# 2002 6.0L motor died



## ProLawn Outdoor (Dec 15, 2008)

Heres the deal, just picked up a new (to me) truck a couple weeks back. 02 2500hd 6.0L, 100k miles. Driving the new truck last night, going down the freeway 55 mph, engine running just under 2k rpms. All of the sudden it won't go over 50 mph and starts cutting out, almost like its not getting fuel. When I gave it gas it would almost slow down. I limped it home going about 45 mph down the freeway, get off the highway, I'm pulling into my neighborhood and the motor dies. Right before it cuts out, like right before the check engine oil pressure light comes on for a split second, then motor dies. Im thinking oh sh**:realmad: We were able to push it down the street to my house. I tried starting it, it turned over and idled real rough for a couple seconds and died. 
Heres where I'm stumped. All gauges in check, oil pressure good, coolant temp in check, no check engine light or any codes showing on the dash until right before it died, truck was running great. Checked the oil, (it does need an oil change), but it only looked a quart low at most. To me this raises a flag as something in the fuel system id like to say fuel pump in particular. Does anyone have any ideas? Keep in mind it was about 5 degrees outside last night. Lucklily I have access to a scan tool, fuel pressure tester, etc at work, Im just wondering where to start. Any help is greatly appreciated!! Merry Christmas!


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## CAT 245ME (Sep 10, 2006)

Sounds something like what my truck was acting like a year ago, it would idle rough, press the gas peddle and it would want to shut off.

The problem turned out to be two plugged catalytic converters, a local garage cut them out and replaced with straight pipe. Since then the truck has run great. Mine is an 03 2500HD with the 6.0


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## White Gardens (Oct 29, 2008)

My first guess is the fuel filter,do you know when it was changed last?

5* is pretty cold. Fuel could have gelled up on you.



...................


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## Plowtoy (Dec 15, 2001)

I highly doubt that the gas gelled and having both converters plug at the same time is also unlikely (although not impossible). I would say to start with the simple stuff. Look to make sure that your intake piping hasn't come off and between the air filter and engine. If so, the MAF sensor would be sending false readings. I would bet that you have more like a crank position sensor failing or an ECM (computer) problem.


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## dieselss (Jan 3, 2008)

common issues with the 6.0s,,,,,,,,throttle pedal,,wiring from this to the computer,,wiring from the puter to the throttle control,,and the throttle control itself.
will not gernerally set a code. still need to hook up scanner and see if theres any codes.
another issue as what was aleady said is the cam/crank sensor


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## ProLawn Outdoor (Dec 15, 2008)

Thanks for the help everyone!
White Gardens- No idea when it was changed last, Like Ive said Ive had the truck for 3 weeks. The previous owner was not mechanically inclined and took it to the dealer for all service so I'm guessing its been replaced but who knows. Probably start with that cuz its cheap, easy, and needs to be done anyways.

Plow Toy- Any obvious way to know if it is a crank position sensor, ecm issue? Probably the first thing I'm gonna do is go at it with a scanner, will a code come up? Do you have any suspicion towards a fuel pump? I Know I can rule that out quickly with a fuel pressure test, just curious your thoughts. Ill check out the intake and see what I find.

CAT 245- Ive heard of that before, I know its probable but will probably be the last thing I check. Although it would be the easiest thing and would give me a good excuse to put in some aftermarket exhaust

dieselss- Ill look into that, thanks for the help.


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## djagusch (Oct 15, 2007)

Check fuel pressure, also if the regulator is on the rail that could have issue besides the fuel filter.

If for some reason the engine is toast I have a extra one from a 01 I could sell.


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## ProLawn Outdoor (Dec 15, 2008)

djagusch;1547278 said:



> Check fuel pressure, also if the regulator is on the rail that could have issue besides the fuel filter.
> 
> If for some reason the engine is toast I have a extra one from a 01 I could sell.


Ya I agree those fuel pressure regulators of that year are junk, they get gummed up from all the alcohol in the junk fuel they have these days, not designed for the alcohol in todays gas. Its like a 6 dollar part ill probably pop that in and cross my fingers that its something that small. I hope the engine isn't toast, but i'll keep that in mind in the worst case scenario. Just curious what you would want for that motor?


