I re-installed my quad xzt box two days ago. Yesterday I thought I noticed a little more injector rattle. This morning when I left for work my truck started bucking and farting and burping black smoke under acceleration around 2k rpm. I stopped on the side of the road and pulled the box off and used the by - pass plug it came with, so I could leave the harness there. I called the delaer while I was driving and asked them to ready the diesel tech who recently replaced my #6 injector. They informed me he was no longer there[:@], and it would be the end of next week before they could look at it because the only diesel tech there was booked through then [:@][:@]. So I continued on with my day and it smoothed out after a while. On the last leg of my trip today I stopped and had my bed rail protectors replaced. When I left there to come home it started acting up again and threw a CEL. I got home and did the key trick and the codes I got were P0148 (HPCR Checksum) and P0193 ( Fuel pressure sensor voltage too high). Now the quad harness plugs into the rail pressure sensor, so I took the harness off. Then I drained my fuel bowl just to make sure I didn't get some watery fuel, it was pristine.I just returned from a test drive and it seems ok now. Should I jsut go to an auto parts store and have them clear the codes? Will the dealer be able to tell I have done this? Should I just go to another dealer and let them check it out?

 

I would get ahold of quad himself. . .it sounds like you have a bad harness. he is VERY good about diagnosing if it is his harness that has a bad diode or not.

 

What about the truck? SHould I clear the codes? I hate seeing that CEL while I'm driving.

 

I would say remove the harness completely, then go on a test run and see if she acts up. it wouldnt hurt to have the codes cleard out.

 

A good tech will know exactly what caused this. The problem is in the first line of your post.The dealer will be able to tell what the cause was even if you take it all off before you go in.

 

Drew, I took the harness completely off and test drove it. It seems like the symptoms are gone now. I guess I'll hit the Advanced Auto parts tomorrow and ask them to clear the codes.

 

I don't know the Quad well but, isn't it a pressure box ? There could be something wrong with it or it's harness but, the only real reason you'd get the P0193 code is if you spiked the rail pressure. It must have gotten up to or close to 26 to 28K

The fuel delivery malfuction is a common code and may just go away. Sometimes if the ECM senses a problem in one area... it inadvertanly affect other things.

The dealer will put you in the system as a NON warranty if you go to them with this problem than, you'll be screwed down the road for other things.

 

The quad box I have is just a 60 hp econo box. I don't think it actually spiked the rail pressure. I didn't get the cel or code until I pulled the box and left the harness. I am gonna try to have those codes cleared and see what happens. Does anyone know if clearing those codes at the auto parts store is final, or does the computer save a list of codes that were there and then cleared?

 

the codes will erase but, ( and I may not have the wording correct ) it could have changed the "check key sums" count. That's what the dealer can see. That's one thing the Smarty doesn't do which is why I think they can claim it's not traceable. You really ought to think about getting one. You an clear your own codes, change the ABS setting for tire size, get a crap load of power and be safe going back to the dealer.... that is unless you really break something.

 

that is why I say it may be the harness. even though it did buck a little with the box on, it was able to keep things under controll due to an issue with the harness. with the plugs in the computer was having to go through the harness and noticed something was amiss and threw the code.

I believe the econo boxes from quad are pressure timeing boxes.