Okay SO last night I was driving around and the car was fine, I went over a set of railroad tracks that were kinda bad and then the car started to hesitate/bog under 2000rpm. So I got to my GF's then this morning the same thing i get down the road tag the gas and it sputtered. It was fine the rest of the way home (15min) but i was very gental on the gas.

Now I hooked my datamaster up and drove the car around and sometimes my car stumbles when slowing down. It dropped to 450rpm but figured itself out and through the code.

My readings were.

before the error...

1050rpm....map 62.0KPa
700rpm.....map 80.8KPa
450rpm.....map 91.5KPa
725rpm.....map 83KPa <-----this is where it through the code.

Also I have 5 volts from the tan wire...dont get any reading on the green wire.

It also just went into closed loop like 5-10 seconds before it did this.

I have always had the irratic idle thing from time to time and never code this code. Also when it started doing this today and last night i wasnt messing up at idle when it started.

Jay

 

Im gonna try cleaning the MAF, reseting the IAC (i just swapped it also for another used one and at the same time cleaned the entire TB).

Also I am gonna try adjusting the idle and TPS voltage. I am reading .90volts TPS at Idle. So I am gonna slot it and try to get it down to 0.67V and try to steady out the stumble in the idle while braking. My buddy that built the motor said he had this issue and it was because it stumbled at idle and set the code off. SO maybe I will try this and see. Also I have my other buddy loaning me a MAP just incase.

Jay

 

Check the connector for the MAP sensor. They dry out and crumble, giving you erratic MAP readings. Sounds like the green wire may be shorting to the gray reference voltage wire (is yours tan?). The code sets when the MAP goes over 68kPa (~3.0V) when throttle is 4% or less. Did you try unplugging the MAP sensor when it was idling erraticly?

You should be seeing about 3V between the green wire and the black wire with MAP readings like that. The factory wiring diagrams show the reference voltage (5V) source wire as gray.

 

it may be grey, the wire is dirty looking. Also it has some oil build up on it when I took it out. I go 5V on the green and black wire. The car only stumbles when braking at a light never really stumbles just sitting there.

I didnt get any voltage with the key on from the black wire to the middle wire(tan or grey one) These were all messured from the pins with the MAP unplugged.

Jay