Once it heats up it acts like its missing without backfiring.

[nottione]

I just had a quick question for the forum. My 92' GT is having an issue that I am having a problem tracking down. It starts fine and runs pefect until it gets up to temperature. Once its at temp it acts as though it is missing or a couple of cylinders aren't getting fuel or fire, but there is no backfire. Because it only happens once it gets to temp I assume its not the fuel pump, injector or a vacuum leak because that would appear immediately. Any suggestions would be greatly appreciated. Thanks.

 

[2000xp8]

First thing, do a thorough check of the spark plug wires.

My next thought would be the TFI module on the distributer.
There is a reason that ford moved it on the 94/95 mustang, because the heat on the distributer is too much and they get ruined.

If it lands up being the TFI make sure to use a real ford replacement, everything aftermarket is garbage.

 

[jrichker]

The TFI module mounted on the distributor is usually the culprit for a high speed miss on a warm engine. If the problem does not occur when the engine is cold, the TFI module is definitely suspect. You may need a special socket to remove the TFI module, but most auto parts stores will have one for $5-$7.

Be sure to use plenty of the heat sink grease on the new TFI and clean the old grease off the distributor.

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