ECU problem??? or something else?

The 1UZFE EGR Delete Kit is available for sale here.
Well after much discussion I had the carby guy check his meter and turns out it had a valve in the piping which upset the figures. (He hasn't stopped apologising.)

Anyway new and more accurate figures are

Ignition On - 34.8psi
Idling or reving to 2500rpm - 33.4psi
WOT - 43.5psi

So, with these figures it looks like the pump is failing and the lack of pressure is causing the out fuel/air to lean out. Does this seem logical?
 
No I don't think so.

The WOT figure is exactly what the book specifies.

At WOT the engine is consuming the most fuel it ever will (short of WOT in freezing weather with a cold engine) and the pump is keeping up the pressure.

If it wasn't flowing enough fuel the pressure would drop as the injectors would be using the fuel faster than the pump can supply it.

I'd rule out the pump.

In an earlier post you mentioned the reg "reducing pressure", the reg doesn't actually reduce the pressure itself. The pressure is regulated by how much fuel the reg allows into the return line. If the pressure is too high it opens up the valve a little more until the pressure drops, if low it closes up a little.
 
Well after the most annoying, solution sorting week, my driveability problems has finally been solved, and because I hate reading forums where there's no outcome to problems posted, here's mine.

After niggling problems , leading to disasterous driving conditions, the one thing that has come out of this is WRITE DOWN WHEN YOU DO MAJOR THINGS that can have an effect on the cars/motor operation.

To cut a long story short, last year I swapped in a new 02 sensor, then some months later did the other one, but I had forgotten that the car had not been driven further than around the block during that time. By the time I got around to driving it properly some 4 months had past so when this problem arose I had forgotten what had changed.

So, the new 'universal sensors' have been sending incorrect info to the ECU which leaned out the fuel/air so the further the car goes, the worse the problem gets. The ECU has a base A/F ratio it can run on if the sensor fails, (hence the ok driving after the ECU is disconnected) but if it gets incorrect info it just follows what its told. Eventually, for me this meant a motor trying to run on a very, very lean air/fuel mixture.

New 02 sensors will be installed in coming weeks, but in the meantime, I have disconnected the 'universal' items to run, pain free, on the ECU's base setting, which is probably how it was before I tried to 'fix' the problem.

Thanks to all that tried to help.
 


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