car seeems to be running rich

hognutz · Dec 13, 2005

this is a new issue and plugs have been replaced. The only sensor I can think would be in issue would be the MAF. It measures the ariflow if it was off the car would run rich. If the O2's were not responding right I am assuming the would have a code thrown. is there any other places the proablem could be coming from. no light is on but milage is down and the exhaust smells rich.

tomustang · Dec 13, 2005

have enough threads?

east_sidaz40 · Dec 13, 2005

holy crap a 5x post

hognutz · Dec 13, 2005

damn computer at work kept saying page cannot be displayed so i would try again. Can't belive it did not see them a duplicate. I know on replies it would not let you duplicate. there is no way i can find to delete them either.

Mustanggt108 · Dec 13, 2005

tomustang said:
have enough threads?

I was just about to say that. You stole my words

Thread owner..no worries things like this do happen sometimes

timeless2 · Dec 13, 2005

Did someone say "Clean up on aisle 4.6 please!"?

hognutz · Dec 13, 2005

My pc at work does not like this message board sometimes it will just sit there locked up. Most of the time the post or reply does not go through. my computer at home I have no issues. I would ask the NA but I am supposed to be working not surfing.

hotmustang331 · Dec 13, 2005

That sucks huh? (#4)..Oh wait this is the REAL one LOL. But seriously its probably the MAF...and it wont throw a code (just lean in bank 1/2 or rich in bank 1/2..if it gets bad). Clean it out and see if that does it...search for ways to clean it as I dont know lol.

hognutz · Dec 13, 2005

okay I will search on MAF threads. just trying to makes sure I am not missing a simple solution.

hotmustang331 · Dec 13, 2005

Cool...but thats pretty simple (and basically free). NOW if you have an aftermarket MAF (dont see it in SIG) but it would most likely need to be replaced with a factroy unit...aftermarket MAFs SUCK save for some of the 90MM ones from like SCT...but I would ONLY go with a lightning 90MM MAF if I were to upgrade.
Other possabilitys would be a bad 02 sensor in the exhaust...im not too sure which ones control/contribute to the A/F setting. You have the upstream ones (before cats) then the ones after the cats...im pretty sure the front ones do it but dont quote me.
That would be my second place to look if this doesnt do it.

hognutz · Dec 13, 2005

no I have stock maf. I have avoided the maf mod as I don't have the power to need a new one yet.

I do plan on getting a KB 9psi this summer so if my maf is bad I may think about going with a lightning maf now.

anyone know an easy way to test to see if the maf is out of range or bad if it is not just dirty. does not seem like there is much to clean on a maf.

my understanding is the post cat are just for odbII basically verify the cats are good. the pre cat 02's will affect you tuning but I would think they would throw a code buy maybe not.

those are the only two things I can think of but I could be missing something. problem is a maf is not amazingly cheap and don't think the 02's are cheap either so I would like to kind of troubleshoot it if I can to verify a problem. I would hate to spend $400 and then have it be something simple.

John Smith · Dec 13, 2005

How lean does it have to get before it throws a code? I had my car on the Dyno last weekend and it ran really lean, but there were no codes.

DocG · Dec 13, 2005

Clean MAF with electronic contact cleaner. You should be able to check it with an ohmmeter...but not sure what readings it should show for normal.

How does exhaust smell rich? I can see noticing color changes or oil on the hand, but smells...haven't had to try that one yet!

Have you tried resetting the computer by disconnectnig the battery. Am I confused, or doesn't running rich mean too little fuel and lean mean too much fuel..kinda backward of common sense? I though lean led to detonation, or is it the other way around?

hognutz · Dec 13, 2005

running rich is too much fuel and you can usually smell it if it is extreme. I would think this would set a code but it has not. I originally though maybe the pvc was bad and some oil was being sucked into the inake but I put an inline air to oil separator in and smell is still there.

no I have not reset the computer when I try cleaning the maf I will do this as well I guess.

DocG · Dec 13, 2005

Ok...makes sense...confusing myself, been a long day.

Well...I knew I've seen articles on how to check MAF and other sensors. If you're still having trouble...go pick up a Haynes manual. Pretty detailed section on how to check MAF for normal operating ranges, IAT, etc. I'd try to type it all in here, but its a lot of info, and would be hard to sum up. Oh, you'll need a multi-meter too if you don't have one.

DocG · Dec 13, 2005

IAT may cause rich conditions too since it senses air temp and controls fuel mixtures.

hognutz · Dec 13, 2005

already got the multimeter that is not a problem. Guess I will go pick up a manual on friday. see if it has the info I need.

okay Idle air temp sensor. I will look into that as well. might just order an xcal2 to try to help me datalog a bit. get the wideband add on as well. I don't like this flying blind bs. I will just tell the wife. hey, you get your ass to work and work some overtime. I need more toys.

hotmustang331 · Dec 13, 2005

INTAKE AIR TEMPERATURE sensor. It senses the temp of the air and corrects the fuel and timing to compensate for the densety of the air. Cold air means MORE air in, and if the EEC added the same amount of fuel, the car would go lean...so it adds fuel ands timing (since cold air is less resistent to detination) on cold days...and pulls fuel/timing on worm days. Thats why our cars SUCK on hot days.

DocG · Dec 14, 2005

hognutz said:
I will just tell the wife. hey, you get your ass to work and work some overtime. I need more toys.

That should work out well for ya!

And yeah..IAT is intake air temp sensor. I thought about mentioning a Xcal and doing data logging, but seemed like an expensive option. The manual outlines checking all these sensors, that will at least let you know if any are bad, and go from there...seemed pretty easy too if you follow the manual. If I had a scanner, I'd scan it in for ya.

hognutz · Dec 14, 2005

I think I might be getting gears for christmas so I will need to do something in that case anyway. So I think I am just going to bite the bullet and get the xcal 2. I think it will tell me what my iat and stuff like that is reading so it should be easy to spot an issue. if it say 140degrees at startup or somthing I will know there is something wrong.

Wife works for ups so she is working mad overtime right now. So I will just say whats mine is mine and whats yours is mine and I am buying myself the xcal2 for christmas.

car seeems to be running rich

New Member

Psychotic Member

New Member

New Member

New Member

Vi Veri Veni Versum Vicus Vici

New Member

Active Member

New Member

Active Member

New Member

New Member

5th graders > me. They're not bant

New Member

5th graders > me. They're not bant

5th graders > me. They're not bant

New Member

Active Member

5th graders > me. They're not bant

New Member

Similar threads

Privacy & Transparency

Privacy & Transparency