'95 Caravan Fuel Pump or Relay Issue ?

UPDATE: Found the fuel pump relay. As it had the same numbers as the rest of them, I swapped it for the one next to it. No change. The van started right up this morning, and ran for about 30 minutes. Then, it just died, instantly, as if someone pulled the coil wire....

Could this possibly be the crank sensor in the distributor doing this?

Thanks Rick

By saying it shuts off like someone pulled the coil wire should tell you that it is not fuel related!! A fuel pump/pressure problem will not just shut down like pulling a wire, it will slowly start to run rough, maybe some spittering and sputtering and then cut off. Have you checked for fault codes? A crank sensor would be more likely then a fuel pump issue

Glenn Beasley Chrysler Tech

i agree crank sensor or maf sensor..good luck.

By saying it shuts off like someone pulled the coil wire should tell you that it is not fuel related!! A fuel pump/pressure problem will not just shut down like pulling a wire, it will slowly start to run rough, maybe some spittering and sputtering and then cut off. Have you checked for fault codes? A crank sensor would be more likely then a fuel pump issue

Glenn Beasley Chrysler Tech

I had a Dodge minivan with a pump that would shut off from time to time. While driving, sometimes when I took my foot off the accelerator the pump would shut off and not turn back on. It was just like somebody pulled the distributor wire. If I wanted it to keep going I would have to power brake on the freeway to keep a steady demand for fuel. That was a really irritating afternoon until I got it home.

Regardless, I agree with you guys. It's most likely a sensor telling the ignition to shut off. It would be simple enough to prove it by poking the fuel pressure test port to see if gasoline comes out after the engine dies.

THANK YOU for the replies... For some reason, I just have this mental block every time it comes to this vehicle. The computer didn't throw a code, so I kept focused on the fuel pump and relay. Not sure if there's a test for the crank sensor or not, but I can replace the distributor and see what happens next.... Thanks again Rick

The sensor in the distributor is the cam sensor, the crank sensor is in the transmission bellhousing. If you have no check engine light, if it is a sensor, it is probably the crank sensor.

These sensors get old and then heat cracks the wires inside the sensor and the sensor then works when cold and when they get hot and expand the wires break connection and they stop working.

Ted

Update.....: Thought I had the problem licked after replacing 5 feet of rotted and leaking fuel line, but, no deal.... New lines look nice though... Went to pick up a crank sensor, but they didn't show one, and their system pointed to a cam sensor. They were nice enough to give me the sensor "on loan", but that didn't do the trick either.

Now I'm noticing that right after it dies, I shut the key off, wait about a minute, turn the key back on, and I DONT hear the fuel pump. Wait another minute or two, then I hear the pump...

There are two things I can't seem to find: 1, The fuel pressure relief schrader-type valve, and 2, the darn crank sensor. My Haynes doesn't reference a crank sensor for this year ('95 3.0L, D.O.M.

Any suggestions? I'd really like to get the most obvious stuff out of the way, before going to the dealer. Thanks again Rick

A test you can do: After it dies and you turn the key off and back on and don't hear the pump, crank it and see if you get sparks. The same relay (ASD relay) controls both the ignition system and the fuel pump. If you get spark but no pump, the problem is downstream of the relay. If you get no spark and no pump, the whole system controlled by that relay is failing to power up. If this is the case, check the line coming to the ASD.

I had a problem on a few of my older vans ('88, '89 and '90) where the line directly from the battery + to the ASD relay did not have 12 volts (it is supposed to at all times, key on or off). On two of these vehicles it was a permanent failure, and a jumper wire permanently installed from the ASD to the battery fixed it. On the '89 it was an intermittent problem. I'm not saying that it is likely in your case, but it's worth checking.

Well, yet another update....: Before starting it up, I swapped out the ASD relay with the A/C clutch relay. Started her up, she ran for about 10 mins, then died. PI**ED me off... (Sorry Tom...) Checked the relay for 12V, it's right on.

Then I got to thinking about bad connections, etc., so I restarted her and pulled the connector from the MAF (MAP?) sensor that's attached to the plenum, behind the distributor. The engine came to a very abrupt halt. I plugged it back in, restarted it, and it's still running after about an hour or so. I also poked around every other connection under the hood, and couldn't even get so much as a misfire,or a light-flicker, so I let everything be.

Put the trans in R, D, D2, D1, P, shut it down, then checked for codes. Got a 12, and a 55.

Fixed? Not sure. Seems to not die after 10 mins. I'll let the engine cool and go out and try again. If not, off to the dealer.

Thanks to all who offered up help/advice, etc.

Rick

Well, after fixing my computer, I'm finally back online. The issue with the pump was a bad wire in the pump harness. After some time, the pump would not prime upon turning the key. That said, I figured there was a power problem. I found that the pump harness was replaced at one time, and the wires were just connected, twisted, and secured with electrical tape. Not a very good way to wire something that sits underneath a vehicle...

Needless to say, I wasn't a happy camper. But, less>>

Some of the best maintained used cars I've seen belonged to people who knew nothing about cars BUT they *knew* that they knew nothing and so never tried to "fix" things themselves. Watch out for those quick&dirty home "fixes" done by folks who should'a left it to a professional.

That's what blows my mind on this! We are only the second owners. The original owner was a rep for IBM and traveled between Buffalo and Rochester NY pretty much for the length of time he had it. If it farted sideways, it was serviced (and of course paid for by IBM)

I have ALL the service records, INCLUDING the receipt for the new fuel pump harness..... I'm certainly no technician, but I'd really like to talk to the gentleman that installed it.