2002 FZJ105R - Code 12 and vehicle in limp mode. Idles fine and revs fine in park.

[joshAUST]

Another update.
Turns out I've never replaced the MAP sensor, I just thought I did...
$250 for genuine, wow, no wonder I never changed it.
So I disconnected the vacuum line to it, and sprayed a heap of MAF cleaner in it.
Running techstream, with the engine off, it now reads 99KPA.
It now varies depending on engine speed correctly.
i can now accelerate! Finally.
Thank you all for your help, especially @frawstme

 

[frawstme]

Another update.
Turns out I've never replaced the MAP sensor, I just thought I did...
$250 for genuine, wow, no wonder I never changed it.
So I disconnected the vacuum line to it, and sprayed a heap of MAF cleaner in it.
Running techstream, with the engine off, it now reads 99KPA.
It now varies depending on engine speed correctly.
i can now accelerate! Finally.
Thank you all for your help, especially @frawstme

Glad you got it figured out, although in the end I wasn't much help

I was thinking fuel delivery all the way, if not then possibly exhaust, then electrical. Not sure what lead me to eliminate air early in the process. Well, at least you have techstream up and running now!

 

[joshAUST]

Glad you got it figured out, although in the end I wasn't much help

I was thinking fuel delivery all the way, if not then possibly exhaust, then electrical. Not sure what lead me to eliminate air early in the process. Well, at least you have techstream up and running now!

Thanks @frawstme.
All your advice did actually help... got the wheels turning, and got me to get Techstream up and running, which I am sure I will use from now on more and more.
I also found the TPS sensor was dirty, and another idle resistor sensor thingy was faulty... so the car now runs far better than it did, just running rich at idle until I replace that last sensor.
Thanks once again, I really appreciate it.

 

[joshAUST]

That fixed 58 kPa is the strongest lead so far. On a speed-density 1FZ-FE, MAP should be near atmospheric with the engine off, then drop substantially at a healthy hot idle and change with throttle; a value that never moves points to the sensor signal, 5-V reference/ground, wiring, or the vacuum hose/port—not a fuel filter. Before swapping parts, check that the hose is connected and the port isn’t blocked, back-probe the sensor for a solid reference and ground, and see whether the MAP value changes when you apply vacuum directly. If the original sensor behaves normally, compare the two readings and inspect the connector pins closely. The rich plugs and LPG shutdown fit an over-fueling/incorrect-load signal very well.

Thanks for your advice @lanierchris.
Yes, fortunately, after cleaning the MAP sensor with MAF cleaner, its now reporting correct values.
The TPS also had dirty electrical contacts.
So, with both of them cleaned, the car is now running well.
Its still idles rich, as the PO must have stuffed the variable resistor that adjusts the injector ms value at idle.
I may just replace it with a potentiometer, as a genuine part is ridiculously priced for what it is.