Running rich (smell rich)
 

Hi all fellow Pelicans, SmileWavy

My Porsche 928 S2 from 1985, is running pretty stable in IDLE and in general seems to run also fine when driving around.
But there’s a smell behind the car (coming from the exhaust) that it seems to be running rich. And if a friend is driving behind me in his car, he’ll typical when we stop and talk say “your car smell like an environmental hazard”. :-/
So it seems the problem is there also not only running in IDLE.

Does any one know of a “checklist” of stuff to walkthrough for finding root cause of such a problem?

I did already change spark plugs, ignition caps/rotors, air filter, engine oil, water pump, timing belt, coolant.

Thx in advance.

BR
Chris

Maybe some things to check would be the MAF, O2 sensor, Maybe the Ignition module. They make a special cleaner for the MAF.

Hi,

Thx for the answer harborman, I appreciate it.

I’ve tried cleaning the MAF with break cleaner, I wasn’t aware there was a special clear? Where do I get that?
Regarding the Ignition module, I haven’t looked at that actually, what do you recommend I do to investigate that?
O2 sensor, I don’t think mine car have a O2 sensor, I’ve looked at the x-cross section of the exhaust and there’s no O2 sensor to see. Unless I look the wrong place?

Yes, there is a special MAF cleaner. Most auto stores have it. It should have the o2 sensor, maybe hard to find. Do a search here on Pelican. Not sure of the condition of your car, but it might need a complete gone through, like grounds, fuse panel, connectors ignition wires, timing, etc.. But check the simple things first.

Harborman,
S2s don't typically have O2 sensors. None of my 3 have them. Definitely agree with the checking the simple things first.

Many O2 sensors listed for the 928. But maybe the S2 is different. I have the 86 928S and it shows an O2 listed for my motor. It is a key component in checking air/fuel ratio.

The S2 IS different. I've never heard of an S2 with an O2 sensor, but of course I could be wrong. I've just never heard of one or seen one with an O2 sensor

Does your car have the cat on it? Has it been gutted, maybe by a PO?

My 82 stinks to high heaven, but she has no cat.....

Hi again,

Sry for a few days silence on my side. Been alittle unexpectedly busy.

Mine for sure dont have cat anymore, I replaced it with x-pipe instead. There was no O2 sensor. And the car was running rich beforeI did this exhaust change, so shouldn’t be the reason of the “running rich” problems.

Maybe the O2 sensor came in 1986, if your car, Harborman, has an O2 sensor?

They list an O2 sensor for the 1986 928S.