Mechanics

MODELS MY CAR RUNS ROUGH BETWEEN 2300 TO

1993 Infiniti Other

Engine Mechanical problem
1993 Other Infiniti Models 6 cyl Two Wheel Drive Automatic 194000 miles

I have an old Infiniti J30 with about 194000 miles on it. As old as it is, I love the car but the old girl is sick right now. With the car in drive and moving If I accelerate up to 2300 rpm, I loose all power with little or no throttle response, and the car starts jerking. When I stop and place the car in neutral I rev up the engine and at around 2300 the engine begins to run rough as I increase rpm beyond 2500 the engine once again revs up smoothly with good throttle response.
The transmission shifts normally with no issues that I can tell. At this point I think it may be the timing belt but I'm really not sure. Can you offer any suggestions for me?
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H_harding
July 15, 2008.




Hi h_harding,

Is the check engine light showing?

I would suspect the EGR or throttle position sensor is giving the problem.
AD

KHLow2008
Jul 16, 2008.
Hi and thank you. No the check engine light is not on but I never thought about the throttle position sensor, thank you.

Can you tell me what the throttle position sensor does?

Tiny
H_harding
Jul 16, 2008.
Hi h_harding,

The function of the TPS is to inform the ECM of the throttle opening, ie. How much you have depress the accelerator.

This coupled with the engine rpm, vehicle speed, air flow, engine temp etc would tell the ECM what needs to be done.

KHLow2008
Jul 17, 2008.
Thank you to all that responded.

God Bless.

Tiny
H_harding
Jul 17, 2008.
One last question. Where is the throttle position sensor physically located? I know where the ECM is but I'm not sure where the TPS is located.

Thank you.

Tiny
H_harding
Jul 18, 2008.
Hi h_harding,

You are always welcomed to come back with more questions.

The TPs is located on the throttle body and is installed opposite the throttle cable. If its is a fly by wire, then it is located next to the accelerator pedal.

KHLow2008
Jul 19, 2008.

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