Please help - 95 Suburban 6.5TD stalled and won't start

[luv2rin]

Hi everyone at the Dieseltowing Resource,

I am new to this forum and sure would appreciate your urgent assistance with a stalling problem. I have a 1995 GMC Suburban 6.5 TD with 112 000 miles. In the last month, I installed 2 new batteries, a new starter, a new 4” Warpspeed (Diamond Back) Exhaust System to improve towing power, installed a new S&S PMD which is mounted on the manifold, removed the stock air cleaner box and installed a new S&S cold air intake (similar to the K&N), replaced the CDR Valve, replaced the diesel fuel filter. When I bought the car it had a 30 HP Hypertech performance chip already installed. I drove it from OH to IL a few weeks ago and it went like a dream!

The car has been going really nicely until suddenly this afternoon, it stalled for the first time since I have owned it. What happened is as follows: The car was parked here in Chicago. It has become quite cold here. I went to start it - it started well and easily. I drove it slowly for about a half mile and was doing about 15 mph, when suddenly it lost power and the engine died in the middle of the road. I tried to start it again - it cranked and cranked but would not fire up. I then noticed that the glow plug light does not come on, nor does the check engine light come on. After a few seconds of trying to start it, the batteries started making a clicking sound, as if the batteries are dead. I then tightened up all the battery connections to make sure nothing was loose - the clicking sound stopped, but it still would not start. The batteries are still fine and are new. I checked the fuses in the fuse box under the hood - they all seem fine.

This happened about 3 hours ago - I have been back to the car to check if it will start and still nothing - the glow plug light and check engine lights do still not come on. My car is now immobile on the side of the road fortunately in a residential area, and I was wondering if you kind gentlemen may have some ideas what I can check for before calling a tow company to tow me to a garage, which I would like to avoid if at all possible..

Thank you very much - looking forward to your replies…

 

[DEERE3594]

Can you check codes on it?

 

[luv2rin]

I never have checked codes on my diesel - I'm not too mechanically inclined and maybe a bit unsure how to do it. Do you feel that doing this is going to be the best/only way to trouble-shoot my starting problem?

Thanks again,

 

[DEERE3594]

hmmm.... Im not sure where Id start... How old is the PMD/FSD?

 

[Acesneights1]

Check the fuse for the PCM/ECM(for get which it's called). If the computer fuse is blown the glow and check engine light will no work but truck will crank but not start. I just saw the exact same thing you described a few weeks ago in NY. Guy changed the IP and all it needed was a fuse. Start there, report back.

 

[nvmtnlion]

Welcome to the forum. I would suggest several things:

1. It has been proven many times over that putting the PMD/FSD on the intake manifold still exposes it to lots of soak heat and can cause it to fail.

2. Ignition switch, did you hit a bump or rough stretch of road when you died? The ignition switch is a known failure method.

3. Are your ground connections clean and tight? Is your PMD/FSD grounded?

4. Fuel pump, are you getting fuel out of the water drain valve mounted on the coolant crossover while you are cranking the engine?

I hope these suggestions help ya!

 

[Schwind]

Here is the procedure for checking the DTC codes. It is simple to do with the OBD-I system which is what you have on your suburban.

http://www.thetruckstop.us/forum/showpost.php?p=50700&postcount=3

 

[JiFaire]

Here's one that's a little more graphic...

http://www.thetruckstop.us/forum/showpost.php?p=47918&postcount=1

Have you completely removed your battery cables (especialy the dual cable on the passenger-side battery)? They get grungy easily, and that one has a little copper donut in between the flanges that often gets corroded and stops current.

 

[luv2rin]

Thanks everyone for the fast responses. Could I please ask you two silly questions: where do I find the fuse for the PCM/ECM and where do I find or how do I check the ignition switch? I have a 1995 GMC Suburban....I have checked all the fuses in the fuse box which is located under the hood on the driver's side, and also inside the car on the driver's side entrance - the fuses are all fine.

I have also been back to tighten up the battery terminals - the positive on the passenger side was a bit loose, so I tightened it real good. I also made sure the ground on the PMD/FSD was tight.

Thank you again....

 

[JMJNet]

I have also been back to tighten up the battery terminals - the positive on the passenger side was a bit loose, so I tightened it real good. I also made sure the ground on the PMD/FSD was tight.

Thank you again....

