, the spark plug for that cylinder will be coated in black, powdery carbon. If it is wet, then smell it for fuel. If it smells like gas, then you have a bad injector (or two). If the cold start injector is leaking, all the plugs will be black. If the cold start injector is completely stuck open, the car won't run very long at all. It will dump so much fuel that you'll actually foul out the plugs and richen the mixture to the point where the car just dies completely. It won't start again until you clean the plugs and let the engine cool.

I also have had problems with screwed up oxygen sensors making the car run poorly. The Bentley manual shows how to test it. Check for bad engine grounds, bad cylinder head grounds, or bad computer wiring ground (grounds to cylinder head near #5 intake port). Also, pull off the vacuum line from the fuel pressure regulator. If there is any liquid in that line, your regulator is bad. Also, check to see that the line is still good---plugged in, no cracks, holes, etc. If it is unplugged or has any holes, the car will run rich (too much fuel pressure).

Let me know what you find...

James
james_535@yahoo.com

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