neo8222

hey, hate to burst your bubble but when you have a cracked header, exhaust gas leaks out and air bleeds in, thats an exhaust leak, so wouldnt it stand to reason a cracked manifold/header is a exhaust leak?

WoahPony

^^^ I was just gonna keep my mouth shut.

sugar58

okay so, we ruled out a few things. we went to a place and they checked the vacuum hose, checked for any leaks and there is no fuel leaking from anywhere and my exhaust is all fine. BUT there is a teeny crack where the header (manifold) connects to the engine (i dunno, w/e it connects to) and you can barely see it from where you look inside the engine bay. they said they can take it off and weld it but that it's such a tiny leak that when my car heats up, it expands and won't leak, it's only when my car is cold?? so that wouldn't be the problem for this fuel problem. my check engine light bulb is fine too, cuz when i go to start the car, all my lights come on, so it's not a blown bulb. so what we're looking at now is ....
a) faulty mass airflow sensor?
b) faulty o2 sensor?
c) fuel pressure problem?
any other ideas of what it could be? thanks!

Synyster06Gates

Your leak can still be causing problems. Usually it's a crack on the side of the manifold you can't see along the collectors. I couldn't even see my cracks because they were so small, but they had a profound effect on my mileage and the way my car would run.

You can try to replace the O2 sensors, but I doubt it if would make a difference. I don't think it's a fuel related problem unless an injector is stuck.

sugar58

okay, so i will get that leak fixed asap when i get some $$$$. and my b/f is going to crawl under my car tomorrow and take a look at the o2 sensors and see if they're dirty or look bad. i'm really hoping it's not a fuel injector because to my knowledge, that's something hard to diagnose and expensive to fix? thanks again

and also, if i were to go and find the o2 sensors look bad, would these be the right ones to buy for all 4?

http://www.car-stuff.com/carparts/fo...t=SEO+Page%3A1

WoahPony

if you wanna get your manis fixed for cheap buy mine haha =)

neo8222

you can't tell if a o2 is bad by looks, it's a problem with carbon coating the elements inside the o2 that you can only see if you take it apart which will destroy it and make you need new ones anyway. best bet is to just replace the front two first depending on how many miles your car has and if problem persists after checking all other avenues that could cause the problem replace the rear two.

sugar58

you're selling yours? how much? haha

well that sucks about the sensors... so you think i should just replace the front ones first, see what happens and if that doesn't work, replace the back ones? and why the front ones first? as far as i know, they've never been changed, and i'm at 116,000kms at this point. thanks

SteezyMustang01

I am having a P0401 EGR fault on my 2001 3.8L, I've replaced everything but the pipe for the EGR system. But the stupid EGR insufficien flow fault keeps popping up. I have brand new short tube headers and catted X-Pipe for a true dual system on my car. Please help if any ideas, I am getting so frustrated!!!

MustangSally94

First place you might wanna start is your own thread instead of reviving one thats been dead for almost 4 months