Duramax Throttle Response

Rock Hopper · March 24, 2007

I'm new to the world of diesel trucks. Just got my '06 Duramax Crew (used with 23000 on it). I notice that the throttle response is very slow. If I floor it when I'm cruising down the road it takes forever to take off. Also, I notice when I start from a stop it has a hesitation just after it starts to go. This truck also runs poorly when it's cold which I suspect is normal. Are these other problems inherant with these trucks or do I need to get my truck in to the shop.

I thought maybe the diesel I was buying may have been the problem but I've purchased it at several stations and nothing changes. Any advice would be appreciated.

dogzapper · March 24, 2007

The older generations of the Duramax had varying degrees of "turbo lag" which is why I didn't buy one. Most of the 2006s have the LBZ engine and every LBZ I've driven had no lag at all...the instant response was right there!!!

I would have to think that there is some sort of problem with the truck. Might check the fuel filter and have the selling dealer give it a general going over. Hey, they sold it, they made the money, they should make it right.

My friend, the 2006 LBZ is an absolute animal. When you step on the pedal, it lays you back in the seat and totally hauls asssssss. Something is wrong.

Steve

Shaners · March 24, 2007

My '05 Dmax pulls OK from idle but when it hit's 1800-2200 RPM you'd better hang on! On the road the RPM's are right where you need them, so a little throttle just sets you back in your seat with no downshifting.

When it is cold outside, the Dmax isn't much of a performer until it gets up to operating temps (which could take 10 miles or so).

If the fuel filter has never been changed, then it is likely due to be done. I just had the dealer change mine with just 10K miles on it, but it was the original and was 2 years old. According to the DIC, I copuld have gone another year (5K miles), but I figured I would have it changed.

Since the truck is under warranty, I would ask the dealer about it.

desrtrat · March 25, 2007

i would try running 6-8 oz of LUCAS injector cleaner with about 3/4 tank of fuel. we use it on our diesels at work, we buy it by the gal.@ $30.00 per. or you can try 2 cans of SEAFOAM in 3/4 tank clean up the injectors and see if it helps...

good luck

Rock Hopper · March 26, 2007

Taking it in to the dealer tommorrow to let them check it out. Will update! Hopefully they won't say they cant find anything.

HDdave · March 26, 2007

How bad of a hesitation is there? In my dads d-max, if your driving down the road and just give the throttle a quick punch then let off again the RPM's hardly change. If you just put it to the floor and leave it there, it will take a second to drop a gear or two, and then it will just slam you into the seat. This is on an 03...

Shawn T · March 26, 2007

It's not normal. Temps drop to -40 F here and I have never had a problem with the way my diesels run. These diesel motors are not the dinasaurs of the 80's. That is still a big misconseption. Like Shaners said, change the fuel filter. Also check your air cleaner. Thats what is sounds like to me. Duramaxes hate to be choked. If there is any debree on the air cleaner at all, change it.

repoman · March 26, 2007

my truck is a few years newer and when i step on it it takes off,you can really feel the tourque.i have an appointment weds to have the banks kit installed! i cant wait

chakis24 · March 26, 2007

sorry off topic....^^^^^^^awesome big rig wheels

Rock Hopper · March 30, 2007

Well, here's an update. The service manager at the dealership I went to felt the sluggish flat spot in my throttle. It's very subtle but It feels like the engine is missing a bit and runs rough for just long enough to hesitate just on take off. So, the manager drove it then they kept it for 2 full days. They said they reprogrammed it and checked other computer stuff. The tech also said my 265 tires could cause a problem because they are OVERSIZED. I should have known right there that they didn't fix it and also that the tech smokes crack. The service manager told me he drove it after the fix and it no longer did it.

Now, the truck seems even more sluggish when it's up to speed and it still has the hesitation. I have a feeling this is going to be one of those problems that is never going to be fixed.

My truck seems to run really good whe n cruising along but I'm amazed that at 360hp and 650 ft lbs of torque how slow it is to respond when i stomp on the throttle at about 40mph. Seems like it takes about 2 seconds before it takes off. Unfortunately I have never drove a duramax before so I may be expecting too much.

I will update if I ever figure out the problem. BE ADVISED. Don't hold your breathe....

Shaners · March 30, 2007

Try and find another one to test drive and compare to yours... Hopefully you can find one at a dealer.

I'm running 265's on my Dmax w/no problems...

repoman · March 31, 2007

take a look at the wheels on my truck,think they are a little oversized? well no sluggishness here.if im on the highway it takes a second for the trans to downshift but thats it. oh and by the way,i just got the banks kit installed. HOLLY CRAP THIS THING SCREAMS! i have around 500 hp and just under 1000 ft lbs torque!

superbee · March 31, 2007

That stealer sucks, anytime they mention tire size, NEXT. I'm running 285s and like Repoman said, hesitation is small with or without tune installed. Running rough is not normal.

Rock Hopper · May 16, 2007

My second trip to the dealer and again they found nothing wrong. They gave me a bottle of injector cleaner which I have ran through the engine and it did absolutely nothing.

I took my truck to another Chevy dealer and had their service tech ride around with me. He said that the throttles are sensor controlled and when you push on the gas the sensor can interpret that you want to go faster/slower than you want and it takes it a split second to figure out the correct reading and that can cause the hesitation. He said there was no adjustment and said i had to change the way i drive or deal with it.

I certainly don't hit the gas hard nor do I drive like a granny. I have never heard of this and have never had this problem with any other vehicle I've ever driven.

My luck! This truck is going to have a serious related problem after the warranty is up.

HDdave · May 16, 2007

I don't think I would worry about it if I was you. The hesitation from a dead stop (if your flooring it) could be the torque management kicking in, because I definetly notice it in my dads. His will not spin them from a dead stop, and thats with a hypertech chip, but it will break them lose from around 30 when your rolling. I would suggest finding another truck like yours and taking it for a drive to see how it compares. If it does the same thing, don't worry about it, its just a diesel. You could just be having a hard time adjusting to a diesel, they are very different, I notice it everytime I drive my dad's instead of my 6.0.