tps .74 at closed throttle lg4
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Car: 99 grand am, 87 buick turbo T,
Engine: 3.4; 87sfi turbo
Transmission: 4spd OD; 4spd OD BRF valve body
tps .74 at closed throttle lg4
Any reason why it would be this high? I thought stock setting was .40-.48? I moved the throttle up and down and it goes up nice and smooth. I've snapped the throttle closed a few times with the same result. Nothing changes with the car running either. Could this be the cause of the tip-in stumble and slight bog I get when at operating temperature?
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Car: 1987 SC/1985 TA
Engine: 350/vortec/fitech
Transmission: T56
Axle/Gears: 3.27 9-bolt
Re: tps .74 at closed throttle lg4
Not necessarily too high, but it can be adjusted. Probably not the cause of any driveability issues, may cause delay of the release of the idle bump solenoid on decel.
Make sure the throttle is resting on the curb idle set screw and the idle is near 600 (all after ensuring ignition is up to snuff and base advance is set). Adjust the TPS by removing the cap over the set screw (on carb near booster fulcrum). You can lightly tap a roll pin over the screw to adjust instead of buying the 'special' tool.
Make sure the throttle is resting on the curb idle set screw and the idle is near 600 (all after ensuring ignition is up to snuff and base advance is set). Adjust the TPS by removing the cap over the set screw (on carb near booster fulcrum). You can lightly tap a roll pin over the screw to adjust instead of buying the 'special' tool.
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Car: 99 grand am, 87 buick turbo T,
Engine: 3.4; 87sfi turbo
Transmission: 4spd OD; 4spd OD BRF valve body
Re: tps .74 at closed throttle lg4
I've already done the major tune up. It does run a lot better. I haven't checked the timing yet though, haven't had anyone around to hold the brake for me. The hesitation is very slight right off closed throttle. It only does it if I barely push on the gas. THe car idles right at 650. Should I check timing first? What should I set timing and tps at? The throttle does rest on the stop screw
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Car: 1987 SC/1985 TA
Engine: 350/vortec/fitech
Transmission: T56
Axle/Gears: 3.27 9-bolt
Re: tps .74 at closed throttle lg4
Base timing can be per the sticker under the hood or 2-4 advanced with the four-wire esc connector disconnected from the distributor. Adjust TPS for 0.40 at idle.
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Car: 99 grand am, 87 buick turbo T,
Engine: 3.4; 87sfi turbo
Transmission: 4spd OD; 4spd OD BRF valve body
Re: tps .74 at closed throttle lg4
I'll check the timing tomorrow. If it isn't that I'll try to get around to adjusting the tps and report back. I also bought a new denso 02 I'm gonna put in before I adjust the tps
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Car: 99 grand am, 87 buick turbo T,
Engine: 3.4; 87sfi turbo
Transmission: 4spd OD; 4spd OD BRF valve body
Re: tps .74 at closed throttle lg4
timing was dead set at 0*. I bumped it up to 2* and pulled the seal on the tps and adjusted it to .46. Still stumbled right at 800 rpm. Doesn't matter if it has a load or not. I'm lost. What else could be causing this? I checked the efe flap to make sure it wasn't stuck when the engine was cold and I saw it move so I know that works, haven't tried it when it's hot though. Does anyone have any ideas? I've burned up 20 bucks in gas trying to figure this thing out. This is driving me nuts!
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Car: 99 grand am, 87 buick turbo T,
Engine: 3.4; 87sfi turbo
Transmission: 4spd OD; 4spd OD BRF valve body
Re: tps .74 at closed throttle lg4
Didn't find anything wrong with the carb as far as the items I checked. I decided to check the resistance of the coolant temp sensor with the engine at operating temperature. According tot he scale in the haynes manual, the sensor is telling the computer the engine is still under 100*. Pretty sure I found the running problem. SUrprisingly the thermac valve on the air cleaner I got from the junkyard actually works and the EFE is also operational. I will follow up tomorrow after the sensor install.
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