Injector Noise

[Diesels Forever]

I have owned diesels for a long time; 6.2, 6.5, 5.9, several duramaxs even old birds like the mighty 5.7 Olds and toroflow. The one I'm having problems with now is a 2001 2500HD owned since new. It has and obvious injector noise that is not the pilot injection turning off. It sounds like a single injector "hammering" and is most audible when the engine is warm and under load at rpms between 1700 and 2500. It is a distinct noise that will drive you nuts any time you cruise the highways, but especially when pulling.
The service work to date; at 30,000 a high pressure line "blew off" wile driving, this line is located on the drivers side of the valley between the intake and valve cover, my dealership simply bolted it back together in an hours time and sent me on my way, at 38,000 they put a new pump on to solve a surge at idle problem. Since the pump replacement I've had this noise but it

[More Power]

Uncooperative dealers are not a lot of fun, but I would ask that a tech go for a ride with you. He can selectively disable one injector at a time using a Tech II scan tool. This should help to isolate a faulty injector. I'd also ask him to perform a cylinder balance test, and check the desired and actual rail pressures.

Somewhere in this series of tests you'll find the problem, if one exists.

MP

[dmaxalliTech]

Originally posted by Diesels Forever:
The diesel mechanic at my local dealership said he can hear the noise but won't chase it because he claims "GM isn't going to throw money at a noise, it's a diesel". He also said the injectors are so sensitive that ANY problem would set a code and there are none.
Sounds like the real reason is that he cant fix it.. I dont agree with the code thing either.. A misfireing injector wont set a code until its balance rate goes above 15mm. There are other codes for injectors also but they dont always set. I have seen more with out codes then with.

[Bigwheel]

My 02, had an Injector that was out-of-balanced, not sure if it was really fixed, but when I floor the pedal, she takes off, and shifts through a few shifts, getting to about 60 mph, then the rpm's get into the 3k area, I get a wierd rattle and some smoke, not sure if same as yours but very wierd, and noticable.....

[Bigwheel]

MOREPOWER / Dmaxallitech
I brought my 02 DMAX in the shop for a possible injector issue, when I floor the pedal, I get over a second or two hesitation, then it takes off, I get some smoke after 60+ MPH, this was the report I was given after getting my truck back.." Owner states MPG is dropping, states truck hesitates, engine getting louder overtime, Scanned - no codes found, checked fuel restriction, ok, ran fuel pressure test, passes, RD test- power normal, No unusal noises heard, scanned data showes cylinder#7 out of balance ( 6.3mm spec is 4.00mm at 35 mph Idle, 5.5mm at 60mph, no unusual scan data, test drove truck 33 miles, oil level acceptable, injector ok, shimmed app for better throttle feel"
This was end of August, been driving it, same probs still exits, any suggests???, I have talked with Dmaxallitech, and maybe planning on visiting him
I have had to change dealers to try to get this resolved, I believe their trying their best, just looking for your input and opinion. Thanks!.

[dmaxalliTech]

Originally posted by Bigwheel:
I have talked with Dmaxallitech, and maybe planning on visiting him
I have had to change dealers to try to get this resolvedMay I suggest one more change of dealer? :D

[Bigwheel]

dmaxallitech
It's a lonnng drive to your neck of the woods, but I'm sure totally worth the drive, if injectors are available, how long to do the work, and so on, I will e-mail you, thanks!.

[Diesels Forever]

Thanks for the help guys I'll try to get the dealer to do some of the test you sugested.

[More Power]

If your truck is outside the 3/36 warranty, you'll have to pay a $100 deduct anyway, so I'd suggest visiting the dealer, explain the problem to the service writer, then request to "buy" an hour of their tech's time. Don't even talk about the warranty at this point.

Then have the tech go for a ride with you, and run the tests outlined in my earlier message. You're paying for his time, and he will (should) do what you ask (he is now working for you).

Then, if an injector or fuel system component can be demonstrated to be out of spec (based on the tests performed), the replacement will (should) be on GM's dime. Be tactful... Write everything down for later reference.

On the other hand, if anyone here is new to diesels and aren't familiar with the changing diesel engine sounds (with cooler ambient temps and/or changing fuel quality), and no defective component is found, you'll gain a little peace of mind knowing that your engine and fuel system are OK, and the sounds produced are just a variation of normal.

