Still missing after DME relay, plugs, wires, Dist. cap & Rotor?

[Booney1golf]

I have an 87 911 3.2 that was running fine then I went about 3 months without driving it more than just starting it in the garage every 2 weeks or so.

I started it and it was missing some so I decided to change the wires, plugs, dist. cap and rotor & DME relay since I was not sure how long it had been. The car may run better but still has a slight miss when at idle or even when driving normally. The car seem to pull strong when I get on it but several people have heard the car and seem to think its a fire and not a fuel issue. The Fuel filter was also changed recently.

I thought about changing the coil but I hate to keep guessing due to all of the sensors, etc..

I'm trying to avoid just taking it to a shop but I might have to unless someone has something relatively inexpensive I can try.

Thanks for your time in reading my post!

Daniel Womack
1987 Porsche 911 Cab Wide-body
1998 BMW M Roadster
I love speed!!!

[DRACO A5OG]

Check the ohms on the ref/speed sensors.

[Flat6pac]

sounds like you have a non firing injector. They get that way from sitting, even a short time. Tap it, they will come alive.
Bruce

[kodioneill]

Possible that you may have a vacuum leak. Sometimes the brake booster hose get's brittle and cracks on the back of the engine. Acquire a vacuum gauge and check manifold vacuum at idle should be near 18 hg.

[Chuck.H]

Originally Posted by Flat6pac

sounds like you have a non firing injector. They get that way from sitting, even a short time. Tap it, they will come alive.
Bruce

To test this theory you can feel or listen (with a stethascope) to each injector - they make quite the clicking when they are functional.

Another test you can do is to get an infrared thermometer and look at each exhuast port to check temperatures - a non firing cylinder will be colder than the others... this is a good way to isolate bad injectors, spark plugs or plug wires.

Chuck.H
'89 TurboLookTarga, 342k miles

[T77911S]

drive it and then pull the plugs. also check for air leaks. check the intake bolts. injector Orings too. you may just have a smoke test done,

[Booney1golf]

Thanks to each of you. Some of these things I can do others are out of my knowledge scope. I will go forward with what I can and report back.

I appreciate the time spent reading and responding to my post!.

Daniel Womack
1987 Porsche 911 Cab Wide-body
1998 BMW M Roadster
I love speed!!!

[Jim Richards]

How old is the gas?

How's the O2 sensor?

[Quicksilver]

Sent a PM

[Booney1golf]

Thanks again for all of the help / responses. I put 1/2 tank of Super unleaded then added 12 onces of Lucas gas treatment and drove the heck out of the car once it warmed up.

The feeling of driving a Porsche that is running as it should: Priceless!!!

Thanks again to each of you through the years that have helped an average non mechanic be able to drive and own 4 different 911's!!!

Daniel Womack (Booney1golf)
1987 Porsche 911 Cab Wide-body
1998 BMW M Roadster
I love speed!!!