Been busy got hired lubetech recently and going school with 16 units. I cleaned the IAC really good. replace the damn IAC bolts with a needle nose locking plier i borrowed from my friend. I had to clamp that damn plier extra hard and it finally worked. So after cleaning it and putting it back together, nothing has changed.
However, I picked up some new codes. I haven't pulled codes from the car since last time i picked up the po171.
Here are my new codes
P0100 MAF or VAF A circuit malfunction
P0110 IAT sensor malfunction
and i still have P0171
my oxygen sensor mon, catalyst sensor mon, and evap system monitor read INC on my code reader.
I don't know where to start. I just now know it wasn't a dirty IAC. I'll continue to update and post what worked or didn't work.
looks like it might be the MAF
I will test it on wednesday, then replace it if I have to. Damn thing is expensive. 150 for goddamn autozone
3/28/12 update. just writing here so I don't keep double posting.
Wow I'm so stupid. So I checked toyota procedures through my auto school. ( I wont say which school so I don't give them a bad name or anything haha). The procedures say to check intake air temperature and see what the temperature is. If it is -40c that means there is a open somewhere and the sensor itself is good. If it is 140c or above there is a short somewhere and the MAF is also good. If the reading is anywhere between, the MAF is bad because the CEL is on with the p0110 code. Normally you would want the temperature in between if there is no code and everything would be good. Because there was a code the MAF would be faulty if it fell in the normal temp range. So I used the scan tool and I found the intake air temperature to be 92F. So I was like damn my MAF is bad it cost $175 for a reman. I double checked the IAT harness wire voltage and it was in range. I read 1.8x volts which was in range of spec. I think spec is .5v-3.5v
Before I get into anything else. Remember on 3/24/12 I cleaned the IAC and pulled codes after cleaning it because idle was still bad. That was the first time I ever saw the p0110 and p0100. The p0171 I had for a while.
Fast forward back to today. Before I went to buy the damn MAF, my instructor asked me if I ever disconnected the MAF because just by disconnecting it while the battery is connected, it trips the CEL to come on. I told him no because I remember resetting the ECU the last time I took it off to clean it. I completely forgot that while I was cleaning the IAC, I had the remove the connector and push the rubber intake hose down, to take off the metal intake pipe, to get to the IAC/throttle body. I mean you don't have to do it this way but I found this way easier.
Basically I set the codes myself by unplugging the MAF without disconnecting the neg cable. Now I am stuck with a reman MAF after letting my perfectly fine OEM MAF go, down $175 dollars, and back to square one. I hate myself right now. Firstly, I should've remember I disconnected the MAF few days ago cleaning the IAC. Secondly, I should've tested the MAF off the car. I just wanted to use the scantool because it was slightly easier to do that. O well... I'll just think of it as a valuable learning experience.
So I only have 1 code that is haunting me, p0171.
I am going to check out the fuel system next.
I didn't check out the fuel system after talking it over with a friend. I decided to hook up my code reader one last time. I picked up p0171 p0300, p0304 this time. My friend advised me to shoot some carb cleaner to see if I can find a vacuum leak. I was lazy all this time to diagnose it further, not really, just tired to. Today after work I decided to try finding the leak with some MAF cleaner. that was easy less than 10 sec found a leak at the intake manifold gasket. I guess I gotta get another new one again. I'm short on cash maybe i'll go felpro this time.
lol damn I just realized the first reply to this thread was the answer! haha