1993 Other Infiniti Models My car runs rough between 2300 to

Tiny
H_HARDING
  • MEMBER
  • 1993 INFINITI
  • 6 CYL
  • 2WD
  • AUTOMATIC
  • 194,000 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?
Tuesday, July 15th, 2008 AT 4:07 PM

6 Replies

Tiny
KHLOW2008
  • MECHANIC
  • 41,814 POSTS
Hi h_harding,

Is the check engine light showing?

I would suspect the EGR or throttle position sensor is giving the problem.
Was this
answer
helpful?
Yes
No
Wednesday, July 16th, 2008 AT 11:08 AM
Tiny
H_HARDING
  • MEMBER
  • 4 POSTS
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?
Was this
answer
helpful?
Yes
No
Wednesday, July 16th, 2008 AT 6:02 PM
Tiny
KHLOW2008
  • MECHANIC
  • 41,814 POSTS
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.
Was this
answer
helpful?
Yes
No
Thursday, July 17th, 2008 AT 9:04 AM
Tiny
H_HARDING
  • MEMBER
  • 4 POSTS
Thank you to all that responded.

God Bless.
Was this
answer
helpful?
Yes
No
Thursday, July 17th, 2008 AT 7:23 PM
Tiny
H_HARDING
  • MEMBER
  • 4 POSTS
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.
Was this
answer
helpful?
Yes
No
Friday, July 18th, 2008 AT 8:12 PM
Tiny
KHLOW2008
  • MECHANIC
  • 41,814 POSTS
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.
Was this
answer
helpful?
Yes
No
Saturday, July 19th, 2008 AT 11:14 AM

Please login or register to post a reply.

Sponsored links