Car stalling when gears are put into park

[isorensen]

I recently had a mechanic do a tune up at my home and now my car is running worse than before. The plugs were changed, the air filter was changed and the fuel filter was changed an I changed the map sensor. Now I start the car I get a smell of fuel as if the car was flooding with fuel and after I drive my car for awhile my car will stall when I change gears from drive to park. Any ideas on how to fix this problem. My car is a 1992 VP Executive Commodore Auto.

[Brett_jjj]

It could be a faulty fuel pressure regulator,when these wear out they can leak fuel past the fuel pressure regulator diaphram into the inlet manifold causing it to run crook.Its a fairly common problem on the older V6's..it might also explain why its getting a strong smell of fuel too..Also why was the MAP sensor changed,Id retry the MAP sensor you removed and see if it happens then...

[isorensen]

Thanks for your reply. I will look at your suggestions in the morning and change back to the original map sensor. I still think that the mechanic that done the service has tampered with the cars computer as I had ver little trouble with the cars performance before he done anything to my car. Again, many thanks for your reply.

[Krisp]

he cant tamper with the cars ecu

[isorensen]

Why is then that these problems now seem to be happening after this mechanic stuffed around with the cars computer and I got the distinct impression that this mechanic had no idea what he was doing while he was doing whatever to the cars computer.

[isorensen]

It could be a faulty fuel pressure regulator,when these wear out they can leak fuel past the fuel pressure regulator diaphram into the inlet manifold causing it to run crook.Its a fairly common problem on the older V6's..it might also explain why its getting a strong smell of fuel too..Also why was the MAP sensor changed,Id retry the MAP sensor you removed and see if it happens then...

Here is the latest. My neighbour is mechaniclly minded and he had taken out the spark plugs and the gap in all the plugs were 3mm so he changed the gap to 1.5mm which is recommended by GMH. Now the car is starting without any problems with no smell of fuel or flooding. But the problem now seems to be after I took the car for a drive for about 15mins and got back home, the car stalled again when I put it into park. Also after the car sat for about 2 hours the car was difficult to start but there was no smell of fuel or flooding but it was running rough and the idle seemed to be a bit low and again the car stalled when I changed the gear to the park position. Any ideas what this new problem maybe and how to fix it.

[wortus]

Have you checked the spark plug leads for both an open circuit and not exceedign max. recommended resistance?
Also have a look at the purge cannister components there may be a fault letting vapour into the inlet manifold all the time (it's only meant to purge when the motor is warmed up and the car being driven above a certain speed).
New plugs come pre gapped at 1.5mm seems strange they were at 3mm!

[isorensen]

It could be a faulty fuel pressure regulator,when these wear out they can leak fuel past the fuel pressure regulator diaphram into the inlet manifold causing it to run crook.Its a fairly common problem on the older V6's..it might also explain why its getting a strong smell of fuel too..Also why was the MAP sensor changed,Id retry the MAP sensor you removed and see if it happens then...

Today I finally got around to replacing the fuel pressure regulator and changing this part has fixed the problem. Many thanks for all your help.
Regards,
Ian Sorensen