Replacement drive by wire system for 2003 Silverado?

ifixedit · July 23, 2015

Anyone know of an EFI system to repalce the trouble prone drive by wire system on a 2003 Silverado with the 6.0 litre? I'd obviously need at a minimum the throttle body, perhaps an intake, new PCM and harness. I checked with Edelbrock, no luck, inquiring with Holley now but no answer yet. Other than the pesky "reduced power mode" problem the truck runs great, don't want to shell out for a new truck right now and I really don't want to sell it just or the reason of the continuous "reduced power mode" issue. I've performed every fix in the book and I've had enough of this crap system! I'd rather spend $2K and make the truck run right vs. a truck dropping off a pallat of payment books!

newdude · July 23, 2015

Reduced power is up, there is a code in the system. Have it scanned and start from there before you throw parts at it.

MikeNH · July 23, 2015

DBW is far from trouble prone. Get it scanned, fix the faulty part(s) and move on. It would be a giant headache.

ifixedit · July 23, 2015

Check here and on the internet, the GM DBW has been a MAJOR issue for many and many have not been able to fix the "reduced power" problem no matter how many dollars spent and how many times they visit the dealer. Scanned it a month ago, got code P1125, replaced the throttle pedal position sensor (for the second time!), ran fine for 3 weeks, now the same code again. I've re-done all the grounds, replaced throttle body 3 times, new TAC module, replaced wiring harness, re-grounded PCM, found a problem with the BCM and fixed, verified the 5 volt reference is correct, new intake gaskets, new knock sensors, new alternator, the list is endless. If you've seen any of my previous posts on this subject, I've about replaced the entire truck which in what I've decided today to do, time for a new one, I'll let someone else try figure it out. I honestly think the PCM has an intermittent issue.

gmtech4 · July 24, 2015

you want to WHAT ??? Lmao !!!!!

00Silverado4x4 · July 24, 2015

I worked on a friend's truck that was the same as yours. It had the similar "Reduced Power" situation. You may have already done this but what I did for him was to completely remove the throttle body and valve covers and all connecting hoses and cleaned out a few pounds of crud. Once I got it back together it ran like a champ and he quit having the problem.

desrtrat · July 24, 2015

my 03 LQ9 original owner, not a bit of trouble..i just do routine cleaning of the TB.

MikeNH · July 24, 2015

Check here and on the internet, the GM DBW has been a MAJOR issue for many and many have not been able to fix the "reduced power" problem no matter how many dollars spent and how many times they visit the dealer. Scanned it a month ago, got code P1125, replaced the throttle pedal position sensor (for the second time!), ran fine for 3 weeks, now the same code again. I've re-done all the grounds, replaced throttle body 3 times, new TAC module, replaced wiring harness, re-grounded PCM, found a problem with the BCM and fixed, verified the 5 volt reference is correct, new intake gaskets, new knock sensors, new alternator, the list is endless. If you've seen any of my previous posts on this subject, I've about replaced the entire truck which in what I've decided today to do, time for a new one, I'll let someone else try figure it out. I honestly think the PCM has an intermittent issue.

Major issue? No. Common? Sure. My 2011 had one of the sensors fail. Drove to the dealer, they fixed it under an extended coverage for the part and off I went. Beyond that I can't say I've heard of any issues. And I've had two GMs with DBW.

ifixedit · July 27, 2015

you want to WHAT ??? Lmao !!!!!

Keep laughing, FAST (Comp cams) has one in the process as we speak, in testing now, so there will be one coming.

And yes, it is a major issue when you read of people spending thousands at the dealer and still no resolve. What else would you call a non driveable vehicle or one that conks out on you 6 times on the way to work on a busy freeway? A good thing?

I've been suspecting the harness from the pedal sensor to the TAC module for awhile even though it seemed to check out fine. Since all the Chevy dealers only want to make you a deal on a "double cab" (I don't want a double cab) and not on a new crew cab, I decided to scrap the new truck idea for now and instead paid a visit to the local junkyard over the weekend. Picked up a complete pedal assembly, harness and all for $30 bucks. Guess, what? Runs like a million bucks! Go figure. Now to see if it stands the test of time. Also found possible water intrusion in the cowl area, some of the seams didn't look to be so hot so gave them a re-caulking with a good urethane sealant. We'll see what happens.