I ran into a problem today that I have not found a solution to yet; I did find some similar problems and will try out what I read but still no answer to mine.

I started my truck and it made the sound that it makes as if it was the fuel pump giving out but I am sure it isn't the fuel pump as it would have been my initial thought to the problem. I will check again but I am sure it’s not the fuel pump. Anyways when starting up the truck it sounded that way ( I am using the best way to explain the sound/noise that all of you would be familiar with so you can understand me). I put it in reverse and almost died but I pressed the gas to not allow that to happen. I then put it in drive and it was ok when giving it gas as long as I didn't release the foot off the gas, BUT when I had to come to a complete stop then it died out completely.

I turned it on and since I was trying to avoid the problem again I did something different. When I turned it back on I put it in drive again and instead of pressing on the brake to stop at the red light I switched it to neutral and didn’t press the brake at all just let it keep rolling super slow it was good and didn't turn off.

I did indeed notice that I did use my AC today as it was a hot day today 85 degrees and I never do. As I left that button on is the only thing that was different from any other day that my truck does not give me problems. I turned it off and it seemed to be running good and without wanting to die, as if having the AC on was the cause of the problem.

Has this happened to anybody else? Can the AC affect it that much to the point of killing it? Can it be getting too much gas? Can someone guide me on what else I should check? I am so confused and stressed please any feedback would be gladly appreciated. I will be getting fuel trim averages tonight also maybe that will help me narrow my search.

Thanks!

 

with the a/c off....does the engine start and idle normally ? if so......what happens when you turn on the a/c ( the condenser fans should come on and the idle speed should increase slightly)

You may have a vac leak.....that is a usuall suspect of stalling @ idle speed or when you let off the throttle. Check all the vac lines.....there is also a hidden one on the fuel pressure regulator....if that is broken or cracked.....you can get fuel and idle issues.

 

When was the last time you cleaned your t/body and IAC? Both of these, if dirty will cause idle issues with the a/c on.

 

A big can of carb cleaner can work wonders, and while at it consider clean out of the valve cover PCV vent hoses. On passenger side there is a plastic oil separator that can get gunked up, on the driver side it is just a straight hose to the throttle body, clean out the opening it plugs into as well. The IACV when cleaned should not be "adjusted" , let the computer move the stepper motor. Throttle body is a big butterfly valve, likes to have gunko build up at edges and in a pool just under it.

There is no fuel at this point, so the gunk is from the air cleaner or the PCV system.

Don't use carb cleaner on the MAF, that would need made-for-MFA spray and only when cold. Air filter clean and tight, vac hoses in good shape. You'll have it purring like a kitten.

 

@ XCELLER8 yes the engine starts and idles normally. But if I turn on the AC it drops the idle speed and starts to sound as if it is flooding.

@ Disco Mike I did that less than 10 months ago.

@ Savannah Buzz I will go get what I need today and try to resolve my issue asap.

Also just another piece of information according to the ECM my MAF isn't registering at all so the truck is running off the VE table.

 

Well it should show something, and it should change. Without the MAF the ECU has a hard time guessing how much air is being mixed with the fuel. Might examine and clean connector for MAF cable.

 

The MAF ins't reading the air flow but isn't completely dead so its not giving me a code either.

Here are some pictures taken from the test drive today.