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GM Tech (Cam)
GM Tech (Cam), Chevy Technician
Category: Chevy
Satisfied Customers: 29427
Experience:  GM Grand Master Technician 2007. 14 years experience.
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, just changed injectors on a 2002 Silverado duramax

Customer Question

JA: Thanks. Can you give me any more details about your issue?
Customer: just changed injectors on a 2002 Silverado duramax that was getting fuel In the crankcase. Engine started right up and runs nice at an idle. at about a 1000 rpms it seems to develop a miss. take it out on the road and it wont hardly pull itself and the white smoke pours oujt the exhaust
JA: OK got it. Last thing — Chevy Mechanics generally expect a deposit of about $18 to help with your type of question (you only pay if satisfied). Now I'm going to take you to a page to place a secure deposit with JustAnswer. Don't worry, this chat is saved. After that, we will finish helping you.
Submitted: 10 months ago.
Category: Chevy
Customer: replied 10 months ago.
scan shows no codes
Customer: replied 10 months ago.
It ran just fine before we changed the injectors. Other than the fuel getting in the crankcase. Good news is, we seem to have the fuel In the crankcase issue solved.
Customer: replied 10 months ago.
Posted by JustAnswer at customer's request) Hello. I would like to request the following Expert Service(s) from you: Live Phone Call. Let me know if you need more information, or send me the service offer(s) so we can proceed.
Expert:  GM Tech (Cam) replied 10 months ago.

Hi there. I am Cam. Is it losing coolant now?

Customer: replied 10 months ago.
no
Customer: replied 10 months ago.
we did drain the system down when we changed the injectors
Expert:  GM Tech (Cam) replied 10 months ago.

OK, but my concern is that you're losing coolant now. On your engine, the injectors have a removable sleeves that is supposed to stay in the head. Sometimes it may be allowing coolant into the cylinder. If the white coolant, and one of those sleeves has pulled out and it leaking.

The other concern lies with the cleanliness of the injector line. The long injector not to go to the valve cover is bad for trapping dirt and on the backside. If those were not cleaned out thoroughly prior to installation, some dirt falling into the injector and causing the injectors stick open when it shouldn't be

Customer: replied 10 months ago.
none of the sleeves moved and the injection lines are new
Customer: replied 10 months ago.
doesn't have the white smoke idling. just when you get out on the road. under load. heavy blue smoke In shop
Customer: replied 10 months ago.
wont go over about 25 mph on road
Expert:  GM Tech (Cam) replied 10 months ago.

Do you do you have a scanner that can read and control the fuel pressure?

Where did you source be injectors from?

Customer: replied 10 months ago.
as for losing coolant can really say for sure. haven't really run it enough to know. but I can 't hardly believe we are. I really watched for the sleeve movement because I k new it was known to happen. As for the scanner I don't have . but I have a friend that probably does. Injectors L&J Diesel Jacksonville,FL
Customer: replied 10 months ago.
Remanufactured with new nozzels
Customer: replied 10 months ago.
Dieselogic
Customer: replied 10 months ago.
when we get out on the road with it, it shakes like a dog having a seizure.
Expert:  GM Tech (Cam) replied 10 months ago.

Ok, sorry for the delay, I would think that one of the injectors may have an issue. The scanner will be vital for this.

Customer: replied 10 months ago.
ok . how do I check it
Expert:  GM Tech (Cam) replied 10 months ago.

With the scanner we need to first check balancing rates. +4 to -4 in park when hot and +6 to -6 in drive stopped.

Then do the return test.
Find the 2 fuel lines on the rear drivers side valve cover. Take the smaller one off and attach your hose to the metal pipe coming from the engine. Put the other end into the container and run the engine to fill that line. Then shut it off and remove the IGN 1 relay from beside the starter relay. empty out the container and keep the line full. Crank the engine for 15 seconds fully and measure the amount of fuel that comes out of that line. More than 24cc means the injectors are still returning too much fuel and causing this.

