HUGE sensor issue

[RadRacer]

OK, I've been through two MAF's already on this car. When I got a code saying it was bad again I didn't think much about it. Went out and got a new one (bought one with lifetime replacement last time, so it didn't cost me squat) and put it in. Cleared the code with my Uncle's scanner and thought all was good. Cranked it back up, reach around and put on my seatbelt and my SES light pops on again. Same code: MAF sensor low circuit. We took it out, cleaned it all up and checked everything. So, we start thinking wiring or computer issue. Quick look around doesn't show any wires broken or pinched. Most recent mod was headers, and still that was almost a month before this began. Pulled the fuse box cover for no reason at all and notice a fuse blown. It's the engine sensor fuse :(. We pulled it and replaced it. Blew immediately. Tried a 25A just to see what it would do and it blew immediately (5A bigger then needed). My Uncle hooked his scanner up and put it in real-time mode so we could see what the sensors said. My MAP sensor wasn't getting anything, my MAF wasn't getting anything, and my TPS was messed up, along with a couple others. Tried unplugging the MAF thinking maybe we got a bad one that was causing it, but it still did it. Even blew a 30A fuse. So, we're thinking that when I installed headers, I may have not gotten a sensor's wire routed right or something and it burnt up, now grounding the whole system. Any suggestions/ideas as to where to look? I wanted to get my nitrous system installed this upcoming weekend, but would much rather get the car running right first.


BTW- when we did this, we also came up with a bunch of codes. I'm certain they're all related to this problem, since they were all TPS, MAP, MAF, and O2 issues.

[RadRacer]

Re: HUGE sensor issue

Dang 97rs4life, moved that one quick :D. Wasn't too sure if I should have posted it here or not since it seems more of a wiring issue than a sensor issue, sorry 'bout that.

[Shirl]

Re: HUGE sensor issue

I had a similar situation with an 02 sensor code (and blown fuses). Changed one 02 sensor (this was on my 97' Cavalier) and the code went away for a few hours and then came back! Confused, I went to change the second one out in the y-pipe and found the burnt sensor wire.

Seems when I had my exhaust re-welded (after it broke apart near my intake manifold), the muffler shop screwed up and didn't re-route the 02 wire AWAY from the hot exhaust when they re-connected the 02 sensor into the y-pipe. Their mistake cost me at least 100 bucks in sensors, not to mention time trying to figure out what was wrong.

I'd have to say whatever you did last, caused this to happen. So DEFINATELY check around the headers for burned sensor wires. Most likely, there is one laying on the headers somewhere.

[Nachius]

Re: HUGE sensor issue

Definitely sounds like a short with a wire being grounded or broke somewhere.

No easy way to trace them either. Look at the Pin out for the PCM so you have some idea which wires to follow.

[RadRacer]

Re: HUGE sensor issue

I had a similar situation with an 02 sensor code (and blown fuses). Changed one 02 sensor (this was on my 97' Cavalier) and the code went away for a few hours and then came back! Confused, I went to change the second one out in the y-pipe and found the burnt sensor wire.

Seems when I had my exhaust re-welded (after it broke apart near my intake manifold), the muffler shop screwed up and didn't re-route the 02 wire AWAY from the hot exhaust when they re-connected the 02 sensor into the y-pipe. Their mistake cost me at least 100 bucks in sensors, not to mention time trying to figure out what was wrong.

I'd have to say whatever you did last, caused this to happen. So DEFINATELY check around the headers for burned sensor wires. Most likely, there is one laying on the headers somewhere.

Actually, I had the full exhaust and headers put on at the same time. Situation sounds very simlar to yours, hopefully it's just a burnt O2 sensor that I can easily replace. This weekend I'm going at it with a multimeter probe to see if I can find a short anywhere.

[tcrocker162000]

Re: HUGE sensor issue

if you just installed headers and its shooting codes, you may have a wire to close to the heat those headers are producing, which would cause a short of that wire is burnt up, that sounds like a s***ty problem, i hate senors

[RadRacer]

Re: HUGE sensor issue

if you just installed headers and its shooting codes, you may have a wire to close to the heat those headers are producing, which would cause a short of that wire is burnt up, that sounds like a s***ty problem, i hate senors

I hate sensors too. Besides the stalling, the car's not really running bad. It's inconsistent though. Actually, I just took it to the track Sat night and ran my new best :D, along with my new worst :(

[tcrocker162000]

Re: HUGE sensor issue

thats awsome man, i acctually havent put headrs on my car just because i dont want to deal with the heat i have to drive it home everyweekend from college and i just cant afford anything to go wrong with it right now, i just went for appearence mods for now

[RadRacer]

Re: HUGE sensor issue

thats awsome man, i acctually havent put headrs on my car just because i dont want to deal with the heat i have to drive it home everyweekend from college and i just cant afford anything to go wrong with it right now, i just went for appearence mods for now

I hear ya man, but I personally hate all show and no go cars. My car ATM looks pretty good. Could be better, but I'd rather go faster and look good, then look really good and be slower.

[tcrocker162000]

Re: HUGE sensor issue

haha oh trust me, i would too, but that college payment henders that going fast part very badly, im gunna run this car thru college, then get a v8 fbody and do all the work to it, i have a 1979 trans am in the garage, so i have something fast, i just cant afford to insure both cars and keep them both going lol sucks being under 24...i just dropped a grand in books today BLAH I HATE SCHOOL

[RadRacer]

Re: HUGE sensor issue

haha oh trust me, i would too, but that college payment henders that going fast part very badly, im gunna run this car thru college, then get a v8 fbody and do all the work to it, i have a 1979 trans am in the garage, so i have something fast, i just cant afford to insure both cars and keep them both going lol sucks being under 24...i just dropped a grand in books today BLAH I HATE SCHOOL

Know how ya feel. Books cost me $650, tuition is a whopping $26K per year, not including room and board (lucky enough to live locally). Only reason I can afford anything for my car is cuz my grandma built up a college fund for me.

[tcrocker162000]

Re: HUGE sensor issue

thats awesome

[99pewterv6]

Re: HUGE sensor issue

Dang 26K per year?!?! I'm on my 5th year of school here and haven't even reach 26k. About at 25K right now though.

[RadRacer]

Re: HUGE sensor issue

Finally figured it out. I recently had my exhaust redone to 3". When it was put on, it didn't occur to me that my O2 sim would be closer to the exhaust heat. Well, it ended up melting some, so it was not working properly and causing the whole sensor circuit to go crazy. Pulled the sim out and she runs perfect again :D. Also fixed a few exhaust leaks I had while I was under there!

[97rs4life]

Re: HUGE sensor issue

great to hear! Now spray that thing