Hello again jag people. Can anyone steer me to the cause of my jag blowing black smoke when I rev the engine? Is there a component that regulates then mixture that I can replace? I just don't know where to start looking. There are so many dang vacuum sensor solenoid regulator valve switching controller thigamabobs on this engine. Any help steering me in the general direction would be highly appreciated. It's bad enough that a couple plugs keep fouling eventually. Thanks for any help. Bud

 

Quite a few possibilities: coolant temp sensor, fuel pressure regulator, enrichment switches, baro sensor in the ECU, oxygen sensors, leaky fuel injectors.....

Do you have a fuel pressure gauge and a volt-ohm meter?

Does this problem happen at all times or just under certain situations? Any running problems?

Is it always the same two plugs that foul?

Cheers
DD

 

As Doug said you will need some basic tools to diagnose and adjust your engine properly. You will need a DVOM(volt-ohm) meter, a timing light, fuel pressure gauge, compression tester and of course the requisite assortment of hand tools.

If the same spark plugs are fouling out you may have weak cylinders or leaky injectors.

The first thing you need to do is set the basics, throttle plates, timing and TPS. It wouldn't hurt to do a compression test while you have the plugs out.

 

I'll check these things first!