Hi there,
I have owned my T4 van for about a year, it is an AAB powered non-turbo diesel variant, which I have converted into a camper.
Unfortunately the engine dropped a valve at the end of August, and rather than rebuild and still have a sluggish van, I thought I would try and get the D5252T engine from the Volvo V70 into the van instead. Not chasing power, just wanted something that would pull nicely joining motorways, up hills etc.
Current spec is:
D5252T engine, injectors, fuel pump, turbo,boost solenoid, EGR blanked off
VW ACV wiring loom, throttle pedal,MAF, MAP, Crank sensor, and what I believe to be an 88hp ECU that has had the Immo removed. ECU number is 074906018AK.

I managed to get the engine running without the intercooler connected, so just drawing in air from the Volvo inlet manifold.
The idle was very lumpy, but it ran, and was responsive to the throttle, as shown in the video here:

Knowing what I know now, checking the timing within VAGCOM and setting the Injected Quantity to around 3-4 would have probably got it idling nicely.

But alas, I thought as this engine in stock form is 140hp, that a standard ACV map would be closer to what I need out of the box, and found two standard ACV maps on ecuedit.com.

This is where the trouble started! I cannot remember if it was after flashing the ecu with the first or second map, but when I fire the engine up, it revs right up, as if you had your foot flat to the floor on the throttle. I reflashed the ECU with my original map, but unfortunately the problem is still there. It also throws an error code for the Quantity Adjuster lower limit reached.

I opened up the fuel pump, and found a jelly-like substance (that's British jelly) all over the QA and temp sensor. So I cleaned that off, removed the assembly by unbolting and snipping the wiring terminals, and cleaned it fully out. Putting it back, I set the QA using Measuring Blocks 001 so that it was in spec at both extremes of its movement (0.64V and 4.60V from memory), being happy that I had set that right, I flicked power on, but saw that the QA moves maybe half of its movement before returning, and looking at Measuring Blocks 019 shows values of 0.680V and 0.640V (whereas I believe I should have 0.640V and 4.60V).

Would anybody be able to offer me some advice on solving this please?
I did read a forum post from a Polish chap who had the same ECU as mine, and had put an ACV map with a way different ECU part number (rather than it just being the last suffix being different) and it had bricked his ECU, and he had to solder in a new memory IC and reflash to revive it.

Do you think I've damaged my ECU or at least put some goofy data into it from once of the ACV maps, which is staying there even after reflashing with the original ECU data?

Or is it a problem with my fuel pump or wiring? (I had to cut off the fuel pump plug from the ACV loom and connect it to the Volvo plug for my fuel pump)

As I say, I did have the van running and responsive to throttle input (albeit lumpy), and the revving up issue seemed to have came about by reflashing the ECU (using MPPS).

Any input appreciated!!