Bow94z

car has 124k on it...its got a slight hesitation in low rpms. this weekend im thinkin bout new oxygen senors, Throttle position sensor, and possible IAC, what does IAC exactly do? ALso is it worth buying a new egr valve or just clean my existing one... car has new plugs and wires, fuel filter. just curious if this tune up is worth anything to me.

im gonna clean the hotwires on the MAF, heard that is good when using oiled filters

DonHood

Definately get new O2's with that many miles, that could be all of your problem right there. The IAC is the Idle Air Control valve. When I took my throttle body off and cleaned it, I got a ton of buildup out of it's port, and I'm sure that helped it out a lot. Gave me piece of mind anyway. I wouldn't worry about the TPS unless you're throwing a code for it, they seem to rarely go out. I've never messed with the EGR, but I'd assume it'd be easier to replace than to clean/repair.

Bow94z

would O2's always throw a code? do i need two 02 sensors in a 94?

people say the TPS gets flat spots on it or something.... could it hurt to throw a new one in?

Bow94z

also are the 02's hard to install?

z28marine

the driver side O2 is really easy to remove....comes right out with a wrench...the passenger side is a little different. You will want to take off or move the starter, and might have to weld the O2 sensor off. Mine was impossible to get off when i tried. I literally had to stomp on it to remove it from the manifolds when i took them off for my headers. Some people said the put a flame on it to loosen it up...all that carbon building up on it makes it stick really bad.

Greasepunk

1. O2's will throw a code.
2. Yes you have 2 O2's.
3. TPS does get flat spots, couldn't hurt to replace it.

IAC- Idle Air Control.

Cleaning the MAF, be very cautious, it's sensitive. I would use some electronics cleaner.

Wouldn't hurt to replace the coil also since you just put in new wires, it's relatively inexpensive. I would also clean the MAP sensor. (Manifold Absolute Pressure)

Bow94z

coil was replaced few months ago...

cleaning the map sensor...its the little black box ontop on of the manifold... ways to clean it???

Greasepunk

MAP

Spray carb cleaner in the hole upside down so all the build-up drains out. I also sprayed some let it soak then gently tapped it on a towel to shake the excess out. Then you just let it dry for awhile and put it back on.

*note, the green clip on the harness will probably snap-off, it's ok just make sure it goes back on snug.