Customer: replied 10 months ago.
My scanner wont do the balance checks. I have to locate one that will.
Expert:  GM Tech (Cam) replied 10 months ago.

Ok, sounds good.

Customer: replied 10 months ago.
messed with it a little last night. At an idle it really doesn't smoke. Run it up to about 2000 RPM and it smokes so bad it will run you out of the shop. I will get you some balance rates this afternoon.
Customer: replied 10 months ago.
Balance rates (1) Park 0.6 Drive -4.1 (2) P 1.3 D -6.6 (3) P -5.0 D -6.1 (4) P 1.1 D 1.8 (5) P 2.9 D 7.0 (6) P 1.4 D 0.4
(7) P -0.5 D -0.2 (8) P 0.6 D -.9 Really smokes when put it in Drive to check balance rates. Doesn't in Park.
Expert:  GM Tech (Cam) replied 10 months ago.

Needs to have #2, #3, for sure replaced and #1 is close. Spec is +/- 4 in park when hot and +/-6 in drive. 2 is front drivers side. 1 and 3 are first 2 on passengers side.

Expert:  GM Tech (Cam) replied 10 months ago.

- numbers mean the system is trying to take fuel away, like the cylinder is getting to much. After idle in drive, the balancing rates stop so those cylinder will be getting too much fuel and will smoke.

Customer: replied 10 months ago.
Was over messing with truck again. Did another balance rate check (1) P .0 D 0.5 (2) P .0 D -0.7 (3) P -1.1 D -2.5
(4) P -0.4 D -1.7 (5) P 1.3 D 5.3 (6) P -0.7 D -2.1 (7) P 0.2 D 0.5 (8) P 0.6 D 0.8
Why are they so much different than the first time when I check them? I'm getting totally confused.
Expert:  GM Tech (Cam) replied 10 months ago.

Was it as warm as before?
When running, do they change a lot?

Customer: replied 10 months ago.
it was warmer the second time
Expert:  GM Tech (Cam) replied 10 months ago.

Its still an issue that those changed. Go for a drive, get it hot and try one more time.

Customer: replied 10 months ago.
it runs so poorly I wouldn't want to take it down the road.
Customer: replied 10 months ago.
Was going to go over and do a return line test
Expert:  GM Tech (Cam) replied 10 months ago.

that is my next suggestion.

Customer: replied 10 months ago.
15 sec. about 75cc
Expert:  GM Tech (Cam) replied 10 months ago.

I hope you have warranty on those because that is about 3 times the allowable.

Customer: replied 10 months ago.
They are. Going to contact them tomorrow.
Expert:  GM Tech (Cam) replied 10 months ago.

Sounds good.

Customer: replied 10 months ago.
Did a compression check between 350 & 360 PSI on all holes.Going to do another balance check tonight
Expert:  GM Tech (Cam) replied 10 months ago.

Ok, sounds good. I am still thinking injectors are bad. Why they are different rates is odd.

Customer: replied 10 months ago.
Might be that the guy doing the diagnostics don't really know what he is doing. Going to have a friend bring his scanner over tonight and do balance rates and what not for me. We'll see what he comes up with and I will let you know. Thanks for everything so far..
Expert:  GM Tech (Cam) replied 10 months ago.

My pleasure.

Customer: replied 9 months ago.
Did a fuel pressure check. Actual was right with the desired. Pulled injectors out of right bank and sent them back. Let let you know when I find out something. Thanks
Expert:  GM Tech (Cam) replied 9 months ago.

Ok.

Customer: replied 9 months ago.
Ok, I'm back. #3 was borderline as for being in tolerance. So they had us send the Left bank back. #2 was dumping fuel and #4 was far enough out of speck that there tech I talked to rejected it. Now they tell me that they have put there best guy on it and that he don't make mistakes. Well, my feeling is that if the rest of them are known to make mistakes they had better go down the road. This is a hell of a screw up at my expense. So now i'm just waiting to here back from them as to when they are going to get sent back to me.

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