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## mn-bob (Sep 18, 2012)

When you first turn the key on can you hear the fuel pump run ? If you don't have the fuel pressure gauge you can try and tap on the bottom of the tank and listen for the pump when you cycle the key on and off From what you have told us it sounds like a fuel problem to me. Good luck and let us know what you find .


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## djagusch (Oct 15, 2007)

ProLawn Outdoor;1547325 said:


> Ya I agree those fuel pressure regulators of that year are junk, they get gummed up from all the alcohol in the junk fuel they have these days, not designed for the alcohol in todays gas. Its like a 6 dollar part ill probably pop that in and cross my fingers that its something that small. I hope the engine isn't toast, but i'll keep that in mind in the worst case scenario. Just curious what you would want for that motor?


Idk I would check part-part.com and knock alittle bit from the salavage yard prices. Id rather keep it around.

Fyi I just tried starting my 05 van w/6.0 and it seems like the fuel line froze up on it. Hadn't been ran for a few days only 1/4 tank of gas on a slight slant.


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## nathan11507 (Dec 3, 2010)

i had a 2002 8.1 in a avalanche and the crank sensor went in it but didnt show nay troubles that ur showing it would die but then fire up again after a couplke mins...but before trading it in i had the same exact issues ur having and the fuel pump was shot to hell only pushing 2 -5 psi throught the pump.....and they aint cheap


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## Plowtoy (Dec 15, 2001)

dieselss;1547205 said:


> common issues with the 6.0s,,,,,,,,throttle pedal,,wiring from this to the computer,,wiring from the puter to the throttle control,,and the throttle control itself.
> will not gernerally set a code. still need to hook up scanner and see if theres any codes.
> another issue as what was aleady said is the cam/crank sensor


I have never heard of that... I think that can be a good possibility as long as your throttle is fly by wire and not a cable. I believe you could have either in 02, just depended on when it was built



ProLawn Outdoor;1547253 said:


> Thanks for the help everyone!
> 
> Plow Toy- Any obvious way to know if it is a crank position sensor, ecm issue? Probably the first thing I'm gonna do is go at it with a scanner, will a code come up? Do you have any suspicion towards a fuel pump? I Know I can rule that out quickly with a fuel pressure test, just curious your thoughts. Ill check out the intake and see what I find.
> 
> .


If you hook up your scanner, you should be able to see rpm while cranking, if not, that is a real good sign that the crank sensor is not reading. Fuel pumps, in my experience, typically don't fail while the engine is running. Seems like every one I have ever changed has failed at the gas pump just after the tank was topped off The only way to know for sure is to put a pressure tester on it and see what the pressure is. Good Luck!!


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## theholycow (Nov 29, 2002)

Yikes, this thread....ok, here goes:

Plugged cats: No. Plugged cats would show up as losing top-end HP and might throw a code, but it won't affect highway cruising or starting.

Fuel filter: No. Again, top-end HP, maybe a code, no effect on cruising/starting.

Fuel gelled: No, but if there's a whole lot of water in the fuel, the water could have frozen. Good line of thought.

MAF false readings from disconnected intake plumbing: No, it would detect that, throw codes, and go into open loop mode running on predefined tables instead of sensors.

Crank position sensor: All reports I've ever seen have been "It was fine the last time I drove it, now it won't start", but I guess it's possible.

ECM (actually GM calls it PCM) problem: It's a popular diagnosis but almost never correct.

Throttle pedal/throttle control: 2002 had cable throttle (unless they gave DBW to the 6.0 one year earlier than the 5.3/4.8). All there is is a Throttle Position Sensor on the throttle body. If there were false readings or a failure there, it would throw a code and run pretty much normally. (For a 2003+ with drive-by-wire, the common problem is the Accelerator Pedal Position Sensor, with some different symptoms and a "Reduced Engine Power" message.)

Fuel pressure regulator: Getting close, guys. This is a common diagnosis for hard starting and supposedly a common problem with these GMs but it always ends up being a check valve at the fuel pump.

