keasa1214

86 Pickup 22RE has new TPS and wont idle unless you pump the gas pedel. it wont reve up over 2500 RPM and YES the TPS has been set. The truck seems like its not geting enough fuel. i used a noid light to see if injectors were working the light was very dim, but did light.

I'm about out of ideas can anyone help?

the_supernerd

I would start by checking fuel pressure, timing, and compression. You can borrow a fuel pressure tester from Autozone and they give you all of your money back when you return it.

keasa1214

Compression is Good, Timing is set to where is should run and idle, and fuel pressure is good. This thing only has 130,000 on it and when in open loop (Cold) it runs fine.

myyota

When was the last time you replaced the fuel filter ?, also check for vacuum leaks at all of the hoses, and check the rubber elbow that connects to the throttle body, they crack from age and heat and that will cause unmetered air to get into the engine.

sam333

How do you know? Did you test the compression , timing and fuel pressure? It runs good in open loop only( unusual) ? How do you know this ? Do you have a scanner or are you backprobing the oxygen sensor?

the_supernerd

I agree that unmetered air will cause problems. Also try cleaning the MAF. Unplugging the o2 sensor will put it in open loop if you want to test it that way.

keasa1214

I vacuum tested it has poor vacuum but it wont run unless you pump the the throttle which can be the result of this. It seems like its miss firing pretty bad when warm. The fuel filter is new and the pump was replaced last year and has plenty of pressure at the rail. The rubber hose at the throttle body is good.

myyota

These trucks don`t have a MAF, the have an AFM = Air Flow Meter, totally different than a MAF.

rube

sounds like either the afm or coolant temp sensor to me. get out the multi-meter and test these.

keasa1214

Its not the temp sensor or the AFM does anyone know how to test a Ignition Module

rube

^^swap it from a buddys truck lol. dont think there is a way to test it, but since you say it runs good cold but not when warm it makes me think it has nothing to do with the ignitor. one thing i would consider looking into is the iac(idle air controll valve). it has coolant running through it to operate it. maybe when it gets warm and opens up it leaks un-metered air?? just a theory lol. you've probably already done this but check the o2 sensor and wiring.
hope this will help you out!

the_supernerd

Unplug the o2 sensor when it is warm and see if it runs better. This will narrow down if it is running better because it is cold or in open loop.

MudSir

I had the same issues with my 91 v6 4runner . I had a bad alternator and a plugged cat. Cleaned the cat and changed the alternator and now it seems fine.