[idskot]

My '91 4.0L has been "bogging down and stalling".

This hasn't happened when I drive, but when my brother (who takes it to work daily). However, he said it bogs down and eventually stalls.

Before, he said he would disconnect & reconnect the spark plug wires and it started. So I replaced the dist cap, rotor & wires. I replaced the plugs back in September & there's less than 4k miles on those plugs.

However, he said that it's happening now and if he doesn't wait a while, he has to give it gas or else it'll die. After a few minutes until it starts up again and runs fine.


I can't replicate it, and I don't know what it could be! Whenever I drive it, it drives wonderfully and I never have any issues. But he said it happens to him a lot.

He drives 30 miles each way to / from work, and I only drive less than 10.

[idskot]

morning bump?

[laybackman]

If I was going to take a complete shot in the dark at your problem based upon miles you both drive I'd say your cat converter is the problem. Has it ever been replaced?
Second possibility is the coil high voltage field is collapsing from being heated up. Start it up then hit the coil with a heat gun. See what it does. If it runs OK take it for a ride as long as your brother does at the speeds he drives! If it dies when you drive that far you can bet it is the cat converter. As time goes on the cat clogs up more and the good running time gets shorter.