Shuts off while driving - Stalling

[coastlogger]

I went through quite a performance with this problem and I really hate walking. To go along with this my tach started to act up although all the scantools said the senders were giving the right signal. The dealer mechanic said I needed a new instrument cluster. As it turned out we noticed that the charging rate seemed low so changed the alt. This cured the tach problem . Not sure why but one should not look a gift horse in the mouth.Didn't cure the no start/stall. I changed the ignition switch and have not had a problem since.I remote mounted the fuel driver several years ago but changed it and the pump at this time. The pump was getting close to expected life anyway.

[SteveJan]

Does outside ambient temperature have any bearing on stalling? It seems to act up when the temp. drops. It has been in the mid to upper 90's and it seem to run fine. Then when the temp drops to around 65-70 range, as it did last night the stalling starts. Or is this a coincidence? Sometimes it will restart right a way, other times it has to sit for a while a few minutes to 15 or 20 minutes.
I have a 1997 Chevy G2500 Van 6.5 Diesel. Replaced (under warranty) the injector pump in 05/01 at 48000 miles, Fuel lift pump 12/05 at 92000. Recently (last month) I replaced the oil pressure/lift pump switch at 107,000 miles (the black plastic covering was cracked/broken, don't know how, this was found out as I tried to remove the electrical connection). And last I replaced the fuel filter last week. The stalling continues. I'm guessing the FSD/PMD is the culprit, but the temperature thing is baffling me.

Thanks, Steve

[wiganwarrior]

hi,im from the uk and i have a suburban 6.5 turbo diesel.i have the same problem as 1 r 2 of the members.my vehicle will drive fine for 80 miles then it will start to cut out,on the other hand it will stall immidiately after starting.generally it will kick straight back in but occasionally it will need to be put in nueteral ignition tunned off and restarted.(it always restarts)and ive never had to have it towed back.i have had it into my main gmc dealer who scanned it and told me its the fuel injection pump thus the repair bill will be in excess of

[twaddle]

Hi wiganwarrior,
I'm also in the UK and have a 96 Diesel suburban which used to stall on a very intermittent basis.
First, Which dealer did you take it to and what codes (actual numbers) were showing when they scanned it?
Next, are you mechanically inclined and able to have a go at checking some things?
How long have you owned the truck and any history on how long this problem occurring?

When you first turn on the ignition switch, can you hear the lift pump buzzing from under the body below the drivers seat? That's assuming your Sub is still left hand drive.

Let us know and perhaps we can help before you need to spend

[wiganwarrior]

im not sure if it does kick in to be honest,niether am i mechanically minded.the dealer i went to was in manchester,ive taken it to quite a few garages and theyve come back with all diff notions.ie engine cut off switch,turbo vacuum,dodgy fuel ect

[cryodrene]

I have the common problem of the truck shutting off while driving. It is getting worse and worse. I replaced the PMD and it worked ok for a week. It shut off yesterday and I pulled out the PMD and put it in the freezer for 10 mins. When I put it back in it started right up. Drove about 5 blocks and it shut off again. This time I walked home and waited a couple of hours. I took a freezer pack for sore muscles and wrapped it around the PMD and it started right up and drove fine all the way home. I let it sit and idle with no problems for 20 mins. Then shut off even with the cold blanket I have rigged up. Any suggestions for this. I don't think it is the PMD anymore since my little experiment. Also, I noticed that when going down the highway it feels like it is struggling sometimes. Like if you were to slightly give it gas and then slow down but faster. When it does that the fuel gage starts to bounce around. Then it smoothes out.

[John Worlow]

I have a problem with the 6.5 (1994) model in a Chev. Silverado. The engine is a little hard to start and will actually shudder after warm up if you try to rev the engine to the point of maximum or intermeditate speed. Any answer for this. I have put a racor 230 filter system on the engine. Thanks John Worlow johnworlow@yahoo.com

[KillerBob]

Hey everyone. I had the same problem with my '96 6.5...cruising along fine, then either it would buck or stall completely...would usually start on the coast in neutral but not always. Sometimes it would do this 15 times across the city (not fun in heavy traffic) until I got home, while on another day I could drive 300 km with nothing. I did some research on this site and got a cooler and an FSD. Took the plug off the old FSD, hooked 'er up and not a problem since. My FSD didn't come with a resistor so I ordered a #5 from ebay..some people say you need em, some don't, but I figured it couldn't hurt. I'm glad this website is here and everyone is so helpful. If your truck is doing this odds are good this is the problem. Thanks.
Richard

[cryodrene]

A little over a month ago I purchased this after market PMD. It has worked like a charm so far. I relocated to PMD to a different location as well. I will giver an update later down the road to let you, guys know how it does. I am not recommending this site as of yet but if you guys know anything or have any feedback let me know.

[beh612]

I had trouble with my diesel shutting down. Changed the Oil sending unit and it has been 3 yrs with no other problems...... Also along the same subject I also had to run a new ground wire from near the Passenger side battery to the engine the braided ground had burnt all the fastening clips off. This new ground was done with a 12/2 romex house wire .... This also solved a shut down problem..... With the 6.5 TB diesel it doesnt hurt to pull the starter every year or slow or hard to start engine and have it redone this usually helps spin the engine a lot quicker....

[chitop1]

Hi, I need help. My truck is a 95 3500, it stalls only when its cold.
Most of the time it will start right up but will stall again. It will only run for about 30 to 40 seconds, then stall again. It will do this till I get the engine temp to 180 degrees, then it will run ok for the whole day. Sometimes it takes me 30 minutes to warm it up. Changed the feed pump and fuel filter already, still same problem.

