Hi guys, I know there are a lot of threads talking about codes popping up and I've been looking through them but still haven't found the solution for my truck. Here we go, its a 04 Silverado LS RCSB 4.8 with 79xxx miles, it has a whipple side mount, catless (hadn't turned a check engine light for about a year),and a tune.

Well about a week ago it started idling rough after 200 miles of a 550 mile trip, we came to a stop sign, it started shaking and the check engine light turned and after I got home to Houston and turned her on the next day it turned off and remained off until I came back to school, 150 or so miles into the trip this happened again, we came to a stop and it started shaking bad and bad fuel economy began.

Before it was acting up it would give me 21-23 mpgs and during about 11-13 mpgs on highway. Got her checked out and it threw 4 codes, p0171, p0174, p0200, p0300. All I did was wiggle the injector and the light turned off. Then the light turned off on its own yesterday and today it came back.

What do you all suggest it is or I check before having to drop some money at a shop? Any help would be greatly appreciated, thanks in advance everyone.

 

maybe the p0200 issue screwed with your cats and now the catts are dammaged giving you the misfire code.

 

P0171 and P0174 are lean codes for each side

P0200 is injector malfunction & P0300 is random or multiple misfire.

(I just looked them up, I only knew the 0300 due to mine's thrown it before)

I'd be careful driving if you're throwing lean codes, especially running FI...

Almost sounds like your injectors aren't firing, however I'd think that it's have to be a cyl. on each side to cause both banks to show lean.

Take it with a grain of salt, it's just my two cents... sound like it could turn into one of those troubles in a real hurry.

 

Update, light turned off and now shes acting like nothing happened...

 

bad fuel, **** got in the injectors?

 

Light turned back on again...

 

it could be a number of things, but i sure wouldnt drive around lean tho. Check over your coils, injectors, spark plugs, and throw in some injector cleaner.

My truck last month was doing somethin similar, but it said random misfire on cylinder 5. It ended up being a very bad spark plug, lol. Hope this helps.

 

Thanks everyone for the input, now I'm just getting lean codes on both banks and the 300, I will put on some injector cleaner and hope that helps.