My isuzu ftr34 dpd light is on but it won't start regen. rpm goes up to 7000 & stuck there for a long time

Nothing major remove all parts and fittings around regeneration sensor
There are two holes under regeneration sensor
They are clogged
Clean all the way to exhaust
This will solve your problem

like all cars with OBD any year.
this means.
to scan the PCM (or ecu)
scan it , the lamp means you have DTCs or smog failure.
some cars hide DTC errors an no lamp.
so scan it anywhy and win/
the errors are presented as DTC errors. codes.

all 2005 here in uSA scan,

get is serviced.
or read the FSM on car.
2 choices.

or
Diesel Particulate Filter
needs attention. "serviced"

call douggy from trucktech he can bypass the system

TRy replacing the idle air control valve

Dpd light on and check engine light on

please keep me posted as well, ALL my gauges are doing the same. First the gas, filled it one day and it fell all the way and light turned on, then my themostat, freaked me out, thought i was overheating,...NO just the guage, NOW my spedometer is stuck on 120, and my RPM's are acting crazy. i have read tons with this same problem, WHY WONT the manufacturer DO SOMTHING??

Hello, try and turn the ignition slowly like you are going to start the engine. There is a very small "dead" space where you will see your gauge lights go off.

What you want to do is cycle the ignition switch from off to that dead space. Each time you do it your stuck speedometer will move towards zero about 10 mph. So if its stuck on 40 you will have to cycle it at least 4 times.

At first you will probably actually hit the ignition and the engine will try to start.....just release it and try it again.

Thanks

are you checking code with a small simple scanner this will not always work, a larger more sophisticated unit may find code or runs codes at over 2500 rpms when light comes on

It may have a faulty cluster. Or possibly could have a charging system problem.
Take it to a dealer and have it scanned for codes.
The instument cluster is a module that can store trouble codes. If the cluster is at fault the new one will have to be programmed to the vehicle to work correctly.