On the EU2's the MAF controls EGR only, so if you've have EGR removed, and the solenoids unplugged the EGR will turn off after around 20-30 seconds and stay off until the next start. EGR is used to reduce amount of oxygen in the cylinder under certain conditions, and this tends to reduce fuel consumption. So deleting EGR will definitely increase consumption, and emissions.
For EU2 if the EGR is still connected you really want a properly functioning MAF.
On EU3's the MAF is used as the primary method of calculating airmass in the cylinder. This value is mainly used to set the maximum inject limit for a given amount of available air. If you unplug the MAF the ECU will fall back to using the MAP/IAT to calculate the same airmass parameter.
The downside of unplugging MAF is considerable. The EU3 uses different smoke limiters for High and Low range, and the high range limter consists of two maps that are used to improve drivability - basically the ECU ramps between the two maps over a short period (1-2 seconds) to smooth transitions. If you disconnect the MAF the EU3 "dumbs" down a EU2 style smoke limiter - a single map for both high and low range.
In addition there is a 20-30second timeout of the MAF, so when you first start the engine there is a short period where the throttle doesn't respond. Once the MAF times out, throttle starts responding.
There is information on how to modify the variant map to remove the MAF timeout on my site. But I'd stress that the main reason that information exists is due to requests from off-road racers who found the timeout a major issue. It's not intended as a clever hack for cheapskates with EU3 motors - you are far better off with a properly functioning MAF .
And no the TPS voltage into the MAF is not smart. The TPS has a linear curve, while the MAF doesn't.
You will never get an accurate reading by this means. It's actually worse than running a bad MAF.


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