1994 Eddie Bauer Bronco - Extreme Heat

I'm the original owner of a '94 Bronco, 351 cid with 125,000 miles. It has a new cooling system - radiator, water pump, hoses, etc. (no leaks of water, oil or other fluids)

During the extreme heat ( 110 - 117 degrees in Las Vegas) the truck shuts down. It acts like what we used to call "vapor lock - boiling gas". The truck seems to starve for gas and air. It runs irradically [sp] when I do get it started after a short cool down to get it home.

It will drive fine most of the day until the heat gets extreme and this only happens in the summer months. (past three summers). The rest of the year every thing is fine with no trouble what so ever.

Any ideas would be helpful!

Oren

Reply to
noway
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Hi,

I live in Vegas too. I never buy gas from any station except Chevron especially during hot weather. Chevron doesn't put any corn in their fuel. Many of the other brands trade gas and you never know when you get gas with alcohol in it. While people will tell you that it is JUST FINE to run gas with alcohol in it, don't believe it.

Take a small amount of alcohol and the same amount of gas and put it in an open area and see which evaporates faster. Now imagine the fuel with alcohol in your fuel system on a hot day. As it circulates above your engine, it vaporizes. Give the good gas a try.

Reply to
Scott

Vapor lock is not a likely problem. Be sure you have a good fuel filter. If the fuel pump and regulator are keeping the pressure in specs, it won't vapor lock at the pressure modern EFI systems operate. You can buy a fuel pressure test guage from places like Pep Boys for about $40. It will work on most current EFI systems.

The first thing I would try is a new ignition control module. Yours should be mounted on the left fender apron near the rear. It is mounted in a heat sink which can cool it relatively quickly compared to the old location on the distributor. A bad module will not necessarily test bad. Any time it is running, it will likely test good. When you install the new one, be sure to use a good thermal paste or grease or, in years past, called heat sink grease to help it cool and greaty extend it's life. It is probably a fair idea to replace the grease every couple of years if you find yourself with nothing better to do some afternoon while waiting for the bars to open. Many electronics stores and computer shops have the stuff since it is used to attacth the cooling fan to the CPU in computers and other similar applications.

If the fuel pressure tests OK and you have replaced the ICM, your next step should be to get a complete diagnostic scan. Many independant shops have the equipment to do this but, the best equipment is, sorry to say, in the hands of a Ford dealer. That does not mean a particular tech will be able to correctly interpret the data or, that the fault will show up in any particular diagnostic session. Intermittent is the longest four letter word in the English language.

Good luck Lugnut

Reply to
lugnut

Under this heat any thing goes, trucks sitting idle (waiting for accidents to clear) have previously melted pavements.

Will check the system

I tend to burn things up when it comes to wires! Looks like I can handle that module.

Does this go under the heat sink and the ICM or just one or the other. The heat from the road under the fender is HOT. The other day the compass / temperature gauge stopped past 130 + sitting at an intersection.

Two things on my list now.

Thanks

Oren

Reply to
noway

After 3-4 years worth of rain in this fall, doesn't help if water night be in tanks at stations.

Thanks,

Oren

Reply to
noway

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