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EGR Valve

Unit453

Unit453

Cruises comfortably at 140...
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I'm getting EGR codes. Been getting them all day. It just so happens that I loaded the Hyperpac tune in today as well. It runs fine but not sure why the code keeps popping up after I clear it. And no, its not blocked. Its bone stock.

Are there recalls for this that anyone knows about?
 
Well I would unload the Hyper pac and see if that stops the codes. I'm surprised you didn't finger stick it. Mine is Fingerd with Blocker plate and it passed emissions in NY. I'm waiting to see if it passes the sniff test w/o the cat now. Went in last week to test but the machine took a dump and I'm waiting on parts till it's up and running.
 
I had a bitch of a time getting my 04 inspected with my 4" turbo back and no cat. Where I was at, they wouldnt even look at it if the cat wasnt there...

I thought about detuning but its gonna have to wait for the weekend.
 
There have been EGR problems on LBZ engines that required replacement of the EGR valve and/or EGR valve motor and there are some TSBs about it, but I don't have access to them. Maybe one of the GM techs can check them out for you. I've been lucky so far, with 29,300 miles no EGR problems.

You may want to remove the Hypertec and see if the codes don't return. If you have to take it in, you'll need to remove the tuner anyways.

If the codes come back, leave the codes in (don't clear them) when you take it in to the dealer, or they will just send you away. At least around here the dealers won't touch it if they can't see the codes for themselves.
 
Good luck man. I was lucky, when i straight piped mine / blocked the EGR i never got a code before i fingerstuck it. Now my PPE gets rid of the code.
 
Yeah, some trucks get them and some dont. I have the cat on still so I didnt think it would be a problem. I'm kinda thinking that its the Hypertech causing it for some reason.
 
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My LBZ is all stock but the EGR went bad at around 19842 miles. Trying to think of what code I was getting when it started acting up. Appears that the LBZ is having some EGR issues. Took the truck to the dealer and they replaced it under warranty. Wondering how long this one will last and will it be covered after my warranty goes out in December 2008.
Sorry I couldn't help anymore than that.
 
Thanks. Thats what I was looking for. I thought I heard of people with EGR problems but I wasnt sure.
 
I'm pushing 49K now with no EGR troubles and the original valve, or should I say no EGR related codes (knock on wood). About 20K ago, I had a re-flash done that addressed smoking and rough idle problems which has to do with the EGR, but I'm sure your truck has the latest calibration installed already since it's newer.

Occasionally, it would have a lopey idle after taking a long trip, shut down like if you stopped for fuel and to take care of business, and started again. The idle speed would fluxuate 50-75 rpm and the truck would rock while sitting still. Hit the gas and it smoothed right out but blew some smoke. It did this 3-4 times at the most that I can remember, and every time I was running two stroke in my fuel. Dealer tells me that the valve can stick open and cause the lopey idle without setting any codes like I experienced... even went so far as to command it open at idle with their tech ii and it ran like crap. The re-flash seemed to cure it because it hasn't happened since.
 
Thats good info....

Now you and I need to meet up this weekend for dinner or something...
 
Will do.

Also, it isnt Hypertech. It isnt the Predator either. Its stock and still throwing a code so I guess I'll have to find a dealer tomorrow...
 
Getting 2 codes now. I made an appointment at the dealership today for next week since Fridays are my only free day pretty much.

0401 and 0403. I can clear them and they both come right back within minutes.
 
Unit453 said:
Getting 2 codes now. I made an appointment at the dealership today for next week since Fridays are my only free day pretty much.

0401 and 0403. I can clear them and they both come right back within minutes.
Click to expand...

Sound like you might need a new EGR valve and/or EGR motor.

P0401 - Exhaust Gas Recirculation (EGR) Flow Insufficient

Circuit/System Description
The engine control module (ECM) tests the exhaust gas recirculation (EGR) flow when the EGR is in operation. EGR desired flow is compared to EGR actual flow. If EGR flow is lower than expected DTC P0401 will set.

  • Conditions for Setting this DTC:
    • The air flow deviation monitored by the ECM during the EGR operation indicates insufficient EGR flow for 15 seconds.
    • The ECM illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
P0403 - Exhaust Gas Recirculation (EGR) Solenoid Control Circuit

Circuit/System Description
The exhaust gas recirculation (EGR) valve is controlled by the ECM through the EGR motor high control and low control circuits. The ECM supplies voltage that is near ignition voltage to the high and low control circuits at all times. The ECM will pulse width modulate (PWM) the low control circuit to ground when EGR is desired. The lower the pulse width, the more the valve will open. The ECM will PWM the high control circuit to ground when the EGR valve is desired closed. If the ECM detects a malfunction on the control circuits, DTC P0403 will set.
  • Conditions for Setting this DTC:
    • The ECM detects an electrical malfunction on an EGR motor control circuit.
    • The above condition is present for more than 30 seconds.
    • The ECM illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
Make sure you leave the codes in, so the dealer can see them for himself, otherwise they might say "No Trouble Found" and send you on your way.

Let us know what they find.

Good Luck. :)
 
Checked out yet Nick?
I'm curious about the EGR problems and have been all along. Guess I've been real fortunate. I have 65k+ miles all stock and all original. All I ever do is once per 120 miles do a good "cleanout" about 5 miles before shutdown. Get a good puff of soot through 1, 2, & 3 then it's clean.
 
I have an appointment on friday. I'll find out then what the problem is. I have no doubt that they'll probably try and stick me with the bill.
 
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