as far as i know the cat is original. ive already gave it a full tuneup including fuel filter and air filter. the pre cat sensor was done by dealer, no telling who done post cat.
truck has its own mind when it wants to run poor, somedays it runs poor when just cranking up and some days when its warmed up, im begining to think it has pms or something

 

get under there and follow the 02 wires back to where they are spliced in and make sure there is a good connection with nothing obviously wrong. if they were replaced with universal sensors then some cutting and splicing happened, and could be some shotty work-bad shrink tubing or a crappy harness. thats the cheapest easiest thing to rule out.

 

thanks for the info, will look at that also. do have a 02 sensor on order from dealer and will be in tommorow. go figure they dont have one in stock because theyve sell alot of them

 

well, looks like off to the dealer we go. checked all wireing from sensors to pcm, no breaks,freys or meltdowns. both sensors new from dealer and now getting codes for both sensors, has no smoke from exhaust, plugs were very clean so doesnt look like plenum so what the h***! anyway ill keep you posted what they find and hopefully one day someone can benifit from the info.
by the way, thanks to everyone for giving me direction and trying to help solve my problem. love the site and recomend it to all my frends with mopars

later "sweeper" (jeff)

 

sorry it didn't work out. good luck with the shop and come back with the answer.

 

oh yea defenately. hope they wont get me to bad

 

ok, took truck to dealer finally. the said the pcm needs to be replaced, said it has short to voltage problem. my next question is could i get a used one and it work or would i need to get it programed or would it be best just to go ahead and bite the bullit and pay them $800

 

a few thoughts.

IF, and that's a big IF its the pcm, then you can get a refurbished/guaranteed one from a lot of places, including autozone, and internet. they run 250-350 or so. if you do that, search for pricing and warranty and reviews. pcfixer had a bad experience with somebody, but i don't remember who.
http://www.autocomputerexchange.com/...Pickups/2001/1

^ the refurbishers will flash the pcm with your VIN number, mileage, proper options? which is real important to california and some other states with complicated emissions testing.

another option is to get a used one from a junk yard or ebay. if you go this route, be sure its the right year, engine, trans, etc, or nothing will work right.

the big IF, is IF a pcm is going to fix your problem or not. it would be very reassuring to borrow one from someone else's 2000 5.9 to see if it really fixes your problem or not. if you could find a really cheap one in the junkyard it would be a no brainer to buy it as a test unit, even if you didn't use it long term. you might could even send a junkyard pcm to the refurb'er for flash only for reasonable bucks.

 

thank you for this info, the link you gave me is probably the way im going to go. the dealer is only going to give a year warranty so is the auto computer exchange at a 3rd of the cost.
hopefully will order by the of the week and ill let you know how it turns out.
again thanks
sweeper (jeff)

 

just beware - i've read a lot of posts on here over the years that start out like this....

i had some problem and took my truck to the dealer. they said the pcm was bad and replaced it for $1000. that didn't fix the problem. so the the dealer said the cluster was also bad but it didn't originally test bad because of the bad pcm (BS) so they replaced it for another $1000. that didn't fix it either. i'm sick of this truck what should i do. edit 2 weeks later- i took my truck to my cousin fred who found a loose wire and plugged it back in. problem solved.