what are some of the causes of bad gas mileage....

[ThePhoenix]

I mean, I was getting around 17-18...sometimes even 20, which is perfectly fine by me..

then all of a sudden it dropped to 15. I has a collapsing vaccuum hose, which I fixed but it still wont got back up

I did plugs and wires less than 7k ago. I seafoamed it recently...1/2 can so i wouldnt have to change the plugs again

is there an order I should check sensors and such?

I might mention that somedays I do a lot of stop and go driving (pizza deleivery) ...would the computer still log my style of driving and for that and then when I am on the highways, burn gas and such at the same rate? in essence, not reset

any help would be appriciated

chaz

 

[410Fortune]

tire pressure

dragging brakes

 

[ThePhoenix]

hmm...forgot about tire pressure. I will check that on way home

 

[technoboy235]

I would say cold weather but thats probably not a problem in Florida...

 

[eXcali]

I might mention that somedays I do a lot of stop and go driving (pizza deleivery) ...would the computer still log my style of driving and for that and then when I am on the highways, burn gas and such at the same rate? in essence, not reset

I don't understand what you mean by the computer logging your driving style. The thing that decreases your mileage in the city is stop and go driving. Cars get better mileage on the highway because you are maintaining a speed and in most cases you are in the vehicles top gear. There are wind resistance factors and such to keep you from getting outrageous numbers, but even in my wife's car she gets 32mpg driving to my parents house (150 highway miles 10 city) But in the city she averages 18mpg.

I would imagine since you are delivering pizza you are rushing to your delivery and doing a lot of jackrabbiting from stops. When I do this there is a 5-9 mpg swing in my mileage.

 

[J.A.F.E.]

I just had an interesting lesson with gas mileage in my 5.0. I bought mine 4 years old and it got crappy mileage - rarely better than 220-230 a tank sometimes not even. I recently started throwing codes related to the temp sensor and after replacing it and flushing the cooling system fuel mileage has improved quite a bit.

Don't which it was but the improvement is quite welcome.

 

[ThePhoenix]

i thought the computer adjusted ot your driving style...or is that my wife's jetta...like if you drive agressively, it will shift different etc...

i tried making sure my tire pressure was good...it was...I tried going REAL slow off starts at lights...even whne I just drive straight highway, no pizza delivery...still 15
puzzled