I posted a portion of this on another thread, and realized I needed to provide more details and start a new thread. Forgive the sins of a newbie.

I am having overheating issues with my LB7 when towing heavy loads uphill. This is a 2002 GMC 2500HD Crew Cab short bed. I had the classic fuel injector failure at about 97k miles, replaced under GM warranty. The truck now has 183k miles and has shown extreme loss of power (when hauling) and engine overheating as described for the last 20k miles or so. Like Oilfield Mafia, I'm towing a large, heavy RV in and out of the oilfield, around 400 miles a month or so.

My local Duramax 'expert' can only tell me that this shouldn't be happening, and offers no solutions.

I have periodically used an OBDII Scanner to scan for codes, but haven't noticed any after episodes of power loss or engine overheating.

I contacted Banks Power a couple of weeks ago and they immediately pointed to the wastegate actuator as the problem, and recommended the Big Head along with the Econo-mind Diesel Tuner. After due consideration, I decided to go with the Big Hoss package (single exhaust)...this arrived in 2 shipments. First shipment consisted of the Big Head, Ram-air Intake, and 6 Gun Tuner, which we promptly installed last Friday. I drove home unloaded from Tulsa to OKC after installation, with tuner in stock mode. There is a very noticeable increase in power when driving as a passenger vehicle, which I attribute to the Big Head.

On Saturday, I got under my 36' 2000 King of the Road and pulled it out to the Panhandle. I used the tuner's power level 4 for this. Shifting was fine, nothing rough or jerky. I was duely impressed with the power the truck exhibited in towing, but I continue to have overheating issues on hills of any duration. I pulled over to let things cool down each time this happened, then rolled on. At one point, I blew the driver's side of the turbo hose off the elbow going into the intercooler...no damage and was able to put the clamp back on and continue.

I checked and cleared codes each time I pulled over to cool down. I didn't record them, but there were a fair number of fuel rail pressure codes encountered. I'm wondering if this might be the source of the overheating issues? Addendum: I just checked the Banks IQ and found my last codes still in place. They are: P0234 Engine Overboost Condition, P0540 ECM detects voltage on the IAH circuit when the relay is commanded OFF, or incorrect voltage when the relay is commanded ON, P1093 Fuel Rail Pressure Low During Power Enrichment, P1094 Fuel Rail Pressure Low During Idle or Decel Fuel Cut-Off (DFCO).

We'll finish out here later in the week, with any luck, then its a downhill tow back to OKC, presumably in cooler weather. Time permitting, I'll drive to Tulsa unloaded and we'll install the Monster Exhaust and Intercooler. I'm beginning to suspect I will still have overheating issues.

I wonder if the P1093/1094 codes are a result of running the 6 Gun Tuner in a mode other than stock? Given the dusty roads I drive, I change the fuel filter every 15k miles or sooner. I am due for a filter change very soon. Are there diagnostics I can perform?

Can anyone point me to more information on this? Advice on Duramax expertise in the central Oklahoma area, or direct experience with this issue would be much appreciated!

regards,
Bluze

 

Try porting the intake horn

 

The Banks Ram-Air Intake System, to my surprise, did not come with a horn. Its a separate purchase. It is a larger air box than stock, and a horn can be added to it.

--Bluze

 

You might wanna try getting those