Just got done putting injectors in my 2009 Envoy. It my have taken me an hour total to tear it down and get it back together after doing this job 4 times altogether. It's had this code for a couple of years at this point. By now, I changed everything else they recommend to change for that code and nothing fixed it.
Finally got to the point that it would barely run so I replaced the injectors. This thing purrs now and that stupid code hasn't come back in 4 days.
I knew it was the injectors but I was expecting it to take longer than 1.5 hrs to swap them out so I kept putting it off. There's also the fact that injectors were $125 each at O'Reillys. I got AC Delcos from Rock Auto for $35 each. $210 for all 6
Man this thing runs good.
And I haven't even gotten into the story about the POS shop I took it to. I was 95% sure it needed injectors but took it there for them to confirm my diagnosis before I spent all that money. At the time, I thought by injectors were still $100/each. They tell me I need valves and the engine should be replaced. The next sentence? Oh it has good compression on all cylinders.
Yeah? It ain't the valves then. Dumbazzes. I took my truck home and pulled the intake and replaced the injectors. I asked if they checked the injectors. The service manager started stumbling his words.. I Said you know... An injector balance test? I brought it here because I can't check that and I'm pretty sure it needs injectors. "Oh oh yea. They're good" is what he says. smdh. 100% sure they didn't check them.
This is exactly why I learned to fix my own vehicles at 15 yrs old. Shady, incompetent shops. I told them they're incompetent from the top to the bottom. From the POS parts changer that couldn't diagnose my truck to the service manager that was clueless about everything.
Anyway. If you have a P1174 code and a MAF and O2 sensor don't fix it, replace the injectors. It's a 2 hr job tops.
I ended up replacing the valve cover gasket at the same time due to my own stupidity. I blocked the port on the top of the valve cover with a rubber cap and it blew oil EVERYWHERE when I drove it lol. Out the back of the valve cover onto the firewall. Into 4 of 6 spark plug tubes. It sucked. The tubes were full of oil so I just pulled the plugs and let it drain into the cylinders, then thinned it out with Seafoam so it would drain into the pan. That was fun lol. Yes, I'm an idiot lol. I know. Had to clean the coils with MAF sensor cleaner. Replaced the plugs. This things runs immaculately now.
Why did I take it apart 4 times? I replaced 3 injectors the first time because 3 cylinders were misfiring. Had to pull it back apart for o-rings. Then had to pull it apart a 3rd time to replace the valve cover gasket when I blew oil everywhere. And a 4th time to replace the other 3 injectors. Replacing the last 3 injectors took an hour from start to finish. Lol I got pretty good at pulling the intake. For example, You don't even have to remove the alternator. Just move it to the side so you can reach the bolt behind it. I figured that out the 4th time lol
Finally got to the point that it would barely run so I replaced the injectors. This thing purrs now and that stupid code hasn't come back in 4 days.
I knew it was the injectors but I was expecting it to take longer than 1.5 hrs to swap them out so I kept putting it off. There's also the fact that injectors were $125 each at O'Reillys. I got AC Delcos from Rock Auto for $35 each. $210 for all 6
Man this thing runs good.
And I haven't even gotten into the story about the POS shop I took it to. I was 95% sure it needed injectors but took it there for them to confirm my diagnosis before I spent all that money. At the time, I thought by injectors were still $100/each. They tell me I need valves and the engine should be replaced. The next sentence? Oh it has good compression on all cylinders.
Yeah? It ain't the valves then. Dumbazzes. I took my truck home and pulled the intake and replaced the injectors. I asked if they checked the injectors. The service manager started stumbling his words.. I Said you know... An injector balance test? I brought it here because I can't check that and I'm pretty sure it needs injectors. "Oh oh yea. They're good" is what he says. smdh. 100% sure they didn't check them.
This is exactly why I learned to fix my own vehicles at 15 yrs old. Shady, incompetent shops. I told them they're incompetent from the top to the bottom. From the POS parts changer that couldn't diagnose my truck to the service manager that was clueless about everything.
Anyway. If you have a P1174 code and a MAF and O2 sensor don't fix it, replace the injectors. It's a 2 hr job tops.
I ended up replacing the valve cover gasket at the same time due to my own stupidity. I blocked the port on the top of the valve cover with a rubber cap and it blew oil EVERYWHERE when I drove it lol. Out the back of the valve cover onto the firewall. Into 4 of 6 spark plug tubes. It sucked. The tubes were full of oil so I just pulled the plugs and let it drain into the cylinders, then thinned it out with Seafoam so it would drain into the pan. That was fun lol. Yes, I'm an idiot lol. I know. Had to clean the coils with MAF sensor cleaner. Replaced the plugs. This things runs immaculately now.
Why did I take it apart 4 times? I replaced 3 injectors the first time because 3 cylinders were misfiring. Had to pull it back apart for o-rings. Then had to pull it apart a 3rd time to replace the valve cover gasket when I blew oil everywhere. And a 4th time to replace the other 3 injectors. Replacing the last 3 injectors took an hour from start to finish. Lol I got pretty good at pulling the intake. For example, You don't even have to remove the alternator. Just move it to the side so you can reach the bolt behind it. I figured that out the 4th time lol
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