need some help here!
 

Ok, I took yesterday off so I could install the engine (which didn't happen) so I'm stuck at work today. Litterally SUCK at work! It's 95 degrees out and our truck won't start. The truck is a 95 S-10 Blazer with a 4.3 6. The past couple of weeks it's been doing this. The truck will be running well, but when you stut it off, it won't restart. It only happens when it's hot out. Earlier in the year when this happened, the dealer said the fuel pump was bad and hit us for $1200 to replace it. Low and behold the receipt says NO WARANTEE on it! What I can determine is that the fuel pump is NOT running when the ingition turned on. In the past when the truck cooled off the pump would turn on and the truck would start normally. Where we parked though is in the direct sun so it's no cooling off enough. Because the issue seemed to be a heat related fuel pump issue, I tried replacing the fuel pump relay. It seemed to make sense as the relay is directly above the engine in the engine bay. Well, apparantly the relay wasn't defective. That or I replaced the wrong one. Dealer said it was the middle one of the three. Does anybody have any ideas? Is is possible to have a vapor lock situation that would cause the fuel pump to NOT run?

Cord, I can't help you with the engine. I'm as baffled as you.
But, I thought I would move this back to the top for you.

Good Luck

I also don't have a clue Tim. Sorry.

No help today but if your pretty sure its temperature related, go to radio shack or some electronic place and get a spay can of freon or whatever they are using as a cooling spray now and start spraying things, relay, pump, etc. Ive found more than 1 problem with that stuff.

Are you sure that the pump is not running? It should only run for a few seconds when you first turn the key to the on position then shut off. Listen when you start it cold, turn the key to the on position, the pump will pressurize the system, and shut off. Next time it is hot do the same and listen for the pump. If you still hear the pump pressurize the system you need to look else where.

Ignition coils do funny things with heat. I just tuned up my buddies 93 4runner because it had a miss when it got up to temp, it was still there when we were done. I recommended he replace the coil because of mileage and age adding if it was mine that is where I would start. He took it to the shop I use to manage, $800 later (mostly diagnostic time) he had a new coil. Truck runs great, he wishes he listened.

What kind of dealer will not warranty their work.

John

Well, after the sun dropped behind a building the truck cooled off enough to start. The Mrs. just had to get some stuff from her work so we drove over there. I was idling in the parking lot and the truck quit. The temps were around 240. Hot, but it was 100 out. Naturally the truck wouldn't start. I dumped alot of water on the engine and pulled most of the heat out of it. No luck. I pushed the truck into some shade and left the hood up. After a hour or so, it started up normally. Naturally we headed straight home. And it wouldn't restart when we got in the drive way.

Pump is definetly not running. I'm listening for it before I crank. If I hear the pump I know that it'll start. No pump sound no start. The question is why the pump isn't running. Where does it get it's signal to turn on?

When you turn the key on it gets power, of course, but an internal presure switch will make it start pumping. some how, it's either holding presure in the line and not letting the the pump start. Or it's not getting power.

Cord could it be a crank position sensor or something like that? I know that on one can and I can not remember what one it was that I worked on a while back the fuel pump would not turn on because the crank position sensor was bad. Or there is perhaps a wire problem ie bad ground or bad plug in the harnes. I would get a wire diagram if you can fallow them and start to trace the problem one wire at a time. I wired in my own relay into my Ford and never had another problem. Well that is not entirely true. The relays that I could get were not high enough amperage and they would occasionally (about every year or so) burn up with out warning. So I just kept a extra in the truck and put it in there. I would jump the Fuel pump relay and see if that will get her to start.

Tim, what you are experiencing is almost exactly what my wife experienced when she had her 93 Chevy Astro MiniVan with the same 4.3v6.

It would run, then die, run for days then nothing, etc....finally took it into the dealer and it was a bad fuel pump :mad: . I tried to get it covered under warranty but they declined. They needed to pull the tank on the van in order to change it.

1200 for yours :eek: :eek: :eek: mine was 450.00 up in the UP of Michigan as I was up ATV'n the weekend it completely died.

As fas as your replacement pump having a warranty, I would think most aftermarket items carry a ONE year warranty.

Jeff