random engine issue -cuts out once warm

[funky technician]

I was just wondering about a problem i am tring to clear up with a new (to me) festiva i aquired, its an 89 FI auto, and it has less then 100 000k on it and it burns no oil, and seems to run alright cold, but once it warms up, it starts to miss while your driving, like as if it were running out of gas, like it will sorta quit for a second and then pick back up and be fine for another little bit, then it does it again, i was suspecting the distributor, its a vacumn advance disty., and i have another one to swap out to check, but i was just wondering if anyone else has any ideas to help out with the trouble shooting, i have checked the plugs already, they seem fine, new gas, oil changed, the coil was replaced apearently by the previous owner, but that doesn't mean anything, it was a used coil he put in.

[Pu241]

Check the coil, you can do that with a multimeter and the specs in the manual.
If that not it I'd check the distributor module and then the ignitor module.

http://www.fordfestiva.com/forums/showthread.php?t=22235

[WmWatt]

A failing ignition module (aka transistorized points, the black plastic thing inside the top of the distributor) can cause intermittent problems when warm. You can remove it and take it to some auto parts stores who will test it for free. More information is available at

https://www.ag384bn.bravehost.com/Cars.htm

[JohnGunn]

When I hear that an engine is missing I automatically want to replace the plugs before doing anything else. You said you checked them. How did you do that? Do you know when they were last replaced?

That the problem does not show itself while the engine is warming up and, therefore, running richer, does suggest that the plugs are not the problem. I would think plugs which do not miss when running rich would do at least as well when the engine is warm and running leaner.

Nonetheless, I would probably replace them, just to clear my mind of them.

John Gunn
Coronado, CA

[funky technician]

plugs are new, and show signs of a rich mixture after 1 hour of driving

[kartracer46]

Check and clean the connection on the VAF. Also make sure to pull the intake ducting off and check for excessive oil and dust. A good cleaning will remedy this issue most of the time. A little oil and dirt in the throttle body will make it act oddly. If it has been setting for a bit, I usually do this as a first step along with plugs, cap and rotor.

Keep us posted!

[WmWatt]

When my Festiva is missing I wipe the ignition wires and distributor cap with a clean rag. That usually clear is up. It's easy to confirm missing with a vaccum guage. The needle vibrates.

[funky technician]

ok, so some more info on the quitting issue, the car ran fine for like about 2000 kelometers, i started to get confident that the problem "fixed itself" (which never happens in real life) then out of no where, while on a road trip, the car started studering, and then it just quit all together, .....on the side of the road....... i cranked it over and over again, i'm pritty sure i could smell gas while tring to start it too so i'm sure theres not a fuel issue. then out of no where again, after about 10 minutes, it started, ran rough for about 30 seconds, then cleared up and has been fine ever since, but i obveously don't trust this now, so i ordered a new distributor and coil off e-bay, replacing them out of spec because this problem is so intermitenant that its making troubleshooting it difficult, i noticed someone on hear mentioned the "ingnition module" and something about that black thing on the distributor, my car has a vacuum advance distributor and therefor has no black thing, just a vacuum bellow with 2 vacuum lines commin off it, and the EMF noise eater (small black thing on distributor), but i dont think that noise eater does anything but absorb EMF noise to keep the buzzing out of your radio . is there another ignition component I'm missing? it there a "ignition module" somewere on the car that's failing possible, if so i'm unawair of this component. so anyhow, any advice would help at this point, and to re-idderate, the car is an 89LX fuel injected auto

[m715]

The ignition module IS the "black thing", and is located under the cap that can be removed after you pull off the rotor button. Ignition modules *can* do what you describe when hot, but my experience has been they just fail.
One thing to keep in mind.... your distributor in the 1989 ATX application has different spark advance weighting to give it a little extra zip because it is an automatic transmission. None of the auto parts suppliers out there show a different distributor for the ATX, but what I am telling you is true. I use them on my carb cars with MTX to give them the extra spark advance. IT MAKES A DIFFERENCE!!!! Don't let that distributor get away as a core! You may find that you need it. If the module is indeed bad, you can swap it to your original distributor.
Make sure that you do not have a pressurized crankcase (blowby from worn rings) pushing oil through the distributor into the area where the module is. This happens!

Michael

[m715]

Two more pictures

HTH
Michael

[funky technician]

hay thanks, i was thinking too, can i make the new one into the better one instead of the other way around, because mine is kinda weather hardened and this one is gonna be new, cit would be nice to use the new one if it can be modified

[LittleHoe]

Crank Position Sensor possibly? My dads just died and through an 02 code which is the crank sensor. He said it has been stalling at random and then finally just today while trying to diagnose the unkown problem it died and threw the code.

Only problem is the crank sensor is in the distributor I believe so he needs to get another dizzy... $160 from the parts store there so I am going to ship him a used one from one of my parts cars here I think...

[JohnGunn]

The ignition module IS the "black thing", and is located under the cap that can be removed after you pull off the rotor button. Ignition modules *can* do what you describe when hot, but my experience has been they just fail.
One thing to keep in mind.... your distributor in the 1989 ATX application has different spark advance weighting to give it a little extra zip because it is an automatic transmission. None of the auto parts suppliers out there show a different distributor for the ATX, but what I am telling you is true. I use them on my carb cars with MTX to give them the extra spark advance. IT MAKES A DIFFERENCE!!!! Don't let that distributor get away as a core! You may find that you need it. If the module is indeed bad, you can swap it to your original distributor.
Make sure that you do not have a pressurized crankcase (blowby from worn rings) pushing oil through the distributor into the area where the module is. This happens!

Michael

Hi, Michael.

This is a great post with important information that is not commonly known. Thanks.

From your four pictures it looks as if the pictures get out of focus the closer your camera is to the subject. I have the same problem with my Canon A630 unless I use the Macro Mode of the camera. See if you can't find that function on your camera. Here are two pictures of an Ignition Module taken with my camera from the same distance, without and with macro mode enabled.

[m715]

No Macro function on my cheap Kodak It sure would make a difference, wouldn't it!
You show a good example of the 1990 up module for reference also. This was the application used for all our cars after the 1989 year ONLY fuel injection system, which used a different distributor and coil also!

HTH
Michael

[funky technician]

Hi, Michael.

This is a great post with important information that is not commonly known. Thanks.

From your four pictures it looks as if the pictures get out of focus the closer your camera is to the subject. I have the same problem with my Canon A630 unless I use the Macro Mode of the camera. See if you can't find that function on your camera. Here are two pictures of an Ignition Module taken with my camera from the same distance, without and with macro mode enabled.

ya my 93 has that plug on the distributor, but my 89 only has the vacuum lines and a few smaller plugs.