Mechanics

MISFIRE

1985 Ford Crown Victoria

Engine Performance problem
1985 Ford Crown Victoria V8 Two Wheel Drive Automatic 88900 miles

all right, I have an 85 crown vic 5.0 with the TFI IV universal distributor. I have a misfire on cylinder 2 and 3. Ive replaced plugs, wires, cap, rotor, hall effect unit, module, coil, timing dead on 10 BTDC, all the fusible links have been checked, voltage regulator, throttle position sensor, and solenoid new. I know for a fact that its just not getting good spark out of the distributor on those two cylinders. Motors been rebuilt so its nothing mechanical
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BILLY_BOB2003
March 30, 2009.



Engine misfiring can be caused by worn or fouled spark plugs, a weak spark (weak coil, bad spark plug wire), loss of compression, vacuum leaks, anything that causes an unusually lean fuel mixture (lean misfire), an EGR valve that is stuck open, dirty fuel injectors, low fuel pressure, or even bad fuel.

Rasmataz
Mar 30, 2009.
I know all that, my question is why is it misfiring if all of those are good. On the scope those two paticular cylinders arnt getting primary switching to the coil. So why is that

Tiny
BILLY_BOB2003
Apr 11, 2009.
You have not done what I suggested therefore since you know all of that you should be able to figure it out. Sorry! I'm not a magicman

Rasmataz
Apr 11, 2009.
I said what ive done and you either told me to check what I had already replaced or checked. You also clearly didnt read what I said about the scope reading low spark output from the specific two cylinders meaning theres a problem with the ignition sytem DAAA. For what ever reason the pcm is telling the ignition moduel threw the spout wire to not switch on those two cylinders. This means that theres is a short to ground somewheres between the spout wire and the pip wire, or the pcm is fried. It turned out to be the pcm. If yall really new what yall were doing like us real mechanics then you would be able to figure it out

Tiny
Billy_bob2004
Apr 23, 2010.
Our technicians are real mechanics that are in here trying to help people. We do our best to provide good advice to find the probable causes and recommend a sound repair plan. We are sorry we were not able to help you figure it out your problem. We are glad to hear you were able to fix your car.

2CarPros Mike
Apr 23, 2010.