it's really not that serious, just replace the Iac and you are done, the SC4 guys go thru that most of the time.
I wouldn't trade it in and start a car payment because of the Idle Air Control valve, Hell i will give a new TB with IACV on it just replace the whole thing.
If you catch me at the right time i would even install it for you....

 

Believe me, I hate car payments. I already have another one paying for the womans Honda Fit. I've got one good year out of the SC with minimal maintenance so I should be thankful. How much does a new IACV cost? How about the part #?

 

22270 VALVE ASSY, IDLE SPEED CONTROL(FOR THLOTTLE BODY)
Part# 22270-46050 for 2JZGE..JZZ31
Part# 22270-46080 for 2JZGE..JZZ31; CALIFORNIA SPEC

If thats what your looking for and your probably gonna pay about 400$ +
but i wouldnt think that needs to be replaced.. but im not the mechanic working on your car.

 

Depends on the ECU and the SC ECUs are very sensitive. 9 times out of 10 when every someone has come on CL asking for diag help, once the pulled the codes the problem was resolved by replacing a system related to the codes.

 

Almost sounds like the fuel ECU is on the fritz.


It would not hurt to bypass the fuel ecu to see if it makes a difference. You can always connect it back up although to me it seems to be one of the most unreliable parts of the Sc300.

I've bypassed it in 4 different cars now.

 

Before reading your post I was advised the same thing to clean out the control valve with carb cleaner. Upon spraying the valve area, a lot of residue washed off from the area. I ran the car high revs while spraying. Choking the car on a few occasions until I did not see residue wash out from the area.

Now it is wait and see...

 

Car holds a steady 1000 RPM's now. It's strange that the idle has gone from low to a steady high. I'm going to replace the TPS, IACV, and throttle body and see if that fixes it. If that doesn't work then I'll replace the MAF and Fuel ECU.

 

Will find out tomorrow, no worries i will pm you the address.

 

if you take the time to do all that.. are you going to check the codes. see if it tells you anything ??

 

Still haven't pulled any codes have you?

 

i just had a problem like that turned out that when i washed my engine compartment some water got into my cylinders lil compressed air new plugs took care of it did a fuel filter for good measure also car runs like a champ now

 

So I went to autozone to get my codes pulled. They said they only handle OBD2 and told me to try Advance Auto. So I went there and they said the same thing and for me to try Autozone lol.

I found this on amazon and it's only $25 dollars so I'm going to buy it.

 

You get a 2" section of wire and strip both ends.

At the diag port connected to the intake manifold you jump e1 and TE1 and leave the wire there. You turn the key to give the car power but do not start and the codes start flashing or if you dont have any codes it flashes repeatedly.

I wouldn't make this any harder on yourself.

Also out of the things your going to try, bypassing the fuel ecu is the cheapest and easiest option.