Dear All
I am new to this forum and I went through a complete rebuild on my Isuzu Mu
Wizzard, imported from Japan. The 3.1 Turbo diesel (4jg2) blew up.
Head cracked. The decision was to replace it with 4JB2? 2.8 Turbo
diesel. The saga came to completion last weekend. So I thought.
But we do not have expert Isuzu technicians in Botswana, Africa.
The Auto original gearbox do not shift gears at the right refs.
Need to get to 4000+ rpm before it shifts. I am not certain if it
goes into overdrive at all. I will destroy the new engine fast that
way. (less than 500 km on it.) The local guy here can not find the
fault. Apparently the communication is electronic and not
mechanical. The electronic sensor on top of the original diesel
pump was build over to the diesel pump of the 2.8. The question is
where are all the sensors connections, vacuum hose bits etc that it
will need to work, shift correctly. Any suggestions of a good
workshop manual I can import? Help urgently needed.
Changes made:
Different diesel pump
New engine (2.8) sub assembly
Different manifold
Different turbo
The vacuum harness is in a mess.
Electronic harness seems to be O.K.

Thanks

Hopefully some of the members here can be of some help - we've got many expert Isuzu heads as frequent contributors.

But, if not (as most members seem to be from the USA where your engine/truck was not available), try this forum from New Zealand.

TAKE A VERY CLOSE LOOK AT THE OLD INJ PUMP,AND LOOK FOR A TPS SENSOR THAT MAY HAVE A DUAL FEED SET OF WIRES COMING FROM IT , WHAT IS HAPPENING IS THE TRANS IS NOT GETTING AN UPSHIFT SIGNAL FROM THE SENSOR USUALLLY MOUNTED ON THE POINT WHERE THE THROTTLE ATTACHES , EVN THOUGH THE HARNESS MATCHES UP , I BET THE ENG YOU USED CAME FROM A MANUAL TRANS VEH, SAME THING HAPPENS IN THE U.S. THE TPS SENSOR HAS ONE SET OF TERMINALS FOR THE ENG AND ANOTHER SET USUALLY A LONGER STAND ALONE WIRE WITH 3=4 WIRES GOING INTO ANOTHER PART OF THE HARNESS , WITH OUT THIS SIGNAL THE TRANS WILL GO ALL THE WAY TO THE POINT THAT THE ECM WILL OVERIDE THE ABSENT SIGNAL AND MAKE THE TRANS SHIFT RIGHT AROUND 5000 RPM IN A GAS VERSION, AND THE REASON IT IS NOT GOING INTO OVERDRIVE YOU JUST HAVE TO GO A LOT FASTER TO FORCE IT TO MAKE THE SHIFTS, NOT RECCOMMENDED TO DO.. TRACK DOWN THE SENSOR LOCATION A ND MAKE CERTAIN IT IS HOOKED UP CORRECTLY AND I THINK YOU WILL FIND YOUR PROB.. JERRY

Is the TPS sensor the set of wires on top of the diesel pump?
That was build over onto the 2.8
Photo?

I BELIEVE SO , TAKE A LOOK AT THE SENSOR IT IS BLACK PLASTIC AND SORT OF ROUNF AND IS HELD ON WITH TWO SCREWS AND SHOULD HAVE 3-5 WIRES COMING FROM IT .JERRY

Yes it was build over. If I disconnect the plug then the Isuzu goes into limpo mode. Permanent 3rd? Since the sensor is adjustable do you know what the resistance/voltage should be with the throttle completely depressed and completely released? It is going to the Diesel mech tomorrow.
Info on the setting on the pump itself?
At least they are good (from New Zeeland originally!)