94 GT stumble/miss

GTVin

Member
Jan 15, 2019
52
4
18
San Diego
I have a stumble/miss once car warms up only at idle. Car has 50,000 miles always garaged and ford dealership maintenance. I cleaned MAF, changed PVC and replaced air filter everything else looks to be good and it's all ford motor craft. Any ideas or help is greatly appreciated
 
  • Sponsors (?)


Stumble or a miss would be less evident in the higher rpms, I would suggest to check for codes, better yet here is a link to a checklist that will help you with finding your problem: http://forums.stangnet.com/showthread.php?t=698148,
This shows you how to check for codes and perform tests on various sensors and other things that can cause idle problems.
 
I've had similar symptoms when my base engine timing was just a little too advanced. And when I used a (don't get me started) MSD coil and wires. When I put those in the trash everything improved significantly.

The checklist above is great of course.
 
  • Like
Reactions: 1 user
I've had similar symptoms when my base engine timing was just a little too advanced. And when I used a (don't get me started) MSD coil and wires. When I put those in the trash everything improved significantly.

The checklist above is great of course.
Timing was at 8° when the stumble was noticed. Timing is now at 12° it's a little more noticeable.
 
A cylinder balance test can help you pinpoint if your problem is limited to just one or two cylinders. After the KOEO test, stomp the gas-pedal and it'll kick into cylinder balance. It will flash out the problem cylinders. Could be mechanical, electrical, or fuel-related, but this can help pinpoint. It won't help if you have a more general problem (fuel pressure, tune, timing, vacuum leak, etc.).
 
  • Like
Reactions: 1 user
A cylinder balance test can help you pinpoint if your problem is limited to just one or two cylinders. After the KOEO test, stomp the gas-pedal and it'll kick into cylinder balance. It will flash out the problem cylinders. Could be mechanical, electrical, or fuel-related, but this can help pinpoint. It won't help if you have a more general problem (fuel pressure, tune, timing, vacuum leak, etc.).
Thank you I'll try this later