Melting in the Desert


I have a 1989 Ford E-150 Econoline Cargo Van with a 6-cylinder 4.9 EFI engine and an automatic tranny.

The van runs great in cold weather but as soon as it starts getting hot (like now) it will run about 20 minutes and then shut down…as if it is vapor locking. I have to let it sit for 20 minutes to an hour - depending on how hot it is outside before I can get it runnung again. I am broke-down on the Interstate and a 30 minute drive can easily take me 2 or 3 hours, not to mention I am sweating like crazy in the heat.

I have replace the electronic fuel pump, fuel filter, EGR Valve, EGR Sensor, O2 Sensor…

Please…please help with any ideas!




Sounds like a classic case of the engine electronics giving up the ghost when hot. I believe it is called the TFI-IV module.


Yes, the ignition module, on Fords, is notorious for stalls and failure to start…especially, when hot. Try another TFI-IV ignition module.


I second the TFI-IV ignition module. This kind of explains it.

If you replace the module you MUST use the special electrolytic grease that comes with the new module or the new module will fail pretty quickly.


A huge thank you to NYBo, hellokit, and ok4450. I purchased an ignition control module today for less than $40 and installing it this evening when it cools off here. I am simply amazed… I had the Ford Dealership work on this van last summer and after spending almost $500 they said they could not isolate the problem. The ignition control module was never discussed by them. I can’t believe how many times I have sat on the side of the highway broke down, waiting for the van to cool off so it would restart. A $40 fix…(laughing insanely!!!) Thank you all so much. I appreciate your courtesy and professionalism helping me to identify the problem! Peace and joy to all!!


hey tanker:

curious. what type? kc10 extender, or m1a1?


That would be the M1A2…when I retired my tanker boots in 2001!


thanks for serving.

i appreciate it.

and i hope you dont get recalled.


Hope that module fixes you up. It’s amazing that a Ford dealer of all people on earth did not consider this as their first suspect.
Many people have sat on the side of the road, especially during hot weather, due to those modules (including me a time or two). A few unlucky people were actually killed and injured when those modules failed at a bad time; as in crossing an intersection.

(Just a note. There is a tester that can be used for inspecting these modules but it is not a reliable test. The modules fail due to heat and short of a catastrophic module failure, the module will cool slightly by the time the test is performed and the tester will show the module is good. If you want to know just how hot those modules get, turn the key on for a few minutes with the module removed and plugged into the wire harness. The metal plate on the back will become scalding hot quickly and you could fry a hummingbird egg on it. When you change the module, you will need a special little tool, or a 4 MM nutdriver/deep socket or a 7/32 nutdriver/deep socket. Try to avoid rotating the distributor if possible.)

And agreed; always a tip of the hat to past and present uniformed personnel. :slight_smile:


Ohhhh myyyyyyy…

Replaced the Ignition control module, new spark plugs, wires, distributor cap & rotor, and PVC valve. Got on the road and after about 15 minutes down the highway the oil pressure gage dropped to zero (I HAVE TRIPLE CHECKED THE OIL AND IT IS FILLED TO THE APPROPRIATE LEVEL) and a few minutes later the check engine light came on…5 minutes after the check engine light came on it started hesitating…doing its slow roll and die dance on the highway. I had a friend follow me this time, so fortunately I was not stranded. Yup, the van sits well off the highway in time-out since it will not run.

Oil sending unit? I am close to my wits end. Please, I will entertain any and all ideas. And I do thank those who have contributed thus far and also the kind comments cappy and ok4450, it has been my pleaseure to serve.

Peace all