TexasBlake

I'm having some unusual occasional power loss on the highway for the past three weeks. This has happened on two trips and I don't have a clue what it is since I dont know much about diesel engines.

First off, I have a '93 dually, with a Getrag. It has a turned up pump, I didn't do the work on it. And it supposedly has injectors. I think it has PODs since the owner said he put the biggest ones he could find and they were called Black Prince or somthing. I guess he means "Prince of Darkness".

Three weekends ago, I went on a trip to Houston from Corpus. This is about a 200 mile trip. So, I was driving beween 70-75 and a few times I would loose all power. The engine would drop down all the sudden and I would have no throttle response and then all teh sudden it would kick back on just as quick as it turned off. I suppose this is the fuel cutting out for some reason. It did this about 5 times, progressivly getting worse. After a while, I couldn't keep 70-75mph (around 10psi) and when I backed off to 60-65 (0 psi) it never did it. I suppose that I dont have enough fuel pressure to keep up with the demand of the boost.

When I made it to Houston the first thing I did was change the fuel filter. It had been a year since I changed the filter and it looked pretty bad. I also filled the filter up with Stanadine and let it sit overnight after I drove it around the block. It gave me no problems going home at 70-75mph.

The next weekend, I went to San Antonio, which was another 200 mile trip. I was towing my jeep and my 18ft gooseneck (about 8000lbs) and pulled 65-70 with 10psi and didn't have any problems the whole trip.

Just this past weekend, I went back to Huoston for thanksgiving. On the way there it was giving me the same cut out crap at around 70mph or 10psi. This time it was bad, it would shut off and not come back on for a good 5 seconds, slowing me down to 50mph with traffic behind me. I didn't change my fuel filter when i got home, but I let my truck sit for a few days since I went to Arkansas with my Dad. On the way home, I was going 75-80 (10-12psi) and it didnt' give me any hassles. Only time it bogged down when I going 90 and 32psi passing someone.

I have no clue what this could be. Is this my pump going bad on me? My fuel milage has been decreasing over the past few months. I used to be able to get 400 miles to the tank no problem, now I get in the upper 200s or lower 300s per tank. Usually I get 18mpg in town or so, and 14 towing. Now I get around 12 around town and even less towing. SOmthing isn't right. I don't think there is any air in the lines, I see no visual leaks.

I changed my air filter, fuel filter, oil change, etc. All the little cheap stuff. I don't want to spend $400 on a new pump if that's not the problem. Is there any way to check it? I assume some kind of pressure check. I don't think it would be a clogged injector since it only happens periodically.

Hopefully someone will know off the bat what the problem is. When this kind of problem happens in a gas engine it is usually a pump or maybe a TPS.

apache

Sounds like a fuel problem as you say. There are no TPS on stick models. With the exception of your mileage???? you might want to check the wires to the fuel shut off solenoid and KSB while your at it. theres only a few wires to the pump. the spade connectors can work loose and cause problems. Im wondering if you are getting bad fuel? PSI? you mean boost? or fuel pressure? Its cheap insurance to replace the lift pump also. Its can be had for $45.00. If it is bad it will ruin your injector pump. Once its runnin the only way to kill it is shut off fuel on yours, gotta be there somewhere. Also if your hittin 32 psi boost its not stock as you mentioned. Cant say for sure but it seems when an injector pump goes adios its gone pronto like, mine just died, no inbetweens.

TexasBlake

Yes, my psi readings are turbo boost. There's aroudn 140k on the truck.

I'll check the fuel shut off solenoid. Where is the lift pump located?

Tommy93w350

I've been in the same situation, this is also how I found my truck. In my situation, the power supply leading to the fuel selinoid has a solderless wire terminal connecttion. The wire terminal will become loose or have a bad connection.

If you can wiggle the terminal on the selinoid, most likely you are shutting off the fuel for a split second while driving. I had the same thing to happen to me

It's very scary while driving down the interstate. I guess it's the thumpy, thump, thumpy, thump rythymn of the concrete interstate that jars the terminal loose.

Pull the connection loose and clean it with a wire brush, clean the wire and selinoid. Tighten the female terminal with pliers so it is snug when pushed back together.

I hope this works

TexasBlake

That sounds like it might be it. It seems to happen when I hit big bumps in the road and that would explain why.

I thought about the fuel cut off solenoid, but never heard about them coming on and off, just heard about them quittng and never coming back.

Tommy93w350

Basicly you are just loosing power. It's just a bad connection.

This happen to the previous owner and wouldn't stop. He traded it, the car lot had a new injection pump, injectors, and lines installed. They spend $2700 for the repairs. I bought it and it done with me twice two weeks later. I researched here on this web site and started wiggling wires. I found the loose wire replace it, Fixed!!!

It done again three weeks ago on the interstate. I pulled over, got the pliers and squeezed the terminal to make snug, problem fixed.

Tommy93w350

Also, to find the right wire, start the truck, disconnect the wire near the back of the pump until the motor stops. That's the wire you want to fix.

apache

Hope thats the cure for you. The lift pump is on the drivers side of the engine back 3/4 of the way back on the block or so. Looks like a regular old fuel pump, chevy style. Ya might wanna replace this even if its the wires, again its cheap insurance. Ever have starting problems when parked facing uphill? if so, its shot. Fuel will run back away from IP. You might find 2 wires on your solenoid, if I remember correctly, 1 is a low voltage that keeps it open while running the other is a, I guess well say higher voltage for starting juice to make sure its open. either way they both need to be good. Let us know, its nice to help out somehow, cant around here it seems

1st gen Hobie

I had this problem on mine. Had to hand pump fuel for a few days b4 I saw the wire hangin loose. Almost all of my wires slide on loosley. Guess that'l be fixed in the mornin. No more worries.

TexasBlake

I havn't had a problem with it starting ever. It usually starts up on the first starter crank even when it gets down to 30. I'll price it at work and see how much it is, I figure since it has 140k on it it might be time to change it.

I havn't had time to mess with the wires yet. But I think that has to be it. It seems to happen mostly on big bumps. It would also explain why it only happens on I59 North heading to Houston in the same areas where the road sucks.

uncleroty

Definately sounds like a shutdown solenoid problem to me, especially due to no startup problems. I just took mine (wire)off, cleaned it up and pinched it back on when it happened to me. Problem solved, thanks to the knowledge of the guys here at the forum.

A little shrink wrap to prevent corrosion and you should be on your way!

Funny, when my lift pump went I didn't get any startup problems, but it sure did blow fuel out the vent hole. The stink clued me in before it got that bad I guess. (still ran perfect). Good luck with her, a free fix is the best kind to have!!

DDD

I think you should stop driving to Houston.