I have a 2002 Grand Caravan that "sputters" for lack of another term, when passing or accelerating. I can "creep" up to speed, but if I stand on it to pass it chokes! I have had the throttle body cleaned, new fuel filter, air filter, plugs and wires. I still does it. Also, put a new catalytic converter on it. I does not throw any codes!!!

Any ideas of what else I can check as whatever it is seems to be killing my gas mileage too.

Thanks all,

 

Try a bottle or two of water out, HEET, Dry Gas, in the tank, if you have any condensation in the tank/fuel it will react the way you describe. May not work, but it is a cheap fix if it does.

 

This has been happening for about six months. Do you think condensation would be in there for that long. I know it's still a cheap thing to try, but just wondering if you get condensation in there does it remain in there?

Thanks for the reply

 

Well, condensation becomes water in the gas and water will not burn, so until all of the contaminated fule is passed, you still have water issues. The additive (iso-propyl alcohol) just homogenizes the water and allows it to be burnt.

 

stikrz, you've done the "standard" stuff I'd recommend ... any chance this is a tranny issue?

 

Beats me. It seems to shift fine. I wonder if it's in the fuel delivery system somehow. Pressure drop or something, but I don't know how to check that. Sure is frustrating.

Thanks for the thought

 

If there's no Check engine light, I would first check fuel pressure. If you are at idle in park, and give it gas can you duplicate the condition, or does it only do it under load?

 

Only under a load mostly.

Thanks

 

I didn't mention before, but sometimes it won't start without pumping the gas a couple times. Not sure what that means either.

 

You can plumb in a fuel presure guage at the schraeder valve (the one that looks like a tire valve) and,using a long enough hose,bring the guage inside the van with you and go for a drive.
If you can duplicate the problem every time the fault should be easy to find.

A drop in fuel pressure can be from,
1.The fuel pump is dying.Sudden acceleration needs more fuel pressure than holding a steady speed or "creeping" up to highway speed.

2.A bad coil.The ignition coils can fail and still allow the engine to run they just can't give the jolt needed to overcome the extra cylinder pressure under hard acceleration.This should throw a code however.

3.The emmissions control system could've flipped out.This should also set a code.

Another place to look is here;
http://www.allpar.com/