No power - especially on hills

[65-f100]

Need some help here. 96 K2500 Suburban - approx. 181,000 miles. Bought at a little over 170K so not sure what all has been done previously. I've installed the Turbo Master and relocated the FSD. Other than Amsoil in the engine - all else is stock.

When traveling to NC mountains this past weekend - the truck just had no power going up the hills. There was one grade - maybe 6-7% for a mile or so - I was barely able to maintain 50 mph. This is without towing anything except the family. It downshifted to 3rd - rpms went up and the mph came down. I was getting no black smoke or anything - boost gauge was reading right at 7 psi. Don't have the EGT installed yet so not sure what was going on there. Engine Temp went from around 185 to 210 until I reached level ground again.

Questions - I have no idea if/when the injectors have been replaced. Should I start here? I also plan on an exhaust system and Heaths new reflash for the ECM. I know these will help. I just can't believe this is normal - maybe a clogged Catalytic converter?

Just looking for any thoughts - it runs so good otherwise. Thanks!

[Billman]

Clogged 'Cat' is a very good possibility.

Check Air & Fuel filters too.

I would definately start with the exhaust. Who's you use is your decision.

[65-f100]

Air filter and fuel filter have been replaced. I've spoken to my local exhaust shop and he can make me a 3.5" system cheaper than I can buy one and install it. That will come soon

[john8662]

Most exhaust shops don't make the type of exhaust you really want. You will want a Mandrel bent system, this is a bending technique that allows for bends that maintain the pipe Inside Diameter. Most bending tools crimp the pipe or crush bend that restricts the flow. The better flow, the better performance you'll see.

My guess would be the injectors. My rig behaves the same way on big hills, but I don't have exhaust installed (yet) and have the same old injectors installed. The suburban is sitting in my shop now till I get my exhaust installed. I just installed new injectors, but can't drive it till I get the exhaust back on, so when I get it back together I'll know if the injectors helped.

[65-f100]

I'll be interested to see what difference your injectors make. The exhaust shop is doing mandrel bends. They do a lot of custom race exhausts so they know what they're doing.

[Marty Lau]

Make sure you replace the down pipe that has a built in dents and scrunches that restrict up to 45% of flow.

[65-f100]

Yes - I'm planning on replacing everything from the turbo back

[autocrosser]

If your cat were plugged you would be pumping out lots of black smoke and the temp would probably rise if pushing it hard. this is from past experience on my sons truck and a couple others that have had the problem.

Sounds like you were maybe on I40 around Ashville area going up the black mountain hill. It's pretty steep. Before some mods my truck would only make 25mph pulling a 8k trailer. It will hit 45 now with just exhaust and boost increase.

[65-f100]

Autocrosser - I was actually on 1-26 going towards Asheville - the Saluda grade. If I were towing something, I wouldn't be as concerned - but I had nothing but the family in it.

If the Cat were plugged - wouldn't that prevent exhaust flow and hence prevent black smoke?

[charliepeterson]

I believe after 75,000 miles the injectors don't owe you anything! Sure, some people get lots more out of them but they don't atomize as well. I'm running the "high Flow high pop" and love them!!

The lift pump is VERY important. The injection pump needs all the fuel it can get from the tank without working too hard. The extra fuel also keeps the injection pump from overheating as well.

Heat kills this truck!
Opening the exhaust front to back is very smart. I think with a little work you can go back to this hill and eat it up.