They shouldn't if they are tuned correctly.

-Darwin

 

Stop running the engine, fix the dampner and the BOV. Fuel leak is bad, be it a drop or 10. While attending to the fuel problem, check your fuel lines, pay close attention to the short hose to the dampner..
Fix all mechanical engine problems first, make sure you are using the correct FPR for your chip, then check your AFR and MPG.

 

Do fuel leaks cause the pressure to change?

Autothority chips are tuned to the 2.5 bar FPR, right?

 

Change out the fuel filter, I too have been suffering through bad gas milage and I can almost trace it back to a single event in which I ran the car for a long period of time with the low fuel level light on,( 24/ 26 mpg before and 17/19 after that refill). This past Saturday I changed ou tthe fuel filter and since saturday afternoon I have driven 208 miles and am still above the 1/2 tank level. This also means I will have to remove the gas tank sometime in the near future to have it cleaned and recoated but until then I will not be running the fuel level so low as to suck up bits if rust and. particle. Good luck.

 

There is supposedly no tuning required, they are just put on and drive, besides, how do you tune a MAF, there is no way...

 

A fuel leak WILL cause an engine fire eventually. You are taking a great risk by running the car. Follow the suggestions here and do not run the engine until the leak is fixed. Do a search for 944 engine fires and you will be suprised how many this has happened to and how unexpected it can happen.

A leak can also cause a pressure change and bad fuel economy but that should be a secondary concern to your fuel leak.

 

The LR/max chips are ready to run with an afm car, not so on a maf car. Russell told me that they will still need some fine tuning from a piggyback on a maf car due to the differences in the calibrations of the maf.

Rock, it is my understanding that the autothority chips are supposed to be used with the 2.5 fpr, no more.

 

Been there... Done that