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04 5.3 is driving me to drink! P0174, rough idle,

whiteghost94

Full Member
Joined
Dec 1, 2015
Messages
21
Ok, so I pulled my trans and fixed my oil leaks, put it all back together and now I am setting off the p0174 code along with the p0300 (yes, they go hand in hand) I can shut the truck off for 5 seconds and restart and it runs like it always has for a while again (10 min, a day...it's totally random) my o2's seem to be reading fine, I sprayed a whole can of carb cleaner around the engine checking leaks and no response from that, I changed the maf since cleaning my old one helped for a day, went for a 408n drive and I got the rotten egg, codes, rough idle at a stop light again. Restarted and it ran fine for another 30 min and I shut it down and haven't drive it since.....any help her guys?
 
whiteghost94 said:
Ok, so I pulled my trans and fixed my oil leaks, put it all back together and now I am setting off the p0174 code along with the p0300 (yes, they go hand in hand) I can shut the truck off for 5 seconds and restart and it runs like it always has for a while again (10 min, a day...it's totally random) my o2's seem to be reading fine, I sprayed a whole can of carb cleaner around the engine checking leaks and no response from that, I changed the maf since cleaning my old one helped for a day, went for a 408n drive and I got the rotten egg, codes, rough idle at a stop light again. Restarted and it ran fine for another 30 min and I shut it down and haven't drive it since.....any help her guys?

Fyi, I tried the carb cleaner thing on my 03, and could not locate any manifold leaks, went through 8 o2 sensors thinking I got a bad bunch first time I changed it....I ended up as a last resort just changing out the manifold gasket anyways as I was out of options, and alas, all codes cleared right up, and engine rankings absolutely fine for 2 years now.....until my recent fuel pump issue
 
Well I guess the only reason I'm hesitating doing the intake is because it's awful coincidental that it just started on my test drive after tossing the tranny back in....I guess I'm kinda out of options cuz everything seems to be leading back to the intake!
 
https://www.obd-codes.com/p0174

MAf sensor clean?
Air plumbing after MAF leaking air into engine?
 
Well if this is an intake leak and the engine is getting air it can't see... If you unplug you mass air flow sensor the truck will still run. Start it and it may die once but after that you should be OK. I'm not sure how it will work but I'd try to do that and then very grandpa like drive around block and see what happens. It use to be an old trick we used in the 90's to get GM cars home when a mass air flow sensor died. Keep in mind that would of made them early 90 cars since I was a tech at a non dealer . If you try this DO NOT BEAT ON IT FOR GODD SAKES!!! This is just a home made limp mode. It might even through a newer car in limp mode.
 
Yea I cleaned my original with maf cleaner and like I said it helped for a day, my buddy had a good one he took off another truck so I tried just changing it out completely and it ran great for about an hour...the o2s seem to be reading but I wonder if I should just try changing out the upstream on bank w just to see if it helps  : ???
 
Did the b2s1 oxygen sensor, intake gaskets, plugs, wires and put my old maf back on...no luck after the intake gaskets, still had the same problem. Drove it again for 44 min and ended up getting a insufficient switching code from the b2s1 02, changed that and plugs, wires I guess we will see what tomorrow brings
 
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