Can you give me a brief explanation of how to clean the IAC please? Its on the throttle body correct? If i drive the truck in to autozone will they be able to test the icm or will i have to remove it and bring it in?

 

You have to remove the ICM and take it in. They can bench test it for you.

Correct the IAC is bolted to right side of the throttle body. Take it off and use carb cleaner to clean all the carbon out of it. Pretty easy to do and does not take long.

 

Ok so far i was able to get the ICM tested tonight and picked up a new IAC gasket and some carb cleaner. The ICM tested negative for any problems so I guess thats not the problem. Tomorrow morning i will get up early and clean the IAC real well and see if that fixes it. I was able to get the truck started a few times today. It runs good when going down the road. The idle is definitely rough though. It still starts pretty good when its warm or has been run in the last two to three hours. I will also try the fuel pressure test again tomorrow. Hopefully I'm doing that right. I have just been screwing the gauge onto the shrader valve and have someone turn over the engine. should i disconnect the wire to the coil so it doesnt fire? And when i tested it the gauge read 30 lbs but it took 2 seconds for the needle to get to 30 lbs. is the needle supposed to shoot up to the measured reading or does it normally rise steadily?

 

Supposed to go to between 28-45 immediately. It is probably the pump on the rail.

 

Ok I just did the pressure test and it again took 2 seconds to make its way up to 30 lbs. My next question is where is the fuel pump on the rail that you are talking about? I thought we only had the fuel pump in our tank. Are you talking about the fuel pressure regulator? I was hoping that since it does build enough pressure that maybe its just the fuel pressure regulator not letting the pressure build quickly. Thanks for all this help

 

What about the tfi control module? I think the icm is the same thing. People all call it something different.

 

TFI = ICM yes you are correct there Big. The pumps in the tank are low pressure pumps. They feed the pump on the fuel rail. It is on the driver side of the fender and should have a metal shroud over it. That is the high pressure pump that takes the fuel and gives it to you at 28-45 psi.

 

Is there a way to test the solenoid on the IAC? If i have to get a new high pressure pump are there any brands to stay away from or to look for? There's a pretty strong gas smell when i try starting it a couple times. The truck has started sputtering a lot when driving in town at low speeds and low rpms. runs great on the highway

 

The best way to test the IAC is start the truck and then unplug it. If it stalls or runs worse, then the IAC is probably working. If it doesn't make a difference, then its bad.

 

FIRST OFF!!!!!

you only have the pumps in the tanks not on the frame rails. 92-96 had intank pumps only.

second plug the pressure tester in bleed the pressure then turn the key on and off a few times, but dont start the truck. it will build pressure then go inside and come back out about an hour later and look at the gauge, it should still be holding pretty steady.***if it dropped dramaticaly your going to need a new pump****

start the truck, and watch the gauge, rev up the motor the pressure should fluctuate some. (((my 4.9l raises when you rev it)))