ok so i have a 91 with a LSV swapped in. My issue is the idle it WILL NOT IDLE AT ALL. I start the car it turns over and will run (2 secs) but it shuts right off unless i give it gas. As soon as i let off the gas it will stumble and shut off. when the car does idle (foot on gas) it is smooth no missing or anything.

My tps is at .479 at closed throttle and at open i have 4.811.
I have no vac. leaks at all. All extra holes are capped off. (triple checked)
IACV is 100% cleaned out no junk in it.


what could this be. Its really starting to get under my skin that i can not figure this out at all.My buddy who i bought the car off of seems to think IACV.


Id love to maybe get this car running so i can get a dyno graph for it

 

Is there no cel?

 

Base idle screw on the throttle body...possible someone adjusted it, you will need to screw it in and then adjust your TPS again.

 

as stated cel?

 

Fuel pump possibly?

 

that's where I would start as well...im goanna guess before the swap you did not have this issue

 

no cels...ill re-do the tps calibration

 

Do this first.

 

screwed the throttle screw all the way in and re-did my tps calibration. Still not holding a idle. It turns over went to id say 700-900 rpm then shut off. Once i gave it fas it holds but WOT only goes to 3k RPM.

bd tps sensor?? its a 70mm skunk2 tb if that matters

 

i got it to idle after i swapped off my throttle body for another re-did the tps calibration and cleaned out the iacv once agin. Once it got idle 1500 then down to about 900 as soon as i touched the gas it chocked out and died did this 3 times in and row then last time i let it idle and after 3 mins it slowly died off.

 

Do you have a fuel pressure gauge?
If you keep reving it, will it still die after a few minutes?

 

Is your MAP sensor wired correctly? I had this issue on my swap, then I realized the Vacuum line for the MAP sensor was in the wrong spot.

 

no fuel pressure gauge. Im going to find the pin outs for the map and iacv and wire them directly

 

The signal flow for the IACV, as I'm sure you know, or will soon, enters the driver side of the cabin along with the injectors. I believe the IACV signal line hits the main relay and then goes to the ECU. My understanding is once the ignition is engaged the IACV opens, allowing additional air flow for initial start-up. Once engine is running, the ECU takes control.

Again, above is conjecture.

When you say you are going to wire them direct, will you just hard wire it to the ecu harness? Entering the passenger side entry point?