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‘99 Chevy C3500HD 7.4 (454ci) dually will not start

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By Decompressing
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Decompressing Enthusiast

Decompressing

Posted
Posted

Jesus, where do I begin….

first it was having issues where occasionally it wouldn’t start, it would turn over and start for a second or two, then die. 10 to 30 minutes later you’d turn the key and it would start up like there’s nothing wrong with it whatsoever.

then came the rough start, give it gas, die on you crap. After it would seem to clear out (running ok), driving down the road it would randomly run rough again.

I’ve replaced :

fuel pump x3

fuel filter x3

fuel pressure regulator

maf sensor

maf temp sensor

crank position sensor

cam position sensor 

the computer 

cap

wires

rotor

*And one thing at a time trying to diagnose with some sense of logic and common sense what the issue is

Feeling good about the last thing replaced being the cam sensor, go to start it up and …..

same f%#king thing.

I’ve checked fuses over and over, bypassed relays to check they’re functioning.

it is a dually with two gas tanks, a flat bed and a lift gate. This is my work truck and everyday it’s down the further I get behind…

I’m pulling out my hair here (or what’s left of it), and I’m about to find a cliff here to push it over, IE, I’ve had enough, I’m baffled , stumped, and it is the first time I cannot seem to find the issue, oh, did I mention frustrated? I don’t think I need to, anyone reading this would get the picture…..

HELP!!!!

Jsdirt Senior Enthusiast

Jsdirt

Posted
Posted

Uhhg - this thing got the parts bazooka blasted at it. 😳

 

You need to find out what you're losing when it dies. Spark, or fuel, then go from there. Since everything AND the kitchen sink has been thrown at this one, I'd bet on a wiring issue to either the fuel pump or ignitor (Or possibly both).

  • 2 weeks later...
Decompressing Enthusiast

Decompressing

Posted
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Posted

Well, not the parts bazooka, one by one, using a code reader and troubleshooting logic.

Yeah, I’m ‘old school’, my first car was a 1970 ‘Cuda (383ci, 4 speed, etc.).

I’m not the guy that says, “Hey, it could be this or this and this, and maybe that too…”, and replace everything. I want to know what it is, without question. It’s my opinion that people who do this kind of thing just don’t learn anything.

So back to the truck….

I’ve always had this suspicious thought that it could be the theft deterrent module on the column not sending the proper code to the computer, thus shutting down the fuel pump and injectors.

I spoke to a parts guy of 40 years knowledge at a Chevy dealer about this, he said “No, Chevy didn’t start doing that until 2006!”….

I get back to my place, and the key relearn procedure for the new computer indicates Chevy started with theft deterrent programs in 1986.

So I’m checking for codes again and what do you think I find but the first code related to the “theft deterrent code no correct”….  STFU !!!

Really?

I had to put the truck aside for now and get caught up with work, or I was gonna lose business, customers, and money, etc.

But I will get back to it when I can, and back to this site to tell the story, so if you think you may know the solution, knock yourself out and let me know here, any suggestions are welcome, with the exception of narcissistic sarcasm, unless it’s funny AF.

mjm-1957 Enthusiast

mjm-1957

Posted
Posted

Your parts buddy is wrong, See if code p1626 or p1631 is current or history in the PCM.That truck has theft deterrent and that could be giving you your problem.I dont know how to send a link to something but if you have access to GM si this is the document ID number that should point you in the right direction 803013. The TSB number is 01-08-56-002A

 

Decompressing Enthusiast

Decompressing

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6 hours ago, mjm-1957 said:

Your parts buddy is wrong, See if code p1626 or p1631 is current or history in the PCM.That truck has theft deterrent and that could be giving you your problem.I dont know how to send a link to something but if you have access to GM si this is the document ID number that should point you in the right direction 803013. The TSB number is 01-08-56-002A

 

Hey, thank you for the response - 

I know he was wrong, just shocking to know this guy is behind the counter of a reputable Chevy dealership giving bad info.

I don’t have access to the site you refer to, it’d be nice if I did for sure.

when I get back to the truck, I’ll check for those codes and let you know -

thanks again, it’s nice to know there are few out there to collaborate and confirm my findings!

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