Car broken

[Scouzer]

3.1L V6

When I start it, there's a loud awful noise--I'm not sure if its a squeal or a really really loud woosh, ie a vacuum leak. It idles like a maniac, all over the place...and this problem spawned overnight. Nothing was wrong last night...

Thoughts? I'm thinking just a really bad vacuum leak...but I don't know.

 

[CraigRT]

When you say it idles sporatically do you mean it jumps up and down like the beat of a song? (up, down, up, down, up, down) or is totally whack not idling to a pattern?

 

[Scouzer]

Well, I suppose it could be to a beat of a song. But it doesn't goto the same rpm, 2000 to 1000 then to 1800 then 1200 then 2000 etc...its all over the place.

 

[CraigRT]

Hm, could perhaps be the IAC... does the car throw any codes?

 

[Scouzer]

Nope. The check engine light comes on after running 5 seconds, but when I do the paperclip trick no codes come up.

 

[CraigRT]

not sure what the paperclip trick is but that seems strange that there is a check engine light with no codes... IIRC most cars can actually have soft codes (battery disconnect, etc) which means the CEL does not even come on, but when the light comes on, usually tells you, you have a hard code. (sensor malfunction)

 

[Scouzer]

Paperclip trick is when you actually short out a part of the OBD hookup and it will blink the check engine light. You count the blinks, that's your code.

I get a code 12 which just means diagnostic system is functioning normally.

 

[CraigRT]

can you do it while the car is running or did you try it with the car running?

 

[Scouzer]

no it only works with the car in the last click of the ignition BEFORE turning it on. but the computer normally is supposed to save any codes that popup, i dont know why it isnt

 

[CraigRT]

Yeah, that's definitely weird... just thinking scanning while the car is running should obviously spout the right code... hmm

 

[Pepsi90919]

Originally posted by: CraigRT
Yeah, that's definitely weird... just thinking scanning while the car is running should obviously spout the right code... hmm

that might be the only option. the paperclip trick is great for the GM OBD I cars otherwise.

 

[Scouzer]

any further thoughts?

 

[RU482]

sounds like either a vacuum leak or throttle position sensor gone completely whack

 

[Scouzer]

the TPS wouldnt make that noise would it?

 

[Black88GTA]

Not by itself, but if it is throwing erratic readings, it could put the idle all over the place. Although, that doesn't sound like it - usually the TPS won't randomly change readings like that if it is sitting still.

Not saying that's definitely not it, but I'd look hard for vacuum leaks before messing with that.

 

[Scouzer]

Turned out it was in fact a vacuum leak. I got my oil changed & starter replaced (unrelated problem) for $308 CDN. Not too horrid, I guess.

Downside was that when I went to pickup my car, the mechanic left a different vacuum line unplugged so he had to run out and fix his mistake....and they broke my oil pressure gauge on my dashboard and claimed no responsbility... oh well..