Car has been sitting for few years . 100,000 miles .Just finished plugs wires, cap, rotor some clean fuel. Spark seems weak out of both coils . Runs on either unplugged . . However runs with some black smoke. Smells of fuel . Clears a little when warmed up . Doesn't run well enough to drive .

 

Many possibilities.

A few quick ideas:

- Coolant temp sensor for the fuel injection is skewed "cold"....so the ECU commands extra fuel even after engine is warmed up.

- Fuel pressure regulator is faulty...either allowing excessive pressure or having a leaky diaphragm which mean raw fuel is drawn directly into the intake system

- Vacuum line to ECU is broken/disconnected

- Injectors leaking raw fuel into the cylinders and/or sticking partially open

Each of the above can be discussed. Post back !

Cheers
DD

 

Thanks for the check list. Does the vacuum for the ecm come off the right manifold. It does have the original fuel injector harness.

 

No. It comes off the balance tube at the rear of the engine.



Which might be a problem. Intense heat = cracked insulation = grounded wires = injectors staying "on"

Cheers
DD

 

Ahh! The vacuum off the middle of the vacuum tube was chewed by a rodent. I just cap it off for the moment. That is getting repaired next. I was looking to buy a fuel harness for Xmas.

 

You don't wanna have a go at making your own? Not all that hard and you'll save a ton of money.

Cheers
DD

 

capping that off won't alleviate your problem, as this IS the problem: when that line is open, the ECU sees a wide open throttle condition, and will severely over fuel the engine. You will likely foul the plugs to the point of killing the engine and not being able to restart (until you change the plugs, that is).

-M

 

Fixed the vacuum line . What a difference. No puffing noise out if the exhaust. Still plan on replacing. harness ,seals and refresh injectors. First drive. Trans mount banging and alignment way off.

 

Thank you Doug and Mike for your knowledge and thoughts.