[ronale]

Find fuel solenoid fuse 20A blown. Replaced fuse and tried to start engine.
Engine runs for a couple of seconds with rpm rising to 3000 (or more) and then shuts off again.Heavy grey smoke. No codes read in PCM. I am not able to read IP codes. Could this be a faulty FSD?


Ronale

[DmaxMaverick]

Not the FSD/PMD. Sounds like a bunch of air is getting in. Check your lift pump and its relay for proper operation.

[Robyn]

Definately be sure you are not getting air in the system.

The Blown fuse has me worried that there is something more serious going on here.
The fuse you replaced, was this for the fuel shutoff solenoid?
If the shut off solenoid goes down when the power is still on to the contols on the IP you can suck all the fuel from within the IP which would leave a void (air) the restart would be a bit bumpy but no biggy.

The solenoid is installed as a safety protocol in case there is another failure within the system. Without this device, a control failure could lead to a non controlable runaway.

The fuel shutoff solenoid may have a short in the coil. (little round unit on the front of the IP about 1" in diameter and 3 inches tall with wires coming out the upper side)

These can easily be replaced. Some times the air hat has to come off to get to the electrical plug though. Simply use a wrench or an allen key depending on the type yours has and unscrew the unit. (Wipe or blow off the area to get all dirt away) Make sure the large spring stays in the IP. Screw in the new solenoid, plug in and poof, all done.

I have had a go round with a PMD that did the scream and die thing.

I was testing some used PMD's that I got from a local shop that just replaces every one when they do a rebuild on a pump.

I was using my dually for the test and it runs great. I swapped in one PMD and the engine started, stubbled and then screamed with loads of smoke and then died.

I am not sure of exactly what goes on in the PMD to cause this but I have seen it first hand so I know it can happen.

Its an easy trick to swap in a fresh PMD and see what happens.

The New DTECH units are starting to get a good reputation.


I would definately sort out why the fuse was blown.

Possibly replace solenoid just because

Try a restart and go from there.

No codes on an OBD II system is fairly well indicative of an issue that the PCM is not actually controlling "Shut off solenoid"

The PMD can still cause issues and not trip a code even on an OBD II.

My bet is that your shut off solenoid has a short and caused the issue and the resulting "dry IP" resulted in the no fuel and subsequent wierd running and dieing.

Keep us posted

Best

Robyn

[ronale]

Thanks for reply.

The fuse replaced is in fuse-relay center underhood named 20A FUEL SOL.
According to electrical drawings the fuse is in same circuit as engine shut off solenoid (same as fuel shut off solenoid?) and FSD/PMD.
I measure the fuel shut off solenoid coil to be about 19 ohms, no short to chassis. I also applied 12V direct and I can hear it works.
This is leading me to the FSD/PMD in the same circuit. I will swap a known working PMD tomorrow.
Why do the engine speed up when starting without touching the accelerator and then shut off after 2 seconds with heavy grey smoke? Is there no control these 2 seconds of how much fuel is going to the cylinders?

I have not checked the fuel for air yet, I believe the fault is electrical.

Best

Ronale

[DmaxMaverick]

Thanks for reply.

The fuse replaced is in fuse-relay center underhood named 20A FUEL SOL.
According to electrical drawings the fuse is in same circuit as engine shut off solenoid (same as fuel shut off solenoid?) and FSD/PMD.
I measure the fuel shut off solenoid coil to be about 19 ohms, no short to chassis. I also applied 12V direct and I can hear it works.
This is leading me to the FSD/PMD in the same circuit. I will swap a known working PMD tomorrow.
Why do the engine speed up when starting without touching the accelerator and then shut off after 2 seconds with heavy grey smoke? Is there no control these 2 seconds of how much fuel is going to the cylinders?

I have not checked the fuel for air yet, I believe the fault is electrical.

Best

Ronale

This will rule out the PMD/FSD as the cause. Not to say the PMD isn't bad, but I see no indication of it yet, and it won't cause what you are seeing. The high RPM, gray smoke, then dying is a dead ringer for air. Electronics won't cause this.

[ronale]

Thanks

Ok, will check the system for air, but I am still concerned why the fuse blowed when engine shut down first time. Engine would not start until I replaced the fuse.
What is the most possible cause for air in the system? Broken lines, feed pump?

best

ronale

[DmaxMaverick]

The most common cause of air is a loose or poorly sealed filter assy cap. That is, if the fuel lift pump isn't pumping. If the lift pump is fine, then the leak will be between the lift pump and the tank sender. If it only happens after the engine hasn't been run in a while, the system can drain back to the tank (through a leak or the injectors). Usually, if you have a leak significant enough to allow air into the system, it will also leak fuel externally under pressure. First, confirm you do or do not have air in the system, then go looking for the source, according to the conditions you are getting the air. If this has only happened once, and you can't repeat it, then there's no telling what happened. Most often, it will happen right after a filter change, or other reason to open the fuel system.

I think your blown fuse and the weird start up are two separate issues. Sometimes fuses blow for no reason, but you should still investigate. Perhaps something was shorted, but now isn't??? It happens, and it will usually return at some point. Could have just been a tired/old fuse. Other possibilities include bare insulation somewhere, only shorting under certain conditions.

[Bnave95]

One issue that I can relate to on my truck when this has happend though I had a code ,yet did not show at first was the crank sensor.
Is the crank sensor in this circuit?
At the time of runaway did it also rattle really bad?

[ronale]

As far as I can see, the crankshaft position sensor is powered from the PCM. It is not in the PMD/fuel shut off circuit.
Runaway happens each time I try to start and last for about 2 or 3 seconds until it shut down. The rpm needle exceeds 3000. It does not rattle.