MP

[Kennedy]

Big Wheel,

If the drive over to see Eric is a bit much, Snell Motors in Mankato has seemingly good relationship with their Dmax customers. I recently had a customer order some "goodies" through them. I guess what I'm trying to say is at least they seem open minded!

[ 10-29-2003, 05:01 AM: Message edited by: kennedy ]

[Diesels Forever]

Just an update for anybody who cares.

A friend of mine, who happens to own his own shop and is master certified, put it on his scanner and said it had a p0205 code and a p12** code that I don't remember, and was reading -512 mm3 (whatever that means) on cyl 5 bal. test but was intermittant. He said it did it when he first looked at it so he cleared the codes and tried again and couldn't get it repeat. He also told me that he could feel a "dead miss" at 1400rpms.

I told my dealer and they're supposed to look at it next tues. They did tell me if there was no code while it was in there there was nothing they could do. Wish me luck guys, I'm going in.

[midwest]

This is once again a simple diagnosis. If you have a knock or hammer,each injector can be disabled indiviually As previously stated. Some knock issues Are hard to narrow down and require a liitle creative work.If a fuel knock is suspected and can't be narrowed down, you can exaggerate the noise in output tests with the TECH II and run up fuel pressure. This can be run up to 160 KPA and with a little feathering of the throttle a leaking injector will rattle a few seconds after you back off the throttle.(read as--more fuel leaking past nozzel on decel)
With the fuel pressure @ 160 KPA look at the ballance rate At idle. My experience usually finds that the noisy injector is VERRY negative.
The injector pulse on the noisy injector also dances around alot and will actually drop to ZERO for a split second.

These are a few of my suggestions and are SUPLEMENTAL to normal fuel diagnosis, (balance rate, fuel return rate,Actual and commanded fuel rail pressure)
Hope this helps but if you don't have a TECH II it probably won't do much good.There are a lot of shops out there with poor diagnostic skills just keep searching till you find a good one.Some of us do care.

[midwest]

Keep us informed on you appointment tomorrow.
Hopefully they give a rats A-- about the customer. Midwest

[Diesels Forever]

Well, here we go. I needed a day to cool off after a shouting match with the dealership that my business and family used to buy over $100,000 worth of vehiciles a year.
I schedule my truck for a tranny fluid change, front and rear diff service, and misc test that I will explain in a minuite. I drop my truck off at 7:45 the day I was supposed to and leave the service rep with the instructions to do the above service work and perform a cylinder balance test, check the desired and actual fuel rail pressures, and I attached a printout of midwest's post as well as my post with the code/dead miss information to aid in discovering if the #5 injector is going bad because I had a injector noise now between 1800-2500 when hot.
I call that night at 5:00 to see how they were coming. The service rep. said the diesel tech (a different one than I was dealing with earlier) test drove my truck and did not hear anything other than diesel noise and that was all the farther they had got. At this point they hadn't checked it for codes. He said they needed to keep the truck overnight. I remained calm and said I really didn't want anybody driving my truck around I just wanted the work that I requested on the service order done. I also asked why it was taking longer than a day to perform this work, I got the run-around.
Day 2
I recieve no word on my truck. I call at 5:15 for an update, mechanic gone have to wait until tomarrow. .......OK...... Whatever.
Day 3
I call at 8 A.M. Your fluid was changed truck is ready. I ask if they found anything wrong with the injectors. Long uncomfortable pause. Rep said, "Checked for ticking noise in engine at 1800-2400 rpms when hot, possible injector. Scanner checked no codes, test drove OK." I became upset but not irate. I explaned that when I dropped it off I just wanted tests run and fluid changed, and didn't understand why that was not done. After a few minuits of questions he said "let me talk to the mechanic." ......hold....
Oh yea, mechanic said balance rate ok at idle, and the uhhh rail pressure was good. This was BS. You could tell by his voice. I get the total for what they had done and went to get my truck.
When I get there I go out and start my truck and rev it up to 1400, obvious miss, truck shaking. I go back in and get rep. He comes out, rev up to 1400, miss & shake. He says No Code, No Problem. At this point I loose it. We argue about whether or not a engine is malfunctioning regardless of it setting a code for about 15 min. He claims that if my truck does not set a code that it is ok, and unless it specifically says the #5 injector is bad period, they're hands are tied. I pay my bill, and do a burnout out of the service drive. :mad: I was MAD! :mad:

I want soo bad to have someone else look at it and fix it so I can go back to tell them there was a problem and that they are losers... or somthing to that effect.

