P0430 and P2099 codes after lifter failure

LFTRTIK · November 18, 2019

Hi everyone, I’m new here. Looking for some help my truck is a 2015 Silverado 5.3 it’s been in and out of the dealership a few times in the past 2 months. The first time it was in for work I got a bad misfire it was determined that 1 of the lifters on bank 2 failed the dealer replaced all 8. I asked them if they checked the camshaft for damaged they claimed they did I picked it up. When I was driving I noticed my voltage was kind of low and I was getting smoke in the cab I checked it out myself, the tech pulled the pins out of alternator plug I also found an oil leak at the valve cover dripping onto the exhaust manifold. I brought it back in they fixed those issues. I get the truck back a day later I have the truck for less than 24 hours and I ticking noise it would get worse when it would go to 4 cylinder mode. I brought back for the third time they didn’t call me for a week and a half I call them they tell me it needs a camshaft so they didn’t inspect it when I asked, at this point I’m very frustrated! I didn’t get it back for 3 weeks they didn’t even call me to tell me the part was on backorder. They finished the truck Friday 11/15 they didn’t call me either I had to go there and check. Saturday I go to the mall with the wife and kids we drive about 15 miles and the CEL turns on! I really don’t want to bring it back to that dealer.

Today I hooked up the scanner I have 2 codes P0430 (catalyst efficiency below threshold bank 2) and P2099 (post catalyst fuel trim system too rich bank 2) same bank that the lifter failed. I cleared the codes and went for a ride same codes came back after 10 miles of driving. I monitored the 02 sensors and sensor 1 on both banks are similar in readings. Sensor 2 on bank 1 fluctuates .795v-.800v at idle, sensor 2 on bank 2 fluctuates .100v-.800v at idle. My diagnosis is bank 2 cat is bad and could be causing the other code. Also I ran it down the highway and used an infrared thermometer to check the temps on the cats bank 1 was about 350° and bank 2 about 450°. Just looking for some input and wondering if I’m going in the right direction.

Thank you in advance for your opinions.

Prem Sahadeo · May 19, 2020

~ So I have a 2015 suburban LT with 168,000 miles on the dash. it’s the first time I am doing lifter and camshaft job after the job was done I got P0430 & P2099. So after doing some diagnosing from the mechanic that rebuild the engine - we went on to service 4 new o2 sensor , Spark plugs , Wires, air filter , New MAF sensor and replace a new catalyst converter. Drive about 60 miles and the code came back switched o2 sensors thinking it’s defective because there’s a new cat that still didn’t work so I decided to take the truck to another highly recommended mechanic, he did his comparing of numbers and didn’t like how the injectors was so we decided to replace the injectors upon taking it out it was covered in oil so that was causing the fuel trim code, the other mechanic didn’t want to look at the injectors because a year ago we replaced all of them since one was giving a problem , anyways that issue with the Injectors kill the cat on one side so now I am in the process of replacing the cat and that should solve the P0430 code. We are thinking when the other mechanic did the rebuild he had oil spilled on top of the engine or something because the truck is not burning oil nor there’s no oil leak on btw the oil was on 3 out of the 4 injectors on that one side. After replacing 4 new injectors that solve the fuel trim code . P2099 Hopefully this topic help the next person who read this .

FishinDVM · May 19, 2020

Hey Prem, can you elaborate on what you think the previous mechanic did?, and why you feel the injectors had to be replaced after you only did them just 1 year ago??? I just posted a new thread and saw this... but here is my copy and text:

Ok, so 2014 GMC Sierra SLT 5.3L L83. I *HAD* a p050d, and a misfire on cylinder 8 primarily, followed by cylinder 7 also. THIS WAS BACK IN JULY LAST YEAR, 2019, at 87K. I cleaned MAF, throttle body, replaced all plugs and coils, and did a 3 part BG cleaning for carbon deposits... none of which helped that situation. Had to go in to the dealership... I was under 100K miles and under 5 years, by 3 months... they didnt care as injectors are NOT covered under powertrain. They helped me with nothing. Bite the bullet, they said 7 and 8 are bad, I had them replace all eight injectors since we are there.

SO HERE WE ARE TEN MONTHS LATER!!! All was going well, I do mobil 1 full synthetic 0w-20 every 3k, I use ONLY 93 octane, I do a Techron fuel cleaning additive around every oil change, and I never allow the vehicle to go into AFM/V4. Three days ago I get a p2099 (post cat fuel trim rich bank 2). The following day a misfire p0308 on cylinder 8. I hate the chevy dealer, so I take it to a highly recommended engine shop nearby. They did all the small stuff first, not the problem. Then they get down to it, and find the fuel injectors, especially #8 (the worst one last time, NON AFM) look like crap. Stained, corroded, carbonized... He called me just now to tell me they look horrible AND when removing the injector rail, there are no seals underneath on that side. They are about to check out the drivers side and then call me again. Seals are either worn, gone, missing, fell apart, whatever... that also explains the staining under the cover and the burnt oil/gas smell I notice in the cab that I get at startup or when idling.

So.... any ideas as to underlying cause??? Its been under a year and 11k miles since injectors were done. What else can be causing this? IS THERE ANY WARRANTY FROM A CHEVY DEALER ON THE INJECTORS THEY REPLACED 10 MONTHS LATER??? Is it possible the injectors dont seat well within the head itself and this will just keep happening? Is there a better injector to replace it with? Could they have messed up the seals? Any thoughts at all??? I would think if an issue with the head was the case, I wouldnt have made it the first 80K miles without issue in the first place. I just dont want to have this keep happening.

Thanks, Chris