Bucking and crappy MPG.
08-01-2010, 07:33 PM
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Bucking and crappy MPG. Hello all. I'm looking to sell my car soon because I need a pickup and plan to get a Lightning. No flaming!!!
Anyway, I have a few issues I'd like to fix before selling it as I don't want to lose too much money. Be kinda hard to sell the car as is right now. I just recently installed a T56 with a Textralia OZ700 clutch. Its great. I really do love it. Problem is, this thing bucks like a bronco! Especially at a light throttle cruising. Dropping it down a gear helps a little but not a lot. Plus I don't want to cruise around at 3000 rpm. I have a .224 .224 .581 lift on 112 LSA cam. I had it tuned by a local guy using HPtuners software. He says there is no way to eliminate the bucking. I call 
. Is it possible to tune it out? Its a 98. Also, the idle really sucks. When cold it acts fine. But after warm up, when you cut it off and let it sit for a minute then crank it back up, like going in a store, it drops idle as soon as you release the key and usually cuts off. I usually have to pump the gas to keep it going. I just cleaned IAC and throttle body out which seemed to help but it still surges now. And last but not least, I'm only getting about 16 mpg. Not that I expect a lot out of this but that's ridiculous. I had an 84 Corvette with the crapfire engine that would barely run still get 20 average and 28 on the highway. WTF!!! Thanks for any help.
Anyway, I have a few issues I'd like to fix before selling it as I don't want to lose too much money. Be kinda hard to sell the car as is right now. I just recently installed a T56 with a Textralia OZ700 clutch. Its great. I really do love it. Problem is, this thing bucks like a bronco! Especially at a light throttle cruising. Dropping it down a gear helps a little but not a lot. Plus I don't want to cruise around at 3000 rpm. I have a .224 .224 .581 lift on 112 LSA cam. I had it tuned by a local guy using HPtuners software. He says there is no way to eliminate the bucking. I call . Is it possible to tune it out? Its a 98. Also, the idle really sucks. When cold it acts fine. But after warm up, when you cut it off and let it sit for a minute then crank it back up, like going in a store, it drops idle as soon as you release the key and usually cuts off. I usually have to pump the gas to keep it going. I just cleaned IAC and throttle body out which seemed to help but it still surges now. And last but not least, I'm only getting about 16 mpg. Not that I expect a lot out of this but that's ridiculous. I had an 84 Corvette with the crapfire engine that would barely run still get 20 average and 28 on the highway. WTF!!! Thanks for any help. 
08-01-2010, 07:53 PM
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That can be tuned out... no doubt. As for the MPG, if it runs good cold (open loop), then runs bad when it warms up, you may have exhaust leaks causing the O2 sensors to add unneeded fuel when in closed loop. That may be contributing to the idle issues too... what you need to do is get someone who knows what they are doing to log the car and see what the fuel trims are looking like. Figure out what is going on from there...
08-03-2010, 12:00 AM
#5
do yo have the stock mass air flow? injectors? sounds like your enrichment rate is way off? if you want to email me your tune with a list of the mods you have done i can check it out for you.
check your pm for my info and a trick to help with that idle for now.
check your pm for my info and a trick to help with that idle for now.
