What does "NPR" stand for in the Isuzu NPR brand?
The Isuzu N-Series is a range of light/medium duty cab over trucks. These trucks were quite popular in urban areas because of their shorter wheelbase and greater maneuverability. The Isuzu N-Series is divided into NPR, NRR, and NQR models. The second letter refers to weight rating. The letters H and K are used for regular cab, M for the High Cab, and P, Q, and R for the Wide Cab model. In the examples, the third letter (R) means rear-wheel drive.
Why doesn't the transmission in my truck work? And my Isuzu NPR-HD has no acceleration! Please help!
Sounds like you need to change transmission fluid and filter. Buy some synthetic AF fluid because, regardless of cost, they will do the job. Also make sure to change out the transmission filter.
And with regards to your acceleration, check the operation of the vehicle's waste gate actuator. These sometimes can get corroded to the point of being unable to move. The engine would start and idle, but not capable of revving when the gas pedal is depressed.
My truck is in the shop right now—I'm having the fuel tank replaced. The tank rusts and clogs up the fuel system. This appears to be a common problem. What should I do?
If you're convinced that you have fuel-related problem, replacing the fuel tank with new one isn't likely to be a solution. In time, the problem would repeat itself. You may have to invest in an aluminum or plastic tank.
Should you have to replace the tank, you must blow of all dirt from the lines with pressured air. While one person blows the tank, another has to push the fuel plunger up and down to make sure no rust or dirt remains in the lines.
How do you prime a diesel fuel system in an NPR?
Normally, the primer is on the filter and bleed screw. Normally all you need is to fill the fuel filter with clean diesel, then fit and prime. If you're having real difficulty, you could simply open pipes going to injectors and turn over until you see the diesel coming from pipes, but a simple prime should get it started.
My NPR's brake switch is not working. I checked the fuse and it's working fine. What should I do? Also, my NPR's transmission will not engage in drive or second. If put in 1st gear position, the truck will drive as it is supposed to. Once it is going I can shift to Drive and it works fine until I have to stop. Now I have to shift back to 1st gear position to get it going again. No lights or indicators are going off. What is wrong here?
A bad wire or connector may be the culprit. Inspect the engine from switch to power source using a voltmeter. The exact point that goes from 0v to 12v (key on, brakes on) is the point of failure. Check voltage at each point and you will find your answer. It's merely series circuits, which are no more complex than a flashlight.
As for your vehicle's transmission, sounds like you need to replace the vehicle's transmission fluid and filter. Any kind of synthetic AF fluid available should do the job. Also, make sure to change the transmission filter as well.