Hesitation

[candiesel]

Hi Guys
Got a 97 K2500 6.5Td with 87000 kms that is doing a lot of hasitation.
I can mostly recognize this at hwy speed's (in overdrive).
I read a lot on 6.5 forums and see that the most common prob. would be the FSD or maybe the pump itself.
However I wasn't so sure because my 6.5 here did not do any type of stalling and starting hasn't been particularly difficult either.
The prev. owner had the injection pump replaced about 25000 Kms ago.
I also had the truck at the local dealer but not much luck there because of no codes.

Any info or previous experiences you wouldn't mind to share be great.

Thanx ahead!

[Tow Master]

Hello and welcome to the forum!!!

Hmm whats it doing when its hesitating? I have 2 6.5's and one of them had a PMD driver that went bad when I was driving it. It would almost feel like someone turned the key off then it would start and move fine again. When I got it back I ordered a new driver installed it and it worked fine since.

[candiesel]

Thanx for the Welcome

Nice Dmax CrewCab there. I have got a small fleet of them at my work and let me tell you these trucks are awesome.
Too bad I can't afford one with low K's.

But ya the 6.5 is doing a very light hasitation ,almost like what the A/C comp. would feel like on a small gas pot when it's cutting in and out.
It is only a light hasitation but it's been getting more costant and I'm woried about the summer road trips ahead.

[Tow Master]

Hmm have you ever replaced the PMD driver? The other things I could think of that would be a simple fix are fuel filter or the in line lift pump located under the drivers seat on the frame.

The major thing it could be is the injection pump itself. Im not 100% sure if there is a way to check that though.

[candiesel]

Hope it isn't the injection pump itself ,it only has 25000kms on it.The fuel filter was done less than 5000kms ago.
My next move was to replace the pmd and remote mount it somewhere of the engine. But still not sure if that is the cause. Most guys get a lot more bad stuff than just hasitation with the failing pmd. Wonder if I can check the output pressure of the lift (transfer) pump.

[Tow Master]

Hmm not sure if you can get a pressure reading from the pump. Mine went bad once but I could only tell when I tried to restart it after I shut it off when it got hot.

[Weasel Diesel]

I'd recheck the timing on the Inj pump to see if it is a touch off.

[dieseltahoe]

the dealer isnt going to find any codes unless the light is on or he drives it and checks for codes while its doing the hestitaion... (at least thats what the shop were i work at said)