codes P069e followed by p2635 on zl1 going down the track?

[Mil]

Anyone have any ideas or have had this before tracking your zl1 at the drag strip.

I've been drag racing this thing since last yr with out any issues til now.

I had cleared the code initially when it first occurred going down the track; but the codes came back and is tripped only from making a few passes down the qt mile.

Under hard driving road conditions they don't get tripped.??

_ Mil

[etmx183]

http://www.camaro5.com/forums/showth...ighlight=p069e

[ZO6 Bryan]

What mods have you made? It sounds like your fuel pressure is dropping during a dragstrip run. At high load the FPCM commands 65 psi fuel pressure. If the actual pressure is less than commanded it will set those codes.

[Mil]

Originally Posted by ZO6 Bryan

What mods have you made? It sounds like your fuel pressure is dropping during a dragstrip run. At high load the FPCM commands 65 psi fuel pressure. If the actual pressure is less than commanded it will set those codes.

only mod on it is a rotofab
CAI.. stock factory tune.

[Mil]

Originally Posted by Mil

only mod on it is a rotofab
CAI.. stock factory tune.

I must be the only poor soul in this forum with this issue? I took the Z in to the dealership at Rockmont Ourisman and came away with nothing but no confidence what so ever that they even attempted a thorough diagnostics of the fuel system to determine why the (FPCM) Fuel pump control module sent a P069E command to the ECU to trip the MIL/check engine light. When the MIL tripped making my pass down the track at Capital raceway i felt a surge or loss of power half way down the track with my foot all the way down to the floor holding at 100% full open throttle. The secondary code that explained why FPCM sent a P069E command was code P2635 - Fuel Pump 'A' Low Flow/Performance?????

Which leaves me to feel that I may be dealing with a possible failing fuel pump. But the kick in the head is these codes had occurred twice only at the track on two separate occasions and it had no effect on the drivability of the car; its still currently running strong driving around on the highway, and locally. The first instance the codes were cleared with an OBDii scanner. The second occurrence i drove it til the MIL sort it self out.

I want to keep this thread alive for hope of anyone who knows a friend with a similar issue who owns a ZL1 or CTS-v who's not tuned and only has a CAI that may know something and which dealership in Maryland properly put in the time and effort and have resolved the issue. My ZL1 power train warranty is due to expire this yr August 2015; so if there is any GM representative looking at this can shout out to Rockmount Ourisman in Rockville MD to do the right thing do your job and help create promoters, and not detractors... that would be appreciated.


Thanks Mil

[slickmetal]

only time I felt what you did was when my old '11 SS was modified and tuned and I didn't turn all my traction control off. Yes, so full throttle and when it was going to shift it felt like it died, then BAM full throttle. Figured the car was cutting fuel because it sensed there would be a traction issue at full throttle. Never happened again when I did the full disable...Only thing is, the car never threw or kept a code.

[wirebender]

sounds like a weak fuel pump....I had to have mine changed for being "weak" after cam...new pump does fine....although I am maxed out on it!

[ZL1 TIBS]

This happened to me at the dragstrip last time also. When it threw the code, my car backfired. It happened on the burnout and then once during the run. the car ran a normal time so I wasn't too concerned. A guy at the track with a scanner read the code and we cleared it and it hasn't come back since. I attributed it to having low fuel level and uncovering the pump inlet. Doesn't make 100% sense though because you would think it would get worse as the night went on. I actually ran my best pass ever after this happened.

[ZO6 Bryan]

True about the gas tank level. Were you low? But the solution will be to scan the ECM when it happens. Like a hard drag pass. And watch fuel pressure on the scan tool. See if it is dropping at WOT.
And what brand CAI did you put on. If you put on a CAI and didn't tune it you fuel trims may be way out of whack. And that might result in a lean condition when pushed hard on the drag strip.

[Mil]

Originally Posted by ZO6 Bryan

True about the gas tank level. Were you low? But the solution will be to scan the ECM when it happens. Like a hard drag pass. And watch fuel pressure on the scan tool. See if it is dropping at WOT.
And what brand CAI did you put on. If you put on a CAI and didn't tune it you fuel trims may be way out of whack. And that might result in a lean condition when pushed hard on the drag strip.

Wow now i feel bad..LOL interesting to see a few of y'all mention the same thing that Ourisman was implying about having low fuel. But I'm sure i were 3/4 of tank full at least well over a half tank of fuel on the two occasions these engine codes tripped going down the track. My first pull is good after a long drive to the track. The codes tripped on my 2nd run. And yes I do have a ROTO FAB CAI installed without a tune. What is WOT?

[Mil]

Originally Posted by ZL1 TIBS

This happened to me at the dragstrip last time also. When it threw the code, my car backfired. It happened on the burnout and then once during the run. the car ran a normal time so I wasn't too concerned. A guy at the track with a scanner read the code and we cleared it and it hasn't come back since. I attributed it to having low fuel level and uncovering the pump inlet. Doesn't make 100% sense though because you would think it would get worse as the night went on. I actually ran my best pass ever after this happened.

what is the pump inlet? did you mean you forgot to put your fuel cap back on and ran your car down the track?

[Candr3535]

Wot= wide open throttle

[mmarx82]

Had the same happen to my at one of my HPDE events, cleared it while still at the track with my Bluetooth OBDII scanner that I was using to datalog with. It never came back and I had a relatively full tank btw.

[Mil]

Well folks I'm gonna share a good read to help my fellow ZL1 owners that may run into the same engines codes i'm dealing with currently. This write up sheds some light in understanding how our fuel system operate to maintain proper fuel pressure for the injectors.

http://injectordynamics.com/articles...ure-explained/

the last few paragraphs confirmed something that i caught that Ourisman may have overlooked; when at WOT the fuel pressure should be higher than when at idle? Could anyone chime in to confirm this fact in comparison with your own ZL1.. ???

My scan tool saved a freeze data from the ECM of what was going on when the check engine lights P069E and P2635 event occurred. At Throttle command 100% (WOT), my fuel pressure KPAG reading was at 312; when i monitored the system with my OBDii scanner while the car is idling the Throttle is about 9.5% with fuel pressure KPAG 349. I would think at 100% WOT fuel pressure KPAG would be higher than when at idle?