Diesel detective.....

unclestripey · Nov 27, 2013

92 Isuzu NPR turbo diesel
Guy takes test drive, comes back in 30 min saying it has no throttle response. Ran fine when he took it, what did he do? He's looking to get it cheap, owner is convinced he's been sabotaged. Ideas?

zukkev · Nov 28, 2013

I have seen rocks get stuck between the throttle linkage and body of the inj. pump causing this very issue...Have also seen it where they shut the key off, and it keeps running, because of a stupid lil pebble! :haha:

unclestripey · Nov 28, 2013

We're looking to buy it at work, seller says the guy drove it off and it came back with no throttle response. Now guy is calling 3 times aday asking to buy it. Seller says he's sure the guy did something and won't sell it to him, truck has a shade over 100k, would be perfect for our company, but I need yo know what to look for when I go check it out.

ceb0217 · Nov 28, 2013

zukkev said:
I have seen rocks get stuck between the throttle linkage and body of the inj. pump causing this very issue...Have also seen it where they shut the key off, and it keeps running, because of a stupid lil pebble! :haha:

lol they will also stay running when the alt goes out. But most likely a fuel filter.I work on and drive these trucks there really simple.theres 1 filter and a water/sedment filter, the water sedment is useally on the left frame rail it has a screen in it you cant see. I have had that screen plug up a few times. Im assuming you did check for a broken throttle cable. And also is it auto or stick.

Edit is it smoking and if so what color

unclestripey · Nov 28, 2013

It's an auto, I go look at it Friday am. Sadly I'm the most mechanically inclined person at my company....I'm pretty good with sawmills, but i really don't know ****.:redneck:

zukkev · Nov 28, 2013

unclestripey said:
It's an auto, I go look at it Friday am. Sadly I'm the most mechanically inclined person at my company....I'm pretty good with sawmills, but i really don't know ****.:redneck:

Wish i had time to come check it out with ya...Seems to me there is an idle validation switch (Basically a throttle position sw.) somewhere near or on the accel pedal, but I am guessing (it's been a few yrs since I've tinkered with 'em.)... But yeah, they are pretty simple rigs. And a tad over 100K is NOTHING for these lil buggers...

unclestripey · Nov 28, 2013

Happy thanksgiving! Isn't everyone up at 4? I wish you could come too! I know all about busy. I suppose if it isn't clanking or smoking whatever's wrong should be a simple fix?:haha: