injector timing ---'94 4.6 T-Bird

I suspect my injectors are on all the time. MAF and TCP appear to be okay. Getting suspicous of the PCM. Don't have means to measure injector intervals. Any thoughts/suggestions?

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Farley @nonymous opined in

Warning, I'm not famiar with the 4.6, per se.
Go to a parts store and get a "NOID"... shows when injector fires.
WHY do you suspect them on all the time?
sidetrack:
I'm an IT customer support engineer, vocationally, though I dont do that now..
One of the biggest frustrations is when a client asks.. "How do I install a framistan fixer?"
Then we have to go thru the ballet of determining the symptoms or failure that he's trying to correct.
/sidetrack
Does the engine start when you floor the accelerator?
If the problem is apparent flooding, the Engine Coolant Temp sensor could be bad or the Fuel Pressure regulator could be bad.
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Backyard Mechanic wrote:

Never heard of a NOID before. Searched Google. Price okay by me.

Lots of smoke. VERY HEAVY fuel smell at tail pipes.

Yes. Engine runs fairly smooth at idle and hi-rpm, cold or hot.

ECT has resistance (not open). Can induce subtle operational changes by
pulling off fuel pressure regulator vacuum hose. Not a valid test but
shows its doing something.
Background: Problem showed up at time of or after fix of spark plug misfire (with diagnostic code). Two plug wires were shorting. Did not replace plug wiring. Taped up for temporary fix (wires are 14 months old). Cleared code, no code reported since. OBD-II scanner shows timing at 20 deg. BTDC (should be 10). I suspected a timing chain jump (previous post) but a couple of respondents suggested NOT.
I'm kinda lost. All I know is if I start it one more time I'll have the EPA citing me.
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Okay... I wonder if it starts BETTER when you floor it, or is very difficult to start if you DONT touch the pedal.
I doubt the injectors are on ALL the time - and a timing problem would not result in an obvious rich condition.
I would GUESS that it may be the pressure reg. You might have the Fuel Presure checked.
The ECT remain a possibility, though.
Farley @nonymous opined in

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says...

All that should be done, but did you get the engine temperature when you had it scanned? I've not seen it as much of an issue with Ford's, but if this were a Chevy the first thing I'd check was the water temp sensor. I'm not sure how your's works, but on a Chevy if the circuit gets corroded at the connector, it will read a very high resistance, making the vehicle think it's 40 below outside and will turn up the juices to compensate. Neat thing is the computer won't set a code, it's doing what it's supposed to do. Next time you hook it up, make sure the computer is seeing a temp in the ballpark. I'm not sure about the T-bird, but the gauge usually uses a separate sender than the computer. I'm leaning toward fuel pressure, though.
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John Alt wrote:

John, B.M.
Thanks for the replies. You both are pointing at the same things. Gives me something to look at tomorrow. Your suggestions had me do some more investigative poking around on the 'net. Learning a lot about all this EEC stuff. Makes me kinda miss my 283 on my five-seven chevvy. It was so simple even I could understand it.
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I'll unlurk and suggest looking for a loose or cracked vacuum line - I don't remember on the '94 for sure but I think there is a MAP/BARO sensor that measures air pressure and manifold vacuum - if the hose is off or leaking black smoke goes everywhere - if the car will run at all... Just look closely where the damage was repaired.
Mine was on the fender - had a mid-size vacuum line - but the 'Bird was a few years older with a 5.0L, I think your's has EEC-IV like my 'Bird did...
Paul in Dayton

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Fuel pressure possibly too high. Put gauge on it and check. Basics, is the air filter plugged?

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