First, a genuine new MAF and it is fixed. I didn't fit it and the car has gone so no Post Mortem info is available.
Or has the duration been opened up because it thinks it's lean??? I say thinks because I would consider, generally, 5 ms long enough to inject plenty of fuel.
That does not sit right with me either.
For sure the first Air Mass was under reporting the air entering the system hence a good reason for it to throw less fuel then required accounting for the Lean Condition and Rough Idle. To be precise the injector durations were flickering around 4.5 - 4.7 ms, not often hitting 5ms, O2S1 was constantly lean and I could force it rich. At those durations I would have expected it to run rich. Cant quite get my head around that right now.
Did you happen to see injection duration after you dialled in the Pot's?
Yes the dropped back to 2.3ms, that I was happy with
Why was this rebuilt? Badly cooked? High Km's?
In an attempt to cure the this fault, the replaced rings and re seated valves. - Who knows for sure ? Most of what I hear turns out to be Botox from some of the establishments that I get called to.
In the same place, under the care of the same technician a 1991 Escort RS Turbo Non Start. He has spent 2 days stripping the fuel metering unit and anything else fuel related that he can get his hands on.
The job was passed to me with Spark and fuel at injectors confirmed !!!
I probed the Fuel pump from the relay under the dash and could hear it running, pulled the pipe between tank and pump to reveal no fuel in the tank. Put fuel in it and the pump has died, it now trips out my probe (8 amp circuit breaker) Fit a new pump and it is now pissing out fuel from the return pipe above the tank - Yes they have just fitted a new tank to it.
Its all wrong and they have been in business for 30 odd years.