I have a on again/off again problem with my 3.0. From time to time the CEL comes on blinking. Today after blinking for a solid 10 minutes, it quits and the light never comes back on. I didn't think that was supposed to happen. The AC wasn't working too good until the light went off, then it blew cold.

It has a slight rough idle and pops every now and then when pulling away from a stoplight. Except for that, it runs smoothly. I've changed plugs and plug wires as they have about 105K on them. Twice when the CEL stayed on long enough I took it by my local Autozone. Both times it gives a "Cylinder 1 misfire". I've checked the coilpack by pulling the #1 plug wire out and it seems to be firing fine.

Any ideas?

 

On other forum areas on FTE I'm covered up with responses. Where is everybody?

 

This post is old, are you still having the problem or have you figured it out?

/matt

 

I've changed (or had changed) plugs, wires, coilpack, injectors; runs much worse than when we started all this. So no I haven't figured it out.

 

ok, if it's gotten worse since replacing parts, then most likely the parts installed were done wrong. i'm assuming this is for the taurus. Which 3.0 is in it, the OHV or the 24v? on 24v's they have a tendency to get massive vacuum leaks from the pcv system. and a large vacuum leak will most definitely cause running issues. If you can, get me the codes that are in the PCM and i can go from there.

Thanks!

 

I was getting a code stating cyl. 1 misfire. Plugs, wires, then coilpack didn't fix that like I thought it would. Next a shop replaced all the injectors and told me the reason it wasn't running any better was it needed catalytic converters replaced. It won't run at any speed without missing, but right now there are no codes. I do hear something that sounds like a vacuum leak, but can't locate it.

Shouldn't it throw a code if there is a vacuum leak?

 

yes, fords love to throw lean codes (p0171, p0174) for vacuum leaks.

I'm still unsure which 3.0 you have, if it's in the taurus. That year the taurus's had 2 different 3.0's, the Vulcan (OHV) and the Duratec (DOHC). has anyone checked compression on cylinder #1. A converter is not going to cause a miss on just 1 cylinder.

I've seen the vulcan motors break valve springs that cause a dead cylinder. It's not common, but i've seen it multiple times on several different vehicles (amazingly all in Taurus's)

 

It is the 3.0 OHV, whichever one that is. Regular not Flex Fuel. Most of this started when I put the new coilpack on. Its a Motorcraft coilpack I got from RockAuto. Could it have been bad? They (obviously) don't think its bad. But it went from giving a cylinder 1 misfire to just running bad without any codes.

 

ok, that's the vulcan motor. It's not unheard of to get a bad part out of the box. even with 99.9% good quality control, you're going to get a bad part once in a while from the factory. If you still have your old one, swap it back in, to see if it changes.

also, verify that the wires are correctly installed onto the coil pack and routed correctly. none of the wires should be twisted around each other. they need to be laid out somewhat apart from each other so as to not get crossfire. Wish I had the car here to test some things out!

now, for the wiring:
front of engine (when looking with the hood open)
<----------

cylinder identification:
rear bank:
1....2....3
front bank
4....5....6

coilpack:

1...2...3
5...6...4

make sure those are correct. after that is verified. get some carb cleaner, and spray around the intake manifold mating surface while the engine is running. you're looking for surges in the idle. also check where any and all vacuum sources come from the intake for with the carb cleaner.

oh, random thought.....

unplug the mass air flow sensor and see if it runs better. fords go into failure mode and run off of an air/fuel mixture table instead of being dynamic when there is no signal from the MAF.

and sorry for the slight delay, i work 14 hours a day with very limited interweb access!