On saturday the speedo stopped working, then i noticed the overhead console temperature display wasn't right and when i was coming to a stop the ABS would kick in. On sunday the 4wd was slow at shifting. On tuesday it started hard and the transmission took a long time to shift into the next gear. 0n wednesday the brake light on the dash came on, and i had to boost the truck to get it going and now it won't idle. And by the way i changed the speed sensor, it didn't help. Now tell me where to start.

 

Welcome to the forum.
It sounds like a pcm malfunction. Prehaps try unhooking tha battery for about 1/2hr to reset it and see what happens.

 

Welcome to DF +1 lxman1

 

Well, today the battery is dead. Put in a new battery, started it up and now the ABS light is on. But it will idle now. I think i have a common ground bad or maybe a harness connection corroded. I'm going to start with the speedo wires, since that's where the trouble began. And i did leave the battery diconnected for an hour, nothings changed.

 

Disco the battery, then step on the brake pedal to "bleed" out any add'l current that may be stored anywhere within the electrical system.

Go eat lunch, etc, then come back, connect the battery, turn on truck, let idle for about 5 min, then without turning truck off, drive around for about half an hour. Do some stop and go, low speed, make a couple of three point turns, then get on the freeway, drive a few miles at freeway speeds, etc. Basically, do lots of varied driving and let everything get fully warmed up.

This way, the computer is "reset" then gets to "relearn" everything. Hopefully, that will help, if not, good luck, electrical problems are the worst!

 

You wouldn't believe this, but i found the problem with my truck. The ABS module has a 14 pin connector on it and it was corroded. Cleaned the corrosion and the truck works perfect again.

 

Glad to hear its back to normal... what year is it by the way...

 

2002 quad cab 4x4 SLT sport 360,20" wheels, Dynomax 3" single catback, K&N air filter