[midwest]

Sorry about your problems. The way I see it, you could take one day to drive to IL and I'll fix it the second day and the third day you could drive home happy. :D I'm really tired of these dealers trying to blow flowers up your a--!The assumption that the customer can't tell if their vehicle sounds or drives different than before is ridiculous.If you have no fricken clue, then addmit it and send them on their way. These are great engines but do have some problems that are easily repaired.Keep the faith and maybe its time to call chev and ask for the area service manager to recomend a different shop.

[LakeDaisy]

Can anyone suggest a dealership (that has a good duramax mechanic) in the Central Florida (Tampa/Orlando area). Thanks.

[midwest]

Hey diesels forever, did you get your truck fixed yet. Keep us informed.

[Diesels Forever]

New Info For Today.
It's amazing what a call to the owner of the dealership will do. The diesel tech and the service manager went for a ride with me this morning, diesel tech heard noise (louder now), service manager heard it too. Both guys said there is no way to kill a hole with the tech-2 while your driving it so there is no way of knowing wich injector, if thats what it is, was making the noise. They said you can only do it at idle. I know what I saw on my friends scan tool and I am 99% sure the #5 injector is taking a dump. We talked about replacing it (#5 injector) and what they said was if there were no codes in it at their shop, they were almost positive GM was going to want the injector back for testing. Anyway they say it's a 6hr job to change an injector and they are starting on it today.
Basically if the injector noise goes away the dealer will do all they can to push it through warranty, if not I just bought a $500 injector, and some pricey shop time.
The dealer is now "taking me at my word" I guess, so I have some restored faith. I know this will fix my noise and it will be all better in a couple days. Maybee I'll get back some of the mileage I lost when they put the new pump on! smile.gif

[Diesels Forever]

Final post!!

Got my truck back Friday night, I drove it about 15 min. no noise. Drove all day saturday, never shut it off from 8 A.M. to 10 P.M. :D NO NOISE!! :D

It's a happy day! Well, except for the huge orange zip ties the dealer put on my engine plugs so I can't plug in a chip. I guess they got the last laugh smile.gif Oh well, it runs better now anyway.

[WillowCreekStable]

ZIP TIES??????

Is this now SOP at dealerships????

[Diesels Forever]

Yup, zip-ties. They didn't put anything on the OBDII port in the cab though. I guess some upgrades are ok and some aren't. smile.gif I should have bought a Quad. ;)

[OC_DMAX]

Either that or find a source for huge orange zip ties! smile.gif

[Rockin]

It is not hard to take a knife and open the zip ties. There is a little tab that ratchets into the band, all you have to do is pull it back and the tie will slide open. You just pull it tight when you need it in place.

[Diesels Forever]

They pullled them tight and cut them off flush, if I release them I'll never get them back together again. I'll just have to find some replacements, and take a good picture of how they were, so I can put them back!
:( It's sad that I even have to think about stuff like that, It's not like GM, or the dealer is losing any money, we buy 2 or 3 new vehicles from GM every year. :(

[midwest]

I'm sure the cable ties you describe are the ones that come with some gm parts holding the tags. I probably have a few hundred I have saved over the years. Injector pulse width and injector timing will never cause an injector failure. Fuel pressure could.Once again ignorant shops just being ****y.

[Dr_Crane]

Thanks again to the diesel page. My truck doing the same thing stopped at dealer, had it scanned, no codes found! I didn't want to press the issue until I knew what the problem was so I could explain to them how to fix it AGAIN! Guess I wasn't using the right search words. Was just on the phone with GM cust assistance last night discussing my previous issues (my long letter accompanying the survey got their attention) and I brought up this noise issue and my reluctance to have the dealer look at it. The rep put me on hold, called my dealer, and said don't worry it will be taken care of! Can't say GM isn't trying...this next fix will put me well over the $10,000 mark in warranty work in 48000 miles!

[J54 Mark]

"they say it's a 6hr job to change an injector and they are starting on it today.
Basically if the injector noise goes away the dealer will do all they can to push it through warranty, if not I just bought a $500 injector"

WHOA!! Hold on there! Six hours to change an injector? $500 to replace one? Can this be right? I'm supposed to sign up for my new truck in a couple of days - should I cancel now and get while the getting is good?

Mark