Error Code P1175

[snaward]

Final update - I got the car back today. The dealer did cover all the repairs under warranty, even a broken brake switch, and providing a loaner for the 2 wks it was in the shop - so they did good on their part.

The final repair involved taking the passenger side head off, sending it to a machine shop to resurface the valve seat and valve. They had tested the valve seating issue by first shimming the valve spring to increase the valve pressure.

So now the passenger side head looks nice and clean.

Question - anyone else see this on these 6.2L engines with 93K miles? I have not found much discussion on this model GMC searching google.

BTW - I did learn a new trick for working on these vehicles, take the front tires off and drop the front end down to make it easier to work on.

 

[Ryann]

I'm bumping this thread back to the top because I have the same code for my 09 Denali. I have a hard time accepting that it may be the passenger cylinder head. Has anyone else encountered this code and fixed it. I've tried several different in-tank solutions for injector cleaning with no success.

 

[Ryann]

bump

 

[Adam Rollo]

bump

What luck, I'm having the same issue with my 08 Denali 92k miles.

I ran a can of seafoam through the gas tank, drove until the low fuel light came on. I put another can in with the highest octane at a Chevron. The CIL went off after about 30 miles. I about did a backflip.

Then it came back on 50 miles later. now I'm on the forum. Anybody have any luck with a permanent solution besides machining the valve and valve head?

I'm suspecting an electrical issue of some type, maybe just coincidence but both times the CIL came on was after a really torrential rain that is not the norm for this vehicles home.

thanks

 

[Ryann]

Adam, Please reply here if you happen to come solve this issue differently than the suggestions already given.

 

[Ponchonutty]

Bumping this thread. Anyone else have this issue? Give a little back story. First my rig is now in the 200k mile club. Been doing OK but I feel that I will need to replace the oil pump soon (or engine) because when it got severely cold around here, I would have no oil pressure until the rpms went up. Once warm, I averaged a little less than 40psi driving about about 18psi at idle. Before Christmas I got the P1175 code, reset it, and ran seafoam through it along with Amsoil gas treatment. Light has been off until today. I drove about an hour at 80mph and started hearing a slight ticking noise on passenger side. Got to my destination and all was fine. few hours later took back off and the ticking was louder. Checked all fluids and all was fine. Continued on my drive but backed speed to 65. Seemed to quite down and made it home. That's when I read the code.

About 6 weeks ago I had an issue where the #3 spark plug blew the porcelain out. The plugs were only about a year old (AC Delco) but went ahead and replaced all of them again. #6 plug was sort of black and crusty. It definitely isn't firing correctly. At first I thought maybe an injector issue but now I am wondering if I have a valve issue???? Anyone have any ideas???? Odd that it quieted back down and drove fine another hour back home.

 

[CadillacJoe]

Hi folks,

I just joined his forum after search and reading pretty much every issue related to code p1175. I have a 2008 Escalade that has been having this issue. I am fairly good with cars, I replaced the plugs, wires, coils, injectors and cleaned the mass air flow and throttle. The Escalade idled much better but I still kept getting the code. A lot of pages reccommend injectors, however new ones did not help. I them replaced both upstream 02 sensors and the issue went away temporarily. Just a note, I would only recommend ACDelco parts, I put some cheap 02 sensors first and they were no good, same thing with coils on a 2007 cts. I am still getting the p1175. I have a torque app that lets me check the fuel trims, and misfires. I get a misfire on cylinder 4 and once in a while on cylinder 2. Its not misfiring bad, just a few misfires every driving cycle, not enough to trigger a specific misfire code for a particular cylinder. I checked the plug, gap, and swapped the wire. I also did a smoke test to check for vacuum and intake leaks, none found. The strange thing is my fuel trims look fine, and also I don't seem to get the code while its hot outside, only during night time driving. The Escalade got 21 MPG on a long trip and idles great. Called Cadillac and they were surprised I did most of the basics.

 

[Ponchonutty]

Mine I believe was due to low oil pressure. Once I changed the oil pump o ring and ran some stiction reducer along with seafoaming the engine, the CEL went away.

 

[Doubeleive]

Hi folks,

I just joined his forum after search and reading pretty much every issue related to code p1175. I have a 2008 Escalade that has been having this issue. I am fairly good with cars, I replaced the plugs, wires, coils, injectors and cleaned the mass air flow and throttle. The Escalade idled much better but I still kept getting the code. A lot of pages reccommend injectors, however new ones did not help. I them replaced both upstream 02 sensors and the issue went away temporarily. Just a note, I would only recommend ACDelco parts, I put some cheap 02 sensors first and they were no good, same thing with coils on a 2007 cts. I am still getting the p1175. I have a torque app that lets me check the fuel trims, and misfires. I get a misfire on cylinder 4 and once in a while on cylinder 2. Its not misfiring bad, just a few misfires every driving cycle, not enough to trigger a specific misfire code for a particular cylinder. I checked the plug, gap, and swapped the wire. I also did a smoke test to check for vacuum and intake leaks, none found. The strange thing is my fuel trims look fine, and also I don't seem to get the code while its hot outside, only during night time driving. The Escalade got 21 MPG on a long trip and idles great. Called Cadillac and they were surprised I did most of the basics.

I would suspect a electrical issue connector or broken wire possibly in the injector harness, heat makes things expand (therefore making connection) and cold makes them contract (loosing the connection) just an idea based on "it works fine when hot"

 

[Kraig]

Do these engines have AFM? If so, #6 is an AFM cylinder and it could be the valves are gunking up as a result. I had the passenger head off my 5.3 for AFM issues (#4) and I could stick my finger into the intake port and there was sticky oily gunk collected on the short side of the runner just inside the intake valve. Taking the head off and doing a quick valve job would clean that gunk out and restore the valve/seat