Just got a 1997 Dodge 1500. Before we bought it, it sat for over 3 months. The few times weve had it go down the road or even down the driveway it will spit, sputter, chug and quit. Its fine when it idels and when its in reverse. Just in drive it will do that. The check engine light flashes and then will sputter and quit. First time we drove it it wouldnt go over 15mph. Second time it ran perfect. Then today while driving down the road it started acting up again. Just put 5gal of new gas and some dry gas in it yesterday. Already has a new cap, plug wires and rotor. Any suggestions?

 

You might have a clogged cat.

 

^+1 on clogged cat.

 

If you haven't checked or fixed the plenum yet (provided it's bad) it would clog the cat over time.

You can physically remove the pre-cat O2 sensor from the pipe, and see if it runs any better on a more consistent basis. It will be louder but who cares....

 

The cat was taken out and punched out then put back on. It cant be that

 

It's possible the pre-cat 02 may not have been re-installed correctly or the 02 is just bad.

Does it misbehave when warmed up or cold?

 

Still doesn't rule out a possibly blown plenum or PCV valve. Need to check its status either way.

 

Its bad when warm or cold. As of now it wont start. It turns over but thats all

 

Its bad warm or cold. As of now it wont start. It turns over but thats all

 

Do you hear the buzz/whir of the fuel pump priming the system when you turn the key on?