6.5 help

clutch_dust · February 26, 2002

any brave souls with the 6.5 turbo diesels? i have a '94, it's my sole company vehicle and without it, i can't pay my mortgage. thursday i stopped at one of my vendors and when i got back in the truck, it started but seemed to be running rough. got to the driveway to pull out into the street and saw smoke coming from under the dash. grabbed my handy-dandy fire extinguisher (which i always keep on board) and fired away. popped the hood and fired away in there too. still had hot wires and insulation on fire so my only real option was to grab a glove and pull the burning wires apart. man, what a bad day. the 'fire' was contained in the harness between the bulkhead connector by the passenger footwell, through the injection relay/terminal strip and over to the harness junction behind the left valve cover. so i put it in my garage thursday night and start working on it. i have most wires repaired but there were 3-4 wires that the insulation had burned off from the terminal to where the wire broke so i have no way of figuring out which goes where. spliced them together as best i could and truck ran on friday (like s**t), even warm would take 10-15 seconds of cranking to fire, tranny shifted really hard-almost like a shift kit in it (and i didn't put a shift kit in it thursday night!) and this morning wouldn't start at all.

friend of mine at local chevy dealer tried to get me a new harness but says it's on backorder. i tried to find a schematic that would show me the whole harness but not really sure what's going on there. buddy, at dealership, says the harness fire is nothing really new and there is a new harness design because of that and that is why there is a hold up with the new harness.

anybody else run into this type of problem before? oh! BTW, check engine light stays on now so i pulled codes and noticed it doesn't even flash the 12 code like it's supposed to. it just goes straight to problem codes (17, 18 and 35) all of which are injection related. so i figure somewhere along the line a wire from the injection pump to the ecm is still screwed although i have no idea which one. any help you guys can offer will be appreciated and any help that actually fixes this thing is GOLDEN!

SoMnDMAX · February 27, 2002

Well, I hate to say it, but the only way to quickly fix it is to get the schematic and start tracing wires. Most likely you've got something crossed, or the main connector at the firewall isn't making good contact. Either is possible. Also, check your ground straps on the engine to make sure they are still intact.

I personally would replace the harness, both inside the cab and out. Check with another dealer, or have your buddy search the inventory of other dealers thru the computer systems in the parts dept.... I've found parts 100 miles away in stock, when it'd take my dealer a week or so to order it in....

February 27, 2002

have you looked for a complete used harness? There should be some of those trucks around in junkyards.

clutch_dust · February 27, 2002

there is about to be another one in the junkyard soon! i have had about all i can handle with this P.O.S. this is the only chevy that has ever left me on the side of the road. absolute pile of crap.

i think i have the wiring figured out. there is a bulkhead connector that goes through by the passenger footwell with a plastic casing. i didn't really know what i was getting into the other day when i took it apart, i ended up breaking off much of the plastic. i found a couple of my fried wires had gone through this and it appeared to have a resin filler. i was working on it yesterday and it hit me to try my heat gun and it turns out what i thought was resin was hot glue. so once i got the glue out i found two more wires that had burnt through right there. fixed those wires and drove it yesterday and today and no problems that i can see.

may be fixed, may be not. either way, i'm still replacing that harness.