after lookin thru the gas milage forum i am wondering why i am getting such horrible gas milage. let me tell you about the car first
97 grand am GT
3.1 came in it stock i bought it with a blown motor and put in the all mighty 3.4
now i kept the stock 3.1 injectors and computer and put in the 3.4 lower/upper intake with no EGR. it has a code in the computer for no EGR right now. and that is the only code after 4-5 months of driving it. the car starts right up i drive it 3 miles to work and 3 miles home. i get about 150-160 miles a tank and that lasts me about 3 weeks as of now. im kinda disapointed in the 11 miles/gal or so. any swap guys or GM guys that have any ideas why i get shitty gas milage.
Pontiac/GM motors don’t really go by year…3100sfi and the 3400sfi are the engines used in some of the newer vehicles…grand am gt’s after like 2000(i may be wrong) were more known to have the 3.4
Def. sounds like EGR is causing the problem, why didn’t you hook up teh system? If you need an adapter plate for the 3400 UIM, I can more than likely find you one, then you just plug it up to the original. I had shitty gas mileage on my Beretta (3100), but I changed out the plugs/wires/fuel filter, plus I had to replace some stuff relative to the evap system, which is probably unrelated, but still. I would def. try to correct the EGR though if possible.
After I replaced all those though, I noticed I can get about 380 miles to a full tank (15.7 gal)
