Running without a MAF
 

After regularly getting 50 to 54mpg, my CDT started to miss quite a bit....after engaging the help of MarinaBrian and his magic wand, we watched as my duff MAF was missing and then over fuelling....Brian disconnected the MAF and everything was hunky dory, but I wondered what MPG I would now get....

My OBD always worked out about 10% higher than my brim to brim tests( I check it brim to brim every week...so i know its correct). My OBD was now displaying(without the MAF) around 42-44mpg.....which if 10% had to come off that is disastrous compared to my actual(brim to brim) 50-54mpg with a good MAF....

However.....I filled up again today(for the first time) after disconnecting my faulty MAF.....

I had done 403 miles and filled up(back to the brim) with 39.03 litres of BP...The OBD was displaying 44.1 mpg, but I expected les than this(as explained above)

The 403 miles on 39.03 litres works out at 10.325 miles per litre or 46.9mpg.....which I am over the moon with....and needn't rush out and buy a new MAF...


I'll continue to monitor this at every fill up.. but there doesnt seem any real urgency now in buying a new MAF....although I will keep an eye on those Bosch MAFs on ebay, just incase this useless government manages to strengthen the £ and the price drops.....

Stop frabbling Bob, get a new MAF now :)
Then all will be really well with your car ;)
Brian :D

It is recommended that you do not drop the fuel level below a quarter tank, as it could accelerate the in tank fuel pump failure.

I never let mine (or very rarely) go below a half tank.

I will Brian.....but its not as urgent as I thought it was before my brim to brim.

Merry Christmas mate, and have a good New Year...and thanks again for sorting my problem..I love them "lazy windows"......lol

I never let mine go below the quarter mark, (which on mine is about 180 left in tank).

I lost an in-tank pump once, and although there was no evidence that, that was the cause, I still refuel before then...

When I refuelled today at 403 miles...it still said there was 226 miles left in the tank...but according to my brim to brim result, I think there was more than that....

Andrew have you had a listen to see if your ITP is still working?

Agree if you never let your tank run below a quarter full then you won't notice a failed ITP, but fail it will and it has no bearing on tank level, as all the ones I've seen the commutator has worn out.

Mike

I find that if the maf is left disconnected for too long the ecu will eventually default to a pre determined map which you will see as a drop in power. Like Brian says, sort when you can then its done :)

Actually not checked recently, bit difficult on your tod :icon_smile:

Anopther thing to try and remember to do:shocked:

Absolutely. When I bought my 75, it was dead flat to drive, and the ECU had been disconnected for a year or more. I fitted a new sensor to it, and the difference was very noticeable.

I thought with low level there was a chance on say turning a corner, that all the fuel could go over to the side of the tank where the pump isn't......causing it to run dry for a time......Does this running dry not have an ill effect on it...

Thanks for this, theres no doubt, I have lost power, but with still getting 46mpg, the loss is quite acceptable, although I will get a Bosch MAF after the year....