Electrical or computer problem?

[stgninja]

Have a new problem with my '95, 3.1, APV.

On my way to work Fri. a.m. about a mile away, the engine speed and power began to drop. After trying to accelerate the engine appeared to maintain the then current level of power but began decreasing in power with or with out more gas. The engine died as I coasted to the next 4-way stop never to restart again. The tank is full and the fuel pump, filter and screen were replaced 6 mo. ago. The engine is turning over and is getting fuel. There is no ignition of fuel. After scanning for trouble codes all I got were codes that I had neglected to clear after other repairs (33, 34, 45). I get 33 & 34 when running while working with the air cleaner off and I just replaced the O2 sensor (45).

When I replaced the Ignition Control Mod. NAPA did not have a distributor with a p/u coil pressed in so I got the ICM and reinstalled my distributor. Is this problem most likely the p/u coil and for a reman'd distributor I need to find a different supplier (get a great discount from my NAPA guys)? Is it possible this is an ECM problem. I think I have replaced everything else in the electrical system in the last 6-12 months...plugs, wires, ign. coil, ICM, starter, alternator, cap, rotor, o-ring, been timed (thanks Rich, did have to install my own spades).

As always any help is greatly appreciated. One thing about this vehicle, it runs great after everytime I work on it. Then when something goes wrong it usually kills it like this and I have to drive the fun car. 82 RX7, fun to drive but doesn't haul many tools and is not so easy for a 6'3" tall man to get in and out of .

stgninja

[jeffcoslacker]

Hold the coil wire about 1/4" from the motor and have someone turn the ignition on then off again, see if there's one arc as the ignition is shut off. If so, it probably is that pickup. You can also check it's pulse at the coil, one wire is hot, one ground and one pulse. If the signal wire doesn't pulse, check the continuity of the pickup. If you read infinite, it's shot for sure. It should read high/low/high/low as the engine is cranked.

If you have a good pickup signal, the ECM may be a factor...

[stgninja]

I got a reman'd distributor with a lifetime warranty and the apv runs again. It does seem to be running a tad rough and is hesitant with an occasional backfire upon acceleration. I started it right up and after reaching operating temp I timed it and took back the core. was running rough on this trip.

Any ideas?

[jeffcoslacker]

Originally Posted by stgninja

I got a reman'd distributor with a lifetime warranty and the apv runs again. It does seem to be running a tad rough and is hesitant with an occasional backfire upon acceleration. I started it right up and after reaching operating temp I timed it and took back the core. was running rough on this trip.

Any ideas?

Make sure you aren't swapping spark somewhere. Make sure the rotor isn't holed, no cracks in the cap, watch it run in the dark and look and listen for crossfiring in plug wires, or a coil shorting to it's mount. I've seen a few of those type II HEI's blow spark out of the coil core.

[richtazz]

acceptable resistance in the pick-up coil is 500-1500 ohms. Any less, you have a broken winding or one of the wires is internally broken. Any more and the windings are starting to short out. Reman distributors are common to have badk pick-up coils right out of the box. When testing, make sure to wiggle the wires, if the resistance starts jumping all over, the wires are frayed inside the insulation and causing you occasional mis-fire/backfire/no-start.

[stgninja]

The cap and rotor are new within the last six mo. Will try resistance check.

Thanks

[TestingTesting123]

I had the exact same problem w/ my '95 Lumina 3.1L... Stalling.. Power loss.... Turned out to be a loose connection on the computer module.. Could be ???

[stgninja]

My resistance at the p/u coil is 861 and only fluctuates 1 or 2 ohms when the wires are moved. So I guess I can rule that one out. 861 is certainly between 500 and 1500 ohms.

[richtazz]

yep, dead in the middle. As I stated in my answer to your PM (posting here for anyone else following this thread), I'd check to be sure the distributor is installed properly. One tooth off will make a big difference (15 degrees of timing), and cause the loss of power issues you describe.