ok i posted about this before, but started a new post because the other one had the wrong topic.

i had the flutter in my rpms ...most of you figured vaccuum leak....i found a few hoses that were really old and dried out/cracked looking, and i finally replaced them. well i thought that was it, until i took a good drive....and what do you know....the idle did its little thing....the other vaccuum hoses looked ok.. i know i have that little vaccuum leak in the ac/heater controls-could that be it? or is there any where else it can come from??(seems i have heard about it leaking from bad plenum seal??) also, will it hurt to drive like this?

 

Check and clean your IAC if the rpms are only acting wired at idle.

 

what is the IAC and where is it? how do i check it and clean it?? thanks (oh yeah, 91 3.1)

 

It is the motor looking thing above the TPS on the throttle body. When your looking at standing from the front of the car it will be on the left (passagner's side) of the throttle plate. when you pull it out there will be a rubber stopper on the end of a metel pin with a spring. Mine was broken so I just got a new one, you may want to do the same. Then the hole you just spary some carb cleaner in and wipe it out. The IAC will have 4 wires going into it and 2 torx bolts holding it on.

 

cool thanks...i got some stuf on it off the archives too. thanks ryan, ill have to check that out. Oh..some on the archives said they cost around $90...is that about right?

 

NO LOL they cost about $30 dollars for our cars, thats why I recommended just getting a new one. Cheap insurance and you don't have to deal with it again.

 

I've read they say (mag writer) that the throttle bodies have a "film" to help prevent excessive build up.
This writer suggested find a "carb cleaner" for use in throttle bodies.
The writer said straight carb cleaner stripped off this "helpful accumilation build up" coating.
Me/
I never was told that & used carb cleaner on a shop rag to wipe out TB, I didn't spray straight on the TB.
Check hoses again, especially the underside.
Spray WD-40 on the seals of the intake listen for RPM change indicating a gasket leak.
YET, if your intake NEVER APART yet, chances it's a hose and build up of carbon in various spots.
Have you changed the oxygen sensor lately?
They go out after about 30K miles.
How wide is the RPM bounce?
Don't laugh, open hood at night time in the dark to check for electrical spark leakage, too.
I have some RPM bounce.
I attribute it to aged components & my lack of maintenance, as hard as I try to keep up with everything.
These 100* days really kill wanting to work outside in a hot hood of a car.

 

I heard that too, I think it was in Hot Rod mag or something? They make a specific cleaner for the fuel injection throttle bodies, I buy the one by Gumout, yellow can, red cap, "throttle body and air intake cleaner for fuel injected engines", right by carb/choke cleaner...

 

I thought it had to do more with O2 sensor apporved, that when burned the deposits won't mess it up forever.

The film there talking about, i've never seen, they never talk about it on honda's or ford mustangs when people send in their throttle bodies to be bored out so I think it's a mith. Maybe on some cars the cleaner may eat the anidized coating on some steel parts thus causing them to rust.

Hmmmm guess better safe then sorry.

 

thanks guys...im gonna look into this stuff this weekend.....i already checked the wires at night......my intake hasnt been opened......tell me about the oxygen sensor (im at college...dont have my shop manual here) i know that has not been changed...how do i check it? where exactly is it for that matter? thanks guys

 

if you've never changed the o2 sensor i'd replace it, cause its gonna effect your air/fuel because if its clogged or faulty it will send a signal to the computer to deliver more fuel or less fuel. it would be on the the exhaust system, weather down near the collector, or after the cat, i seen some cars have more than one o2 sensor. sometimes also they are a PITA to get off i ended up running the engine on my bird for about 5 mins and used a pair of visegrips to get it off, i bought that $15.00 o2 sensor socket with the cutaway for the wire and it just kept slipping. If you dont have one already try getting a chilton or haynes manual @ the auto parts store for your car. also ive had faulty o2's cause the car to hesitate or surge when driving.

 

90FirebirdV6, I had the same damn thing happen to me with that oxy sensor socket. Before we had it, I always cut the wire off the back of the oxy sensor, and used a "real" socket on the sensor, with a breaker bar. Then my dad goes and buys an oxy sensor socket for his cars, and it works for him. So I try it. Because of the slit in the oxy sensor socket, the socket spread open, and wedged itself on the damn sensor!! I had a hell of a time getting it off.

Once I got it off, I cut the wire off the sensor, and used a regular socket- it came off right away. What a $15 waste... but it -did- work for my dad's cars... go figure. Maybe our oxy sensors are in a spot that's more sensitive to corrosion?

 

Salt water slush splashing up on the underside of the exhaust in New Jersey winter time?
Corossion?
Nah!!!!!!!
How's the search for the EGR package? THANKS
Why couldn't GM place the part number on the EGR itself?

 

Yea...make sure when you're changing the o2 sensor...you don't strip it...cause thats what happened to me...mine was so rusted on there it wouldn't come off no matter how much i heated it...solution was that my uncle had a tie rod puller...that sucker gripped on it...and with a little help from my mapp gas torch and some mopar brand rust loosener (yes...mopar helped out the GM) that thing came right out...but thats just a forewarning...

 

When you take the oxygen sensor out I cannot stress enough HEAT IT UP. Seriously. If you do not heat it up your job will be ten times more difficult. Run the car for at least a few minutes, the hotter it is the better. If you wait for the car to cool off so you don't burn yourself, you're just going to smash your knuckles on the undercarrage anyway. Try from below with a large 7/8" wrench before you go buying a bunch of useless one-task tools. The only time I've ever used that socket is when I was putting the sensor on my headers before they were in the car.

 

LOL heating it up. Man try doing yours in a college apartment parking stall. I JUST DID. You know how I got it lose. All I had was an adjustable wrench and the spare tire jack, got the wrench on there real well and jacked it with the jack. NOW that seperates the men from the boys. I didn't even have the car jacked up, I had to reach down in there from the top and clip that wire with one hand. WOW took some time.