so this is my first monte carlo. it was givin to me by my aunt who said "it looks to hip for someone her age to drive" so she gave it to me. SCORE for me. plus its an SS

anyways she then tells me it has something wrong with it and has been sitting for a month or two because of this issue so the problem discribed is not because of sitting. she says someone told her it was the MAF.


so i did some searching around on some sites.

first
i pulled the iac and it was closed. when i say this i mean it was pushed all the way out blocking the hole that the plunger is supposed to block (at times). i read you can remove the iac but leave it plugged in, turn the key but dont start it and the plunger should move in or out.
so i did this and it funtioned , at that moment properly.

then
i took apart the mas and tested it as this site Testing mass air flow sensor directed me to.

i couldnt get a diffinitive answer on the ohms and when i tested it by blowing into it the volts didnt not fluctuate.

so i put it back together started the car and it started up and idled nice and smooth as if there wasnt any problems. so i took it across the street to get some gas in it. it drove great, no issue.

i get back to the house and let it idle, never turning it off. after about a min of idling it starts to go up and down like a vacuum leak would sound. so i unplug the mas and the idle just goes up to 3000 and sits there. i plug the mas back in and it starts stumbling again. so i unplug the iac and it stayed ****ty. so i plug that back in.
so i unbolt the iac but leave it in place. then i angled the iac alittle to let a tiny bit of air in it seems to level out. put her to bed for the night.
that was yesterday

today this is what i got. when i start it, it stumbles and then idles high for a sec or 2 then it comes down in r.shared_pm and fluctuates between 500 and 1000. then it will spike a hair (1500-2000rpm) sometimes and backdown. sometimes i can hear backfiring.
sometimes when i start it it stalls out, sometimes it starts fine. when it was stummbling i unplugged the MAF and it stalls the car, it didnt get better.

i went and bought some CRC MAF cleaner tried that it seemed to level out alittle(mabey) but still rough starts. i checked the k&n filter it was clean.

it is throwing a code i have to get it across the street to have it scanned.
im sure ill have more answers after that
but do you guys got anything before then?

 

so about 2 hrs after i cleaned the MAF with CRC MAF cleaner i went out and started it it stumbled allitle on the first try but started. then i tried again and it started up fine. i then look down and the CEL is gone. i turn the car back off and on again and it starts right up as if there was never a problem.
so i wait another 2-3 hrs and go back out and start it and it starts up as if there was never a problem again and still no CEL.
it was 25 deg outside and it still started up smooth on first try.
im sure the MAF just had to be cleaned. i havent been able to drive it yet cause it was blocked in the driveway by a roomate.
ill let you guys know

 

so i start it this morning and its back to shitass. so i bring it across the street to get scanned. they call me and tell me the CEL is from a coilpack and that the TPS and IAC are all bad. mabey the coilpack(s) are bad but i think the others are bs because i tested the IAC and the TPS with the volt meter the way this vid shows(great how-to by the way). so i will start with the coil packs first and go from there.
ill let you know

 

If its your coil packs the car will misfire, at least thats wut mine did when one of my coil packs went bad. My impala use to stall out after start up and i replaced the mani o2 senor and that fixed it, u might wanna replace the o2 senor near the cat conveter. Or it could be a vac. leak.

But here bro, go to this site North American Impala Owners Association - They can help u out more wit ur problem. Its for Impala/Montes/Regals/Grand Prix. Strictly for the w-body cars, wit the 3400 or 3800 series II and III engines. Supercharged, turbocharged, or None.

 

put in a new tps, iac, and coil packs as the garage said that that was the problems and none of them fixed it. should i get a maf?
sometimes it runns strong down the road and other times it dogs down the road. if i cant get it started or it is idling near death if i unplug the maf it does get better but not by much. does it sound like the maf?

 

Yes i would change the mass air flow now.....

 

i find it bs that the garage tells me its 3 or 4 diff things and it was none of them. anyways i got to return all the parts to autozone so im not out any money, till i get the maf. im gonna be extra carful not to dirty up that one so i can send that back if its not the problem.
i wonder could it be the crank or cam angle sensors. and it was would they definatly throw a code?

 

Most of the time as in 99.8%,with bad crank and cam sensors they will throw a code. And or the car would not run at all. There is a very slim chance they wont set a light.

As far as the "other" codes. If they did pull those codes with a scanner, they are there for a reason. With any of your testing did you unplug those with the car running other then coil? If so, then thats why they are in the memory of the computer. The coil is a diffrent story.

Theres is a strong liklyhood you are/have been dealing with more then one problem with this car. I would keep the coil, return the others and put a mass air flow on it. The only other thing i have to ask is, have you or some one else checked fuel pressure?

 

changing the MAF tomarrow. ill keep you posted

 

MAF changed and it seems to be solved.