Fuel pressure regulators not designed for 10% ethanol: My 1980 Buick was designed for 10% ethanol, as has every GM since then and probably a lot before.

Listening for the fuel pump: DING DING DING WE HAVE A WINNER! Listen for the fuel pump, but even if it's making noise that doesn't mean it's developing pressure and pushing volume, so get a fuel pressure tester. Harbor Freight sells ones for $20 that works perfectly on these engines, or get a loaner from a parts store.

Checking part-part.com: I think you meant car-part.com but the engine doesn't need to be replaced anyway.

Fuel pumps ain't cheap: Correct. Also, *don't buy an Airtex or other aftermarket brand*. Buy AC Delco. The AC Delcos are bad enough, 100,000 mile death is normal especially if the previous owner liked to run the tank to empty before filling, but those damnfool aftermarket ones are worse, often defective from the factory...don't know why they can't get this fuel pump right.

Fuel pumps failing while driving: Happens often, and happened to me.


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## ProLawn Outdoor (Dec 15, 2008)

Holy cow- Thanks for the help. I replaced a fuel pump on my previous 2002 6.0, I did buy a delco one and if i remember right it was 250-300. I later on had to replace the regulator and the guy at the parts store told me he sells tons of them for GM's because the alcohol on the fuel has a reaction with the material inside it and it gums up the inside? Seemed to make sense but who knows. 

Im gonna go after the fuel pump and pressure regulator and rule out the fuel system before anything else, to me it makes the most sense. Luckily I have access to a pressure tester at work as well as a scan tool so that will be easy. Again, thanks for the help!!! Ill keep you updated on what I find.


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## theholycow (Nov 29, 2002)

If you confirm that pressure is low, one test that can tell you the regulator is bad (but this test can't promise you that it's _not_ bad) is to pull the plastic vacuum line off the top of it while it's running and see if fuel drips out. If fuel drips out of the plastic vacuum line, the regulator is definitely bad...if not, it may or may not be bad. Anyway, the symptoms you have are the symptoms of a dead fuel pump.

I don't doubt that they sell loads of fuel pressure regulators, people replace loads of them...then they post again saying it didn't help. Besides, alcohol doesn't gum anything up, it cleans the gum out of everything. It's an even better solvent than plain gasoline.


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## Plowtoy (Dec 15, 2001)

theholycow;1547786 said:


> Yikes, this thread....ok, here goes:
> 
> Plugged cats: No. Plugged cats would show up as losing top-end HP and might throw a code, but it won't affect highway cruising or starting.
> 
> ...


Easy killer... Just trying to help. Drivability has never been my strong point but with out seeing the vehicle, you know as well as I do that its almost impossible to give a correct diagnosis. Give me a mechanical driveline problem and I'll nail it almost every time. I will agree with you on the aftermarket fuel pumps, usually work good for a couple months and then loose pressure.


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## mnglocker (Dec 24, 2008)

Sounds like a F/P to me. As the other have said, get a pressure tester and the specs on your truck and test it out. If it comes back bunked, get the delco pump. I've played this game a dozen times on an old ford of mine, airtex pumps are crap to put it nicely. Not even 100 miles out of the last 2 I had. 

Also, before you dig in, grab a new set of tank straps, murphy's law will have effect and your old straps will break when trying to put the tank back up. You'll also need to replace the fuel filters to keep a warranty on the new pump btw. 

And never let your tank get below the half way point if you want your pumps to last.


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## theholycow (Nov 29, 2002)

^Another option, which I prefer, is lifting the bed and leaving the tank in place. The bed bolts are decent quality and won't be as rust-seized as every other bolt on the truck, you don't have to struggle with the pump fittings and stiff hoses while laying under the truck or sloshing fuel as you lower the tank,.and the tank is held solid while you struggle with the rust-seized fuel pump lock ring. Working alone you can just lift one end of the bed at a time by hand and stick blocks under it/slide it back until you have the working room you need; if you have a couple buddies (or one strong one) or a decent tree branch and rigging you can take the bed right off the truck.



