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hey guys, how to get LTFTs down to negative?

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Old 12-29-2004, 01:19 PM
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Default hey guys, how to get LTFTs down to negative?

My car has been getting crappy mileage, around 10mpg, and i hooked it up to my buddys efi live and did some casual driving, at idle im at -2.3 and -0.8 then at partial throttle, i will be at +5.5 and +8.3 and at full throttle, around 4-5ish. I also get KR around 3800 and sometimes at low rpms. nothing really has changed on the car when all this started to happen, except moving to montreal, canada and my first tank of gas here. Had to have a cat replaced because i threw the bad cat code, but at that point my mileage was around 12mpg, then after the cat was replaced, went down to 11, then 10mpg then sometimes flirting with 9mpg. Any ideas. Car has new plugs/wires, new front o2s, new fuel filter, new oil. me and pretty much everyone else is stumped and montreal, let alone the rest of Canada sucks for anyone who has good knowledge of these cars, except some euthiasiasts. Car is in storage now. So far all i have is clean my maf, even though i didnt oil my filter, so i dont get how it could be that.

Mike
Old 12-29-2004, 10:45 PM
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Well your idle LTFTs are pretty much fine...but your part throttle should be checked in a certain gear under a certain load for a certain time. For example, 3rd gear @ 3000rpm for 5mins or so... You can even lock the speed with cruise control. But sounds like you are actually running lean if your part throttle LTFTs are accurate as far as what you say they are.

Does the engine burn much oil/any oil?
You should get it on a dyno or if you have access to a handheld wideband that would be good too...
Old 12-30-2004, 01:41 AM
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i think it burns a half quart every 1000 miles, maybe a bit more or less depending on driving, however, i had the car for a year before it started getting crap mileage, so something changed dramatically, but the only thing that has is the gas i use, Canadien gas which is 91 and the 94 they sell supposedly has an additive that clogs the injectors to make the fuel system not freeze or some crap in the winter, but they run it year round. My car was used to 93 sunoco, never had any problems. The car is stored but i wanna figure this out before i take her out, gas prices arent cheap here and 10mpg isnt cutting it! But noone else has this problem with their cars running on the gas, are cars that sensitive to gas or is it coincidence it started after the first fillup of Canuck gas and went down hill from there.
Old 12-30-2004, 01:42 AM
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i checked behind the TB, because when i replaced it with the ported one, i checked for oil right after the TB, i couldnt find any in the intake.
Old 12-30-2004, 01:45 AM
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I know positive trims indicate a lean condition, ive been doing tons of reading, but i talked with some pros on this site and others and showed them my logs, and they are at a loss for getting 10mpg throwing no codes and o2 lock in at around .890. .900 at WOT. I think i need to get my idle trims down to like -5 or so, because -0.8 is to high for idle considering, idealy i want 0 when i hit WOT. I think my air pump doesnt work anymore because i never hear it come on but i havent thrown any lights.




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