Rough idle?
 

i have a 2001 chevy suburban LS

i noticed this morning that it wasnt ROUGH ROUGH, it was just dropping rpm a little, i figured it was because it was cold, because once it warmed up, it was fine. the check engine light is on, so i took it to autozone to check the codes.

i got back a few different things, one being a MAP sensor, another one being random misfires. so the first thing im thinking is tune up, and replace the sensor.

should i be starting there? or is there something im missing.

fyi, starts fine in the morning, no issues, runs great, while driving, no sputters at all. just at idle.

Maybe bad gas? have you recently filled up? might try a fuel additive and some fresh gas from a different station...

yeah i got about 40 in fuel from walmart.

but that is kind of besides t he point, with the error codes being given, and a few of those that can cause this type of idle...

Might want to post the codes you got, this will help others chime in on possible causes....
Keep in mind the codes that are set may not be the actual problem but the symptoms of something else...

P0171
P0332
P0300
P0174

That's the codes it gave me.

May want to try cleaning the throttle body
Check for any vacuum leaks, loose air intake hose, and other hoses and lines that go to and from the intake manifold...
The code for the knock sensor could be valid...

Bad fuel can cause all sorts of problems.
Get a jug of the "RED" alcohol{Isopropyl I think} sold all over,convenience stores etc.If You have 20 gallons of fuel in the tank dump in two jugs more if it is fuller.Dont use alcohol al the time,only if You are having problems.It can destroy the fuel lis if used ll the time.
Pull a plug or two and se that they are OK.lso use a jug or two of fuel system cleaner,injectors coul be getting dirty.
Also perform all of the step afore mentioned.

yeah im going to give it plugs and wires and probably change out the MAP sensor and see if that solves anything, im also going to clean the throttle body.

i looked up the bad gas stuff, pumps come with a built in filter that shutdown automatically if there is bad gas. since my father in law got gas at the same time i did, he hasnt had any problems. im going to clean the throttle body, i saw some kind of deal where the 200-2003 swuburbans and some other vehicles have an issue where they get build up and cause idle problems.

Might run a couple of bottles of Techron FI cleaner thru it. Won't hurt.