84 Regal T-Type Too Rich--Any Ideas?

[Art Turner]

Hello all,

New to the forum, long time Regal owner. Bought the 1984 T-Type in 1984. Sold it to a friend when we moved out of the US in 1998. Bought it back from the friend this week.

Here's the problem:

It stumbles/hesitates/flashes service engine soon and blows black smoke under moderate load or moderate acceleration. I assume that the black smoke means too much fuel.

It's running 40lb injectors with a matching chip.

I replaced the air filter and several vacuum hoses.

There are no trouble codes stored.

I wish I could give you Turbolink data, but apparently the interface box is fried--it won't communicate with ECM.

Any pointers on next steps would be appreciated.

Thanks!

Art

[Keller]

Is the Check Engine light blinking or fluttering quickly?

Can you check resistance across poles of individual coils? These values may reveal a problem.

[Art Turner]

Originally Posted by Keller

Is the Check Engine light blinking or fluttering quickly?

It's flickering randomly, only when the engine is stumbling/cutting out.

Originally Posted by Keller

Can you check resistance across poles of individual coils? These values may reveal a problem.

I can check those in the morning and post back.

Thanks!
Art

[Art Turner]

Resistance across pairs (1/4, 2/5, 3/6) is around 10,400 ohms. It's an 87 coil with proper adapter to convert.

Thx

[Keller]

Resistance seems a little low. But I doubt that is the origin of the issues.

The fact that it cuts out in this way might indicate an intermittent wiring connection. The question is what wiring is at issue. Since you are getting the light, it may indicate the engine is momentarily stopping. It could also indicate an intermittent signal from a sensor such as the crank sensor, cam sensor, etc.

[Art Turner]

I was starting to think the same thing...went for a drive in field test mode. The check engine light indicated closed loop (in fact it started in closed loop).

The car would drive normally indicating closed loop. Then it would miss/stumble/cut out and the check engine light would flash erratically at the same time. Then it would smooth out and indicate closed loop. Check engine light never indicated rich exhaust.

The PCV valve seems a little loose, and I've had the most trouble with the vacuum line going to PCV, but that seems like that would be more a problem at idle.

Art