missing hard around 2k please help no ideas on the cause.

[93 LX]

Background: Engine missing after driving for some time. At first it only happened once in a while but after a few days its now more consistant. The engine runs fine until the car has been parked for some time after the engine was warm.

Parts replaced: Cap, Rotor, TFI module.

Parts that have a problem: I noticed this evening when I had the dizzy out that the metal flag cup, the part that sits inder the roter had been rubbing the meag pickup assembly. There are or were little metal filings in the dizzy. I removed and cleaned the inside of the dizzy.

After reinstalling the dizzy I ran the engine for some time and not a single miss. When I took it to the store it start missing around 2k and seems to go away over the 3k range. Since I do not have a doner dizzy I am not sure what else to do.

Some possibilities are:

Replace plugs and wires tomorrow.
I went to the boneyard to get a dizzy but could not see the benifit to spend 50 bucks for a stock, used and no warrenty unit when one could be bought for 80 bucks with new electronics at a local parts. The problem with the new dizzy, part must be ordered.

Could the coil be bad and should I throw one at this beast? Any help or suggestions would be received with open arms.

Stumped,

Allen

 

[HISSIN50]

Allen, oh boy.
the problem i see is that since this is intermittant, you are gonna have to try to test stuff as it is malfunctioning. this can be quite a chore.

the PIP having interferance is not good. that would likely be where i would start, were it not for the exact dilemma you mention (cost/availability). you can get a new PIP and stick it in (gotta pull the dizzy and pull the shaft. some guys fight it all the way, others breeze through it). i likely would get a new/reman'd dizzy myself. but that is money, i know.

does it malfunction at idle ever? how often does it take a poo? i might have an idea or two if we know you can make it poop itself on demand or something close.

good luck Allen.

 

[trbkrb]

Seems like this problem is happening quite a bit recently. Mine started missing very intermittantly around 3,000 rpms, and progressively got worse, to the point it missed all the time, but ONLY when warm. Cold it ran fine. I used water flowing slowly from a hose to cool the distributor base when it was missing, and was able to make it stop until it heated up again. This was after replacing the wires, cap, rotor, and TFI (under warranty). I borrowed a distributor from a friend and swapped it out, and the car ran perfectly. Ended up the PIP was rubbing against the shaft like you mentioned, and it was not sending the right signals to fire the ignition. Apparently it has a crack in it that caused it to act up when hot. So I got a newer used distributor from another friend and it is running fine.

A friend that is a Ford tech said that he has seen the parts store distributors fail much more often than the Ford ones. He told me to only rebuild it with Ford parts if I go that route. The parts store rebuilts do not use the same quality parts as Ford, and it is very apparent when you look at them. When I get a chance to drop mine off to him, he will rebuild it for me, but the Ford parts cost around $100 or so. Luckily he will rebuild it for me for free.

But if that is all you can get, at least it should run for a few years.

Good luck!

 

[Danny-Boi]

I had a very similar problem with my GT. I replaced every sensor I could find changed the wires every thing. I eventually replaced my distributor...problem solved. I went with a MSD distributor.

Hope this helps.

Danny

 

[RS200]

I had the same problem on my '88 GT. I had changed the plugs wires, rotor and cap a few weeks back, but it was missing like crazy. I changed the wires and coil, with Accel 8.8mm wires that I had in the garage, and an MSD Blaster coil, same story. I hoped to prove that it was my new spark plugs causing the problem, but after the wires and coil, it ran like a dream.

 

[93 LX]

Update!

Ok I replace the wires, life time replacemtn on these so no money spent on that. Replaced plugs and found that # 7 was looking pretty bad. I thought I nailed it! Oh well got tricked on that. Shoud have known while working on the car on Holloween and all.

I decided to really heat this bad boy up. After a short cruise it started missing again. I took it home and held the RPMs to 3000 for 5 minutes. Man it really started missing, somuch so that I was able to hook a timing light to each plug wire and I could see the missing on every cylinder. I figure that its either the distribtor or coil but with a bad coil I figure it would just stop running all together.

Next stop, distribtor.

Allen

 

[HISSIN50]

good call. TFI, PIP and possibly (though less so in my mind) coil.

good luck.

 

[TrickStang37]

are you sure your plug wires arent grounding? when i had those cheap ass "lifetime" spark plug wires, with the lights off outside in the dark, you could see the spark jumping to anything metal really, like A/C bracket, intake manifold, valve cover, you name it. and this was with ALL the wires. my 9mm ford wires dont have that problem. maybe those "lifetime" warranty wires you got get too hot and the resistance is just too much when it could be easier for the spark to just jump through the insulation and ground out somewhere.

Tommy Boy put it best - "I can take a dump in a box and mark it guarranteed, I've got spare time .... my point is all you got was a guarranteed piece of ****!"

 

[trbkrb]

Sounds like it is missing more when hot now. Try cooling down the distributor with the engine running like I suggested. Mine stopped missing every time I did this, only to start missing again in a few minutes when it warmed up again. If it works, then you would know for sure it is the distributor.

If you still want the coil checked, you can use a volt/ohm meter to check it. Some of the auto parts places will also check them out for you. They can check the resistance to see if it is in specs. The speca are in my Chilton's book.