Where is this ground? If it is on your SS PMD heatsink, you need to move it back to where it comes from "on top of the" Injector Pump.

 

[luv2rin]

In reply to the question from JMJ Net, the ground for the SSD PMD heat sync is on the heat-sync itself. I tried to move it back to the spot on top of the injector pump, but the black wire is too short - do I need to add more wire or how can I get it back on to the pump? Could you also please tell me how do I check if the PCM/ECM fuse is still good - where do I find it?

Thanks again...

 

[NVW]

In reply to the question from JMJ Net, the ground for the SSD PMD heat sync is on the heat-sync itself. I tried to move it back to the spot on top of the injector pump, but the black wire is too short - do I need to add more wire or how can I get it back on to the pump? Could you also please tell me how do I check if the PCM/ECM fuse is still good - where do I find it?

Thanks again...

PCM/ECM fuse is in the fuse box you checked under the hood. Leo

 

[JiFaire]

If he can't get it to crank, he has either got battery problems or cabling problems.

Or ign switch, but it went funny pretty fast for that...

 

[luv2rin]

JIFaire, the engine does crank strongly - it just won't fire up. The wait to start light (same as the glow plug light?) does not come on, nor does the Check Engine Light. I checked all the fuses in the fuse box under the hood, including the ECM fuse (I think) and the fuses are fine.

Do you think that what I have is a battery/cable problem? Both batteries are about one and a half months old...I bought them new at Walmart - or is it something else?? As at this moment, nearly midnight central time, I am still unable to start the car...tomorrow morning I'm kinda stuck...dang....dang...dang....

 

[Acesneights1]

PCM/ECM fuse is in the fuse box you checked under the hood. Leo

I thought I changed one in the fuse panel inside by drivers door but I could be wrong. Just look on the diagram for either ecm or pcm. forget which it was. It was one of the type you could see through though not a self resetting one. Use a test light .

 

[Slim Shady]

Lets get back to basics, 1995 is DS4 pump.

Either the vehicle has fuel or it doesn't, we know it cranks over, so lets get out the old WD 40 spray can and give it a shot while cranking it, the truck should start, If so we know it will run if we get fuel to it. Now we have a place to start.

I would also look at the starter fusible link and see if one of them hit the exhaust, also the computer ground on the battery is a must, it can corrode and cause the vehicle to die, (since we have no glow plug or ses light) and the truck was running when it quit. Basics first.

Take a deep breath, it can be fixed with everyone's help. We have some of the best technicians around on the 6.5 diesel.

 

[Drew]

Sounds like a fuel delivery problem to me as well.

Could his lift pump have died? On my old 94 there was a lift pump on the frame rail under the drivers side.

 

[RadioMan]

Lack of WTS & SES lights sure seem to point to an electrical problem.
ECM-B fuse feeds the ECM & the Lift Pump. The upper yellow fuse it the ECM-B, btw.
Does the Lift Pump run?
How are you checking the fuses? Just looking at them is sometimes very misleading... An Ohm meter (multi-meter) or test light is the only sure way to check them. Corrosion of the fuse contacts or the contacts of the fuse holder will also keep your electrons from their appointed path.

Pics are from my '95 1 ton, so things might be different on your Sub - I don't know.
I've also removed the cover from the LP relay - Makes it really easy to bleed the fuel system and/or check the LP. I have a new one as a spare (just in case) but since the relay is under cover anyway I don't think it will be a problem - Hasn't been yet :smile5:

 

[Acesneights1]

That's what Im sayin. No WTS or CEL plus no fuel to me indicates PCM not working. Corroded wire from Alt to bat on pass side can cause fuse to blow. Just had this problem with someones 94 in NY. Exact same symptoms. If I read the intial post correctly he is cranking over but no start, no WTS no CEL and no fuel to inj. Could swear fuse I found blown was in fuse block in cab by drivers door but could be wrong. I will look at mine later. That to me seems like logical place to start. If you can't see a CEL light or communicate with PCM through scan tool or paperclip then you can't go any further until that is resolved. Must verify PCM is alive and talkin to the truck....

 

[Schwind]

No wait to start light and no ses light problem on my truck (granted it's a 94) was the fuseable link that powers the glow plug controller and OPS. these are the 2 things that I know of that the fuseable link supplies power to, there maybe other system components that I don't know of. Once the link was replace all systems worked. Just my two cents.