99 accord rpms bounce when given throttle

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Jan 30, 2019 | 04:36 AM

99turboaccord

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99 accord rpms bounce when given throttle

Hi, I just recently did a full rebuild on my 99 accord. I pulled the engine and trans, got the motor to a bare block and rebuilt it. Replaced all the gaskets, bearings, new oil pump, water pump, head bolts, etc. Got the engine all back in the car and it starts but when I give it throttle the rpms bounce. If I rev the car to 2.5k, it will go between 2.5 and 1.5, the more throttle I give it, the higher the window. I did some research and found that the TPS and MAP sensor use the same plug, so it’s likley I have them plugged in backwards. I have not tried this yet, anyone have any ideas? I’m not getting any check engine codes either, except for a 02 sensor which I know will not cause the car to do this.

Jan 30, 2019 | 12:44 PM

MAD_MIKE

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From: 94577/Gaillimh

Re: 99 accord rpms bounce when given throttle

Disconnect the TPS or MAP, not both. Turn ignition to II(ON).
If you disconnected the TPS but now have a MAP code pop up, or vice versa, then you know if you have swapped the connections.
If the sensor is the correct one disconnected, recheck your grounds, gaskets and vacuum hoses are correctly installed.
Then recheck that the sensors themselves are still good.
TPS should have a nice linear voltage sweep when checking from idle to WOT.
MAP sensor, you will need a vacuum pump, should also have a smooth voltage change ~1volt for every 5inHg change.
Verify that you have all the air out of the cooling system via the bleed valve on the thermostat housing.

Jan 30, 2019 | 01:14 PM

2pac1

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Re: 99 accord rpms bounce when given throttle

tps plug is blue.

Mar 1, 2019 | 08:46 AM

quicksandcd7

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Re: 99 accord rpms bounce when given throttle

I agree with what has been said above. My friends golf had the same thing happening (MAF sensor was on backwards) I know the accord has a MAP sensor so I would start there. Best of luck!