Injector problems

[Murray the Cop]

It seems that this is the big problem with the Duramax. Is it inevitable or do the secondary filters give us more life? I read the injector job is labor intensive but it seems to make up for half the cost. Will the price of the injectors come down with time,after market etc.,or is this just wishfull thinking. Is GM working on a fix for us that have the older model trucks or is it a case of,buy a new one if you want the upgrades? It's hard to be happy with a truck that cost so much and has this problem looming. My reasoning for buying the diesel was not only to tow my 5th wheel but for longevity.Trouble free longevity that is. I know that maitenance is a given on any vehicle but that 5000 scares me.

[hd90rider]

Murray the Cop, I dont know what all has been done to your truck, mine has only a by-pass oil system,k&n air filter,& an extra fuel filter on my in-bed tank. This is a working truck criss-crossing the US every week,pulling all size's of RV trailers. In 278,000 miles i have only had 2 injectors go bad, however, when the 2nd went bad my service dept.also found the pump getting a little weak so they replaced all the other injectors & the pump. Would the others have failed?? Probably at some time in the future, but my 1st failure was at 215k & the second at(i think)225k. How long should they last?? I'm not sure. But with all the work this truck has done I expect some things to go bad.They also do on the other two brands( cant bring myself to call out their names)!!! Yes the injectors are the most expensive I have seen and hopefully this will be remedied. I question the use of all these boxes people are using, as a probable cause of early failure??..I am not an expert,just thought I would let ya know how mine has lasted..

[Murray the Cop]

I have an ams oil air filter,a 4 inch exaust,a quadzilla triple guage,and the juice w/atitude on the truck right now.An amsoil bypass system in the box(waiting for warmer weather) and a ******** Pre CAT filter on the way.The only other mod I am thinking about,or should I say saving for,is a tranny upgrade. I hope that the injector problems are not linked to the power upgrades because the truck is much more fun with them. Thanks for the info,I want this truck to last untill I retire. 10 MORE YEARS!!!

[mtomac]

what's with the ******** 's

[Murray the Cop]

Nick&*^&. I guess I can't post the name . That's funny because in the thread I started"secondary fuel filter" Its posted in the first few replys.How do those BFG's work on the stock rims?

[OC_DMAX]

hd90rider

Just curious about a thing or two,,, when you refuel your vehicle, do you fill the 115 gal "cruising" tank and then transfer from that tank to the OEM tank through the extra fuel filter? Or do you fill both tanks and use them independently. Secondly, what type of fuel filter do you have on your 115 gal tank?

There is only one other person that I have come across in these forums that has come close to rolling up the mileage you have on a DMAX. That is Captainmal. ( There quite possibly are others). Anyway, he had no supplemental filtering. His injectors started to fail at about 120K miles and by 160K miles he sold his Duramax truck. He delivered trailers like you. Both of you ran stock engines (no power boxes).

Though two trucks are a statistically small sample, You did go almost twice as far before some injectors needed replacement (and you possibly had additional filtering).

Regards,
Alan

[KERMA]

Originally posted by Murray the Cop:
Will the price of the injectors come down with time,after market etc.,or is this just wishfull thinking. Not wishful thinking. Aftermarket to the rescue soon....
;)

Just ask the VW TDI guys. :cool:

[glclary]

Well said Murray. It seems logical that injectors could wear out. They are after all, moving parts. The 5000 bux thing has us all kinda freaked out.

Thanks for posting Bill. It gives me hope. 278k huh? Thats about when I thought I would trade. The ashtray ought to be about full by then. smile.gif

Regards,
Lee

[roadrat68]

i cant tell you how many time i had problems with my injectors on my 03 i went through 6 injectors 2 in the first 8 thousand miles and then 4 at the 35 thousand mark finaly GM bought my truck back.

[mtomac]

Murray the Cop,

the BFG's are fine on the stock rim if you run a little lower pressure for more even wear. I run 50 in front and 40 in back. They are a good all around towing, truckpulling, dragracing, rain, snow, daily driving tire.

[SoCalDMAX]

OC_DMAX,

I see what you're saying. I agree, 2 trucks is an awful small sample, but if Bill is filtering his fuel between the aux tank and main tank, it could explain the difference in injector life. It also agrees very strongly with what George Morrison has been saying.

Regards, Steve

[OC_DMAX]

This is just one comparison. However, we have two individuals who rolled-up a lot of miles on their "stock" trucks in a very similar manner.

One vehicle went about 120k miles then lost an injector and over the next 30k miles had multiple injector failures. This truck used only the factory OEM filter. No supplemental filtering.

A second vehicle went 215k miles then lost an injector, 10k miles later lost another injector and within 60k miles had them all replaced. This truck May Have Had (??) supplemental filtering down to the XX micron level (??).

Since both individuals are driving cross country and pulling trailers, on the average, the quality of fuel they are buying should be about the same, the quantity of fuel per mile should be roughly the same and the stresses on the engines should be roughly the same. A good situation to compare.

I find it interesting that one truck went almost twice the miles before the failures started to happen. However, once the failures did start to happen, the sequence of further injector failures was similar and happened rather quickly thereafter.

I have read several SAE papers on fuel filtration for HPCR fuel injection systems. One in particular (SAE Paper # 980869 - High Pressure Injection System Wear Study) evaluated a Cummins fuel injection system. The study varied the particle count / size of the contaminants within the diesel fuel. For a given particle count / particle size they would run the engine and measure the injector wear. What they ended up with was a set of graphs that showed injector wear vs hours of operation for different particle sizes and contaminant concentrations. From this data, they derived an equation that predicted a normalized wear number as a function of particle size and particle counts.

