P1251 on 2012 fortuner 3.0 d4d A/t

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Posts: 4
Joined: Sun Feb 16, 2020 2:14 pm
Town: Machadodorp
Vehicle: 2012 fortuner 3.0 d4d
Real Name: Ismai

Hey guys. I have a p1251 dtc on a 2012 fortuner 3 d4d. It's very consistent. If I floor the car even while in park it will go into limp mode at around 4500 rpm or if I'm driving and I floor it n it kicks down hard it will go into limp mode guaranteed. It does not miss it. But if I Rev it gradually no limp mode. As long as u are not hard on the gas the car drives very well.

I have tried a lot to resolve this issue and all has failed :
1) recond the turbo from the car
2) checked egr and intake and it was clean
3) swapped step motor from my hilux
4) swapped maf and map from my hilux
5) swapped turbo drive from another fortuner
6) fitted a whole other turbo with new step motor supposedly better calibrated(not!! Just cond cos I was desperate )
7) tried another turbo drive
8) had it by a very good auto lec to check
9) another accelerator peddle
10) lastly another ecu. Had it cloned and still the same problem.

Now after a lot of research and testing I see that my map sensor reading seems to be the problem. It's not the map sensor or the wiring. It's the ecu.

With the ignition on and engine off any map reading should be around 85kpa(atmospheric pressure) in my area (mpumalanga) . And it is so on my hilux. But the fortuner reads around 185kpa. Even when the engine is running it will also be in the 185kpa region. I think that's where my overboosting issue is coming from.

It's both the original ecu and the second hand cloned ecu that give high map reading. If I plug the ecu into the hilux an turn ignition to on position the hilux also reads 185kpa as map reading. So the issue is definitely on the ecu.

Could it be that the fault was copied while cloning was taking place?

Secondly do u guys think the the map sensor reading would cause my p1251 dtc?

Any assistance would be appreciated.
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