Plowtoy;1547892 said:


> Easy killer... Just trying to help. Drivability has never been my strong point but with out seeing the vehicle, you know as well as I do that its almost impossible to give a correct diagnosis. Give me a mechanical driveline problem and I'll nail it almost every time. I will agree with you on the aftermarket fuel pumps, usually work good for a couple months and then loose pressure.


Sorry, didn't mean to come on so strong...I've been doing forums for a LONG time and never have managed to get much better at avoiding that. Sorry to anyone else who might have taken it that way too, I didn't mean it that way.


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## ProLawn Outdoor (Dec 15, 2008)

I really like the idea of lifting the bed. Last time I did it, really is a PITA laying under the truck, juggling the sloshing fuel tank while trying to get all the hoses and BS on the top of the tank disconnected. And the worst part of it was I got it all put back together and as I'm throwing away trash I realize I forgot the rubber o-ring that goes around the top of the pump. So I got to do the whole thing AGAIN!!! 

Im sure I could even use the two post rotary lifts at work to lift the bed right off as well. Im hopefully gonna grab a fuel pressure tester at work today if possible and do the test tonight, then I will know what lies ahead of me.


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## Plowtoy (Dec 15, 2001)

theholycow;1547935 said:


> Sorry, didn't mean to come on so strong...I've been doing forums for a LONG time and never have managed to get much better at avoiding that. Sorry to anyone else who might have taken it that way too, I didn't mean it that way.


No hard feelings, I know everyone means well. Thanks for manning up:waving:


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## 2COR517 (Oct 23, 2008)

White Gardens;1547153 said:


> My first guess is the fuel filter,do you know when it was changed last?
> 
> 5* is pretty cold. Fuel could have gelled up on you.
> 
> ...................


Gasoline gelling at 5*?


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## White Gardens (Oct 29, 2008)

2COR517;1548810 said:


> Gasoline gelling at 5*?


For some reason I was thinking I read that it was a diesel truck. I think what got me is the term "Fuel" he used in the first post.

I've always heard "fuel" used for diesels and "gas" used for gassers.

Regardless though, I had an S-10 that sat a lot one winter when we had a massive winter. I went to go start it and there was probably water in the system and it froze up on me. This is right when people were having big problems with ethanol fuel and a mechanic I talked to said that they were having tons of vehicles come in with water in the system due to the ethanol.

Doubt this is the issue here, but wouldn't be surprised if it was.

...............


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## carkey351 (Oct 18, 2010)

X2 on the fuel pump internet diagnosis...I just did one with my boss who spent almost 2 weeks trying to rule it out; and in the end it was the fuel pump!. Guess how we replaced it: yes we took the box off. yes, you will spend more time removing the box than replacing the pump; but it is so rewarding to know its done and is easy! once you get the box off (i've done it alone on a short box) it's literally a 5-10 minute job! I have done about 6 fuel pumps by crawling underneath and have done 2 with removing the box and I won't go back to crawling underneath to drop the tank -ever! (unless I have to)....so good luck, by all sounds of it a new fuel pump and you will be golden (a 2-3 hr project in a heated shop)...


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## ProLawn Outdoor (Dec 15, 2008)

Just an update for everyone, It was the fuel pump. Replaced it and hooked everything up and it fired right up. I replaced the regulator and the filter just to be safe. I was able to get it done just in time to plow, trucks been running great since. Thanks for all the help everyone!


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## mn-bob (Sep 18, 2012)

Glad to hear you got it fixed did you end up taking the box off?


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## ProLawn Outdoor (Dec 15, 2008)

No my buddies that were helping me do it insisted on dropping the tank instead of puling off the box. We should have just pulled the box though, it really would have been much easier.


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## mn-bob (Sep 18, 2012)

Glad you to hear you got it fixed .


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## theholycow (Nov 29, 2002)

Should have gotten the bed all ready to go and partially lifted before your buddies arrived, then they would just lift. Anyway, glad you had success.


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## BigLou80 (Feb 25, 2008)

theholycow;1547786 said:


> Yikes, this thread....ok, here goes:
> 
> Plugged cats: No. Plugged cats would show up as losing top-end HP and might throw a code, but it won't affect highway cruising or starting.
> 
> ...


What he said!


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