Restricted fuel system affect mpguino readings?

[wagonman76]

Ive charted my last few mpguino tank readings compared to actual fuel usage. It started out very close, then read 4% high on fuel use twice, then last time was 8.5% high on fuel use.

Ive also had a couple times in the last few tanks where the fuel seems restricted, and it acts like it is almost out of gas for a bit. I know, I need to change the fuel filter since the pump seems to act just fine.

But anyway, I was wondering if this could actually cause the readings to be skewed? Like say the injectors are firing (and even firing even longer because of more throttle while attempting to go faster) but the actual fuel is not getting through. So fuel usage reads high. Until the computer compensates, if it even can accurately.

And if this is the case, this could even be a bonus of the mpguino, if the fuel usage starts to read high fuel usage (or low mpg), it could be a sign of reduced fuel pressure and an early warning to fuel system problems.

[dcb]

Absolutely. If the fuel system pressure is dropping due to an overly clogged filter or pump problems then the injectors have to stay open longer (and would look like more fuel going into the engine).

Same is true if the injectors are getting clogged, they have to spray longer to keep the o2 sensor happy.