returning check engine light
 

Its starting to get cold around here and every morning when I go out to start my truck my truck throws a "single/multiple cylinder missfire code" And everyday I clear it with my code reader. Any one have any ideas why it would be throwing this code continually? Im wondering if its from it having a custom program maybe.

RE: returning check engine light
 

do ya feel a miss?

RE: returning check engine light
 

it runs rough sometimes.

RE: returning check engine light
 

most of these phantom misses are due to injectors...if its a hard miss,look more at the p[lugs or wires

RE: returning check engine light
 

Ok maybe its the wires, the plugs are newer and the wires are original so thats my next bet.

RE: returning check engine light
 

O2 sensor will also throw the same code

RE: returning check engine light
 

an 02 sensor will not set a misfire code on one cyl

RE: returning check engine light
 

change your plugs that just happened to me. it's fixed now code went away

RE: returning check engine light
 

Well it threw a lean bank 1 code and a lean bank 2 code this morning. But I turned the truck off and check the codes again and the only code was the cylinder miss fire. So im not sure what that all means?

RE: returning check engine light
 

has it had a fuel filter>?..could it be ****ty gas?

RE: returning check engine light
 

No offense Argon, but it says Single/Mutiple cylinder mis-fire and my truck does it all the time due to theO2sensor readings I get from removing my cats.

RE: returning check engine light
 

well,if all 4 sensors are gone,who knows wtf...but 1 03 sensor being lazy or skewed should not set a 300..

if your repeatedly setting a 300,it must get some awful mpg

RE: returning check engine light
 

its bin good this week. fuel filter only has like 15000 on it just like the plugs.

RE: returning check engine light
 

If it only does it when it's cold then it's probably intake gaskets leaking. Try this: when you start it cold, take some brake clean and spray around the intake and see if the idle changes. if it does, then your intake gaskets are leaking. If its a 5.3, that's a common problem. GM has updated gaskets for them. I've replaced alot of them (I'm a tech at a GM dealer). They'll run you about $100. They're not too bad to replace. Also, if you're running aftermarket spark plugs, put AC Delco in it. Fixed alot of misfires by replacing aftermarket pulgs with Delco.