Hi There,

In the middle of a vacation 2000mi away from home, our 1988 Econoline 250 5.0l motor home starts making problems. Have been at 3 workshops (with only French-speaking mechanics...) and all are clueless. Would be awesome if someone from here could help us!!!

Problem:

Car loses power after 30 min of driving at 50-60mph. Need to push it harder to keep speed up and then it starts stuttering in the highest gear when I push the gas pedal. Finally, it goes to 3rd gear to keep up the speed. I always shut it down then and let it cool. After 1h, it works again perfectly. This started to happen after we drove 1500mi with the car in the first week if our vacation without any problems. It first only appeared when we were climbing a hill (the first 1500mi have been flat roads). Now, the problem comes even after driving 30 min on a flat road.

Diagnosis/context:

- No pressure loss in cooling system and no loss of antifreeze (engine got new head gasket and thermostat 2000mi ago)
- No leaking water pump
- Fan clutch seems to work (not too much and not too little resistance)
- Temp gauge of the car unfortunately not working but testing showed that rad inlet hose has temperature of 175f, outlet hose is significantly cooler -- both directly measured after the problem occurred
- Car heater works as soon as engine is warm
- Engine and transmission oil levels are good
- Second garage replaced the fuel pump but that did not help
- Catalytic converter was tested and found to be good

My thoughts:

- From the test results above, all workshops say there is no issue with the cooling system. However I still think this is a temperature-related problem. After the car cools down, it works just fine again. Also, it seems to be really hot when the problem occurs, eg, the oil on the dipstick is fuming away. Maybe a broken pump and too little coolant going through the rad??
- Another trace could be the injection system. Over the last year, we had many issues with rust in the tank and fuel lines. Could the injector be stuck? However why would that occur for the first time when going up a hill?

I'm really clueless at the moment and the 3rd workshop does not seem to make big efforts to uncover the problem. Am stuck in a little town in northern Quebec and all other mechanics/workshops are booked and have no time.

Anyone has an idea what the issue could be or what I should check/do next? Help would be highly appreciated!!!

Thanks so much and sorry for the long post,
Sebastian

 

What kind of ignition module does your van use, I think its past the eecIV system, but the pickup's and modules are known for getting hot and shutting down. it would be nice to have a fuel pressure gauge with you when it acts up, that way you know for sure your fuel pressure is were it should be. I have seen fuel pump relays get hot and raise the resistance to the pump, which would slow it down, I.E. low fuel pressure., Only when Hot? resistance is playing a game with you., dont think engine is over heating, you would know that. think Ignition, or fuel. David7.3

 

Hi David7.3,

Awesome post. Thanks so much. Unfortunately, don't know which ignition module it is. Is there a way to diagnose whether the ignition works correctly? Will definitely do the test with the fuel pressure gauge. From what I read in the forum, the value should never drop below 30psi, right?

Cheers,
Sebastian

 

Rusty Fuel Tank and Lines? Sounds like the Fuel Filter is plugged up since the shutdowns are increasing and then runs ok after sitting for a while.

 

Very well could be, replace the fuel filter and cut the old one in half that will tell you the story. if its clean, rust is not the problem. see if the module is mounted to the distributor or it my be relocated in a heat sink near the radiator core or on the left fender well near the fire wall. David7.3

 

Oh yea, 30 psi is what you want to see at all times, 35 if under heavy acceleration. David7.3

 

My first thought would be the ignition module as well. It will work fine when cool, but when it starts to heat up the failure begins. It will usually get progressively worse as well. The fuel pressure test should eliminate that system as a point of failure. Good luck getting it figured out.

 

Sounds like the PCM /Igniton Module is retarding the timing....Do you have Duraspark II ? Or you have a plugged CAT....SO that means Your PCM could be baked or you have EGR Issues....or even a severe Vacuum leak....Where are you now ? I live in North Toronto .....I also speak French /Italian /German.....

 

Thanks so much for all your answers. It's crazy - the problem did not occur today when I had the van checked. Drove many KMs with a technician next to me and no prob. Timing was checked and is good. Maybe a power issue with fuel pump? Will check that and fuel pressure first if it occurs again. Thanks again and will keep you posted! Seb

 

Thanks man! Are currently in Quebec. Will definitely reach out if problem persists and we make it back home!

 

Hi Sebastian,

I say fuel starvation. Have the mechanic hook up a fuel pressure gauge and take it for a drive. My guess would be rust clogging the filter in the fuel tank and blocking fuel. When the engine is turned off, the pump suction stops and the debris falls away from the filter. The problem will be worse with less fuel in the tank. Keeping the tank full will help.
jim

 

That is Fabulous....If you need me, PM me and I will give you my phone #.....If I need to talk to a person that speaks Whatever......

 

i would replace the coil .when they go bad the heat really gets to them.i know its not related but my goldwing had the same symptoms as your van and it turned out to be the coil. good luck

 

Goldwing? we are talking trucks right?

 

He said:

Sometimes in the typical ignition system similar situations regardless on what they're installed have the same problems and/or fixes. I'm sure you already know this and that Richter was simply tossing out a possible fix related to his experience.

OTOH if someone is now making a Goldwing edition of a truck or van its news to me!