Hello I'm new to the list

Hello My name's Andrew I recently purchased a 1984 volvo 240 GL automatic
with 205000 miles on it. I'm glad too see this list is active. I also own a
1980 Oldmobile Cutlass Supreme Brougham and the list
alt.autos.gm.olds-cutlass sucks.

So far I've replaced the spark plugs, the spark plug wires, the distributor
rotor, and I've removed and cleaned the throtle body (Man, it was filthy)

Now I've got a question for you all.
When the engine is warm and in park the idle speed fluctuates slightly (Just
barely noticeable on the tachometer. When I put it in drive and put my foot
on the brake the idle speed starts to fluctuate more and more going higher
and lower each time until it dies. Or if I'm driving around and I stop at a
light the engine dies. I've found that if I'm about to stop and I put the
car in nuetral just before I come to a stop the engine will keep running. It
also seems to misfire at all speeds about once every 4 or 5 seconds. I
hooked up a timing light to all the spark plug wires and watched the strobe.
The flashing was constant on all 4 cylinders except for the fluctuating idle
speed i.e. it didn't go flash flash flash pause flash flash flash but it did
get slower and faster. This leads me to believe that it is not a spark
problem The worst part is it doesn't do it all the time. Just most of the
time. I'm currently taking a class in auto mechanics and the instructor said
it could be a leaking O ring on one of the injectors.
Any help to this problem would be greatly apreciated.
Also I've got the haynes book for my car and it seems there is no onboard
diagnostic system is this the case or am I just reading it wrong.

 

I'd be looking at the injectors and, how clean is your air filter?

All the best

Hammo

 

The air filter is clean I'll be checking the injectors in the next couple
days

 

Don¹t forget to check for air leaks as well...

All the best