ROugh IDLE 97' 3.1

[RussTad]

Ok so the other day my car goes totally out on me. This right before it died it started to run really rough.

Here was the "problem" The gasket was leaking into the engine and my radiator fluid was being consumed like nothing else. It was also leaking.
So on sunday it totally dies on me.

This is what was replaced.

Plugs, wires, intake gasket, valve cover gasket, pleman gasket, oil change, oil ring (drive) and 1 coil pack.

So the guy did all of this and it has a really rough idle. HE tells me it is the main air flow sensor and he left that unplugged and that I need to pick up one at a junk yard. The check engine light is solid. He put it on the computer and no codes were comming up. SO he thought it was the main air flow. I plugged it back in and ran around with it for a little bit it seemed to have a little bit better of an idle with it plugged in. Also my fuel is fluxiating I have about half a tank but sometimes when I accelerate it goes to 1/4 or even less. What could be the cause of this rough idle? and what are some things I can do to fix it.

[75Trump]

I had the same thing happen to my '95 3100 and it turned out to be the fuel pump.
Right after start up, the car felt sluggish and after holding the pedal to the metal it would seem to clear itself up. But after stopping very rough idle and hard to get going again.

I checked the "sound" of the fuel pump as the Haynes book says to do by shorting the test pin to the 12v remote terminal. I could hear the relay click but, could not hear the pump running.

It was not fun removing the tank or the fuel from it( my son had filled it the day before!). To my surprise, When I disconnected the line from the tank to the fuel filter, I could then get the pump to run enough to fill the gas cans I used to drain the tank. Wow... the pump was barely pumping.

When I finally got the new pump and screen in the tank and reinstalled, I began to refill the car and just for giggles, made the pump drain into a can again. What a difference. The fuel stream was very strong.

I'm not saying it couldn't be something as simple as a clogged fuel filter, but mine was the pump. Good luck.......75Trump

[spence78]

On my 91 my car died and then started back up ran fine for like 30 sec, then died again ,I started it back up and ran like it was a old V8 with incorect timing I had to floor it or continually pump the gas to keep it running it died again and wouldn't start again. I scaned it with a $10,000 snap-on tools computer and there wern't any codes so I poped the hood and locaed the valve on the fuel rail which looks like a valve for a tire and checked for pressure while cranking over the motor and there was none because the fuel pump was shot. I put one in from a wrecker at the cost $150 CAN. I like you also had my coil pack replaced not even a weak before and I also had just put in a brand new battery the day my pump died.

[F1 Ape]

Got a similar problem, goes through coolant like crazy, rough idle, then clears when u step on it.

also, could the bad fuel pump drain the battery?