So, what did I carry away from reading the above paper,,, what stuck with me from the study was that injector wear is integrated over time. The equation (which was derived from real test data)implied that by cleaning up the fuel by One (1) ISO Code for each particle size, the wear on the injector was decreased from 25% to 50% (depending where on the curve you were). (A note: The 15/13/10 ISO Code for that George Morrison has been postulating as a goal is roughly the mid-point for the equation, meaning anything above 15/13/10 results in above normal wear and anything below 15/13/10 is less wear)

How does the above apply to the situation of truck one and two above? If truck two had some form of supplemental filtering, I would expect it to have at least a Two (2) ISO Code reduction in particle count. That implies roughly a 50% (factor of two) reduction in wear. Magically, truck two above went almost twice as far as truck number one before injector failure started occuring. Once the injectors were worn, then mulitiple failures started occuring on each truck. The span in time between first and subsequent injector failures on each truck is likely due to manufacturing tolerances with the injectors. (Assuming injector failure is due to particle wear).

Coincidence? Who knows. But I feel its a point worth mentioning. I feel this particular case supports what George M has been preaching.


A few things to keep in mind;

everything eventually fails,

the injectors can fail by other means (other than just particle wear) or in other modes (like you experienced first hand).

Only the reliability and FI engineers at GM/Isuzu/Bosch have the data and know for sure. And they are not likely to share this info with us.

What we need to know from HD90Rider is if he uses the supplemental filtering, what type of filter he uses and when he started to use it.


Sorry for the long rambling,
Alan

[ 01-13-2004, 04:41 PM: Message edited by: OC_DMAX ]

[Cliffee]

If anyone plans on keeping their truck for a long time I would definately add some sort of better fuel filtering and using as fuel additive to put in some extra lubricity seems like an awfull cheap good insurance.
I installed he 2 micron Racor Pre/OEM and I use the Stanadyne additive. So far I have 7k on the Racor and no problems at all!

[Viking]

I believe the engineers/bean counters have the data and they feel the injectors should just make it by the 100K mark,as truck one did,using only the OEM filter.

[GT]

I just had all the injectors and pressure reg. replaced. My truck had 49,000 miles and been smoking and a rough idle for about 1500 miles when I took it in to the dealer. It had 4 bad injectors. I have the mega filter installed post oem but only installed it about 1000 miles before the problems started My dealership is a great company and there was never any question about replacing all of the injectors and I told them about the extra filter.I had a long talk with the service manager and he said GM is aware of the problem and is replacing the old fuel filters with new ones that will filter down to a smaller micron. He also said Ford and Dodge were having the same problems with their hi pressure rail systems and at this time no fix is available.My truck was delivered on 11/00 and is used to pull a 12,000 lb 5th wheel. It has had a 40 hp chip on for 40,000 miles, the fuel filter was changed every 10,000 miles.I have used power service in the fuel and filled up at high use stations. I don't know what made my injectors go out this soon but I think that the box may have had some thing to do with it as the stock trucks seem to getmore miles before the have problems. :confused:

[Cliffee]

GT,

I believe GM started using a better, improved injector somewhere in the 2002 models.

[hd90rider]

Hey All, Sorry it has taken so long to reply, but I have been on the road. 1st, I do have an additional filter on the big tank, w/water separator, which I check often & I NEVER use cheap fuel. Always name brand "Flying J" If not available, I get the next name brand I can get to. However, as I sit here writing this post,I am in a motel in Tx. awaiting a new engine. At 282K it went to ****. Fuel in the oil again ( (4th time), & finally quit running. I expect problems at high mileages, but not a complete failure. All major problems I have had,have been "fuel related". Injectors, pump, return lines coming loose,cup seals leaking around the injectors. This is the worst it has ever dumped fuel in the oil. Drained the crankcase twice,(4 gallons of diluted oil each time & put in new oil,trying to get to help. Didnt make it!! Towed in,now here I sit,waiting to give GM another $12,000 approx. to get back to work. Without using all the power upgrades, I felt this engine should last longer, like the other brands. Yes they have problems,but they are still running at 400k to 700k. The engines were fixed. Since I passed 215k It has been downhill,with a garage call about every 2 months. Hopefully the LLY will fix these fuel related problems ( get that crap out of the valve covers). Oh well, vented now , Any one have $12k they dont need?? :(

[Runaway]

Bill, sorry to hear about your breakdown, used to drive truck in my early years so I know when the wheels aren't turning, your not making any money!
282K is more miles than the average joe will ever put on their rig especially when most are trading every two years or so. Hope all works out for you.

[hd90rider]

Thanx Runaway, However this truck should last longer than that. Others, driving Fords & Dodges, I work with have twice those miles. Yes they have had breakdowns, but not to the tune of a whole new engine due to fuel being put in it 4
times. Chevy better get on the stick or they will never become a threat to Ford & Truck as a reliable work truck. I thought when the D/M came out "O BOY FINALLY" guess it still hasnt happened. Whats worse,I feel GM knew after the 01's there were fuel system related problems , but took 3 yrs to correct it& let the customers pay the piper. :mad:

[Heartbeat Hauler]

I talked to my service manager yesterday to ask about adding a second fuel filter and he had no problem with it, especially after I told him about injector failures. He relayed a story that while he had only one failure to date, it was a pretty bad one. Apparently a guy from 'Bama was driving through Evansville and he heard some kinda noise in the engine so he shut his truck off. One of the injectors kept running and the cylinder filled with fuel. When he tried to restart the truck, all the bad stuff happened. I felt for the guy (from Bama)but only one failure is kinda comforting....right? :(
JP

[j ray koster]

In refrence to after mkt injectors being available, what is (soon) and where? does anyone know where I can send 8 injectors for cleaning?