Any Diesel Mechanics Out There

peternap · February 25, 2009, 01:41:38 PM

I have a 95 Chev 2500 with a 6.5L Diesel. (The Green Hornet)

Recently, it was losing power and I had some problems with getting across the mountains.
Redover Farms thought the air or fuel filters, or both might be dirty. I changed them and it cured the power problem (Thanks John).

Since then I have had a different problem on two occasions. Before I explain the problem, when I changed the fuel filter, I did fill the chamber with fuel. I did have to pull the new filter once to re adjust it so I may not have gotten it exactly full. Don't know if It's an issue but internet diagnosis is hard enough without all the facts.

The first problem I had was a week or so after changing everything out. I hadn't driven it much at that point. I drove about ten miles to cut some wood. It was rough getting in there and I had to drive over a lot of stumps and mud. I cut the wood and loaded the trailer and started out.

While going through a tricky section where I had t gun it a lot and then back up several times.....It just stopped (The engine) No sputtering or stumbling, just like I had turned the key.

It would not restart. I got out, looked under the hood, cussed for a few minutes and kicked the bumper (Normal diagnostic procedure

)

Got in and cranked it. No sign of life. I tried again and it started like nothing had ever happen.

Drove it a few more times on short trips with no problems.

Last week, I went to get wood at another place. Started fine and drove fine. I stopped at a saw shop to check their prices and gabbed for a half hour. Got in the truck and it started like a charm. Went to get back on the highway and traffic was heavy so I had to step on it to get out.

Got on the road and was speeding up...and it just died again.

I coasted to a stop and repeated my diagnostic routine. Got back in and tried three times. First two times, no sign of life. I floored the pedal and it started perfectly

It did stumble for about 50 feet and then ran like usual.

ANY IDEAS?

cordwood · February 25, 2009, 01:57:12 PM

Check your fuel pressure from the boost (lift) pump down on the frame rail. There should be a test port on the top of the engine.
Also there have been some that lose voltage from the key switch that just shuts them down, If your pressure is good and the filter is 75% or more full I would start checking the electrical side.
Bad news is a man near me had a 96 that was doing that and after MANY trips to the dealer and a few thousand dollars of replacing parts he finally just sold it with the on/off problem so we never did find out exactly what the problem was.

February 25, 2009, 02:10:13 PM

Thanks Cordwood. I see if I can find a pressure gauge this evening. I'd leaning toward the electrical end. When I bought it 4 years ago, it had been setting for a while. The fellow that owned it was a Catipiller mechanic and died. His son in law was selling it. Half way home it started sputtering and spewing and got so bad I didn't think it would get back. I called the seller and he said it was water in the fuel. That wasn't true because it did it several times after.

There is a gang of wires running over the block and when I would yank on them, it ran fine, I checked every wire with a fine tooth comb and never found a problem. It also quit causing problems and I didn't have another one until this started.

bayview · February 25, 2009, 02:59:37 PM

I had a similar problem years ago with a Ford F-700.

Does this engine have an electric solenoid for the fuel shut-off valve? The Ford did . . . The solenoid was not working properly - shutting fuel off to the engine. Or, maybe the wire to the solenoid?

Redoverfarm · February 25, 2009, 06:10:04 PM

Peter it sounds like a Ford. Don't tell Glenn that. Anyway mine had a defective Camshaft Sensor. It would just shut dpwn completely. After sitting a little while it would start back up. Really intermitent and no pattern. Then it went out completely. I had the Ford garage tow it in and replace and it was fine after that. They didn't admit it was defective. Then low and behold Ford came out with a recall and I got all my money back.

I am not sure whether Chev or GMC have those but a call to the dealership would tell you.

February 25, 2009, 07:32:54 PM

I've had a similar problem. The codes read cam position sensor. After replacing 3 time the mechanic noticed how rough looking the wire harness was and replaced the harness. No more issues after that.

Mine was a Ford, and worth fixing.

MountainDon · February 25, 2009, 07:40:58 PM

I'd bet money it's the sensor. Gasoline burning Jeep 4.0 6 cylinder engines have a chronic problem with the crankshaft position sensor. Symptoms include the stopping for no reason at all... just like turning off a switch. It's one of the things I carry as a spare along with the tools required. Others are running like crap. Cures itself sometimes; for a while.

glenn kangiser · February 26, 2009, 12:49:46 AM

Sorry guys - I drive a Dodge Cummins Turbo Diesel and never have those problems.

OK - so much for the lying.

Could have dirtied the new filter sloshing water in the tank. I haven't worked on a Chevy.

peternap · February 27, 2009, 10:27:51 AM

Well, it did it to me twice yesterday.

It has a pattern. I got in it in the morning and it started fine. I drove 100 miles with no problems. I stopped for about 30 minutes. It started with no problem and after about 30 seconds....died. after 4 or 5 minutes, it started fine and I drove about 20 more miles with no problems. I stopped again for about 3 hours.

When I started it this time, I needed to hook up a trailer so I let it idle. After a minute, it quit.

3 minutes later, started fine and I drove another hundred and twenty miles with no problems.

I'm going to have it scanned today but I don't have much faith in that especially with the system the truck has.
Then I expect to start replacing parts. Since this started when I replaced the fuel filter, that's first. The think has a funky gasket that I had a lot of trouble getting positioned right. I'm wondering if it isn't sucking a little air.

If that doesn't do it....on to other parts

February 27, 2009, 11:09:26 AM

Just a little thought. If the key switch is bad it won't show a code, It just thinks you shut it off. One more thing I just remembered on another GM was there is a seperate hot wire for the electronics from the battery, Make sure it is in PERFECT shape, sometimes they can have a problem a few inches down from the terminal. Even though the truck cranks fine it don't mean the brain is getting enough juice. It would show a code like "recent voltage disconect". $:-\$

Sassy · February 27, 2009, 01:22:59 PM

I had a Cutlass years ago that would do that - it would even shut off while I was driving down the freeway - never did find out what caused it...

My 2000 Mercedes SUV used to do that anytime I was on a bumpy road - all of a sudden it was dead. Not good when you are on narrow, windey, mountain roads. One time I was sitting in the car with it idling - I bumped the keys & it shut off. Discovered that all my keys were too heavy & a bump would cause something inside to lose contact - my solution was to just have the car key/alarm & house key on that ring. I'd brought it to the dealership several times, they never could find anything wrong with it. There was even a recall on the starter that they replaced, did nothing to stop the problem until I took all the other keys off.

glenn kangiser · March 01, 2009, 05:27:09 PM

Reminds me of the lady who used to pull the choke knob out to hang her purse on.

cordwood · March 01, 2009, 06:23:05 PM

HaHaHaHa!!!! My Mother used to hang her purse on the dist. advance cable till it bent and the mechanic she always went to finally figured out her "Comes & Goes" problem