Problem here
 

recently when i drive my car, i notice momentary interruptions in performance. it only happens in 3rd, 4th, and 5th gear as far as i can tell, and only at or above 3500 rpm. when i get in that range my car will start to jerk a bit, like its lost all power then gets it back the next instant. im going to do a diagnostic test tomorrow and i will post the results, but until then if someone has any ideas id really appreciate hearing them. im also going to rev the engine to 3500rpm in neutral to see if its most likely an engine or tranny problem. its a 86.5 n/a manual. is there a way to do a diagnostic test on the tranny? thanks for your help

did you find code 52? if so the knock sensor or the wiring will do that..

the codes i pulled are:
-41-throttle position sensor signal
-42-vehicle speed sensor signal
-43-starter signal
-51-switch condition signal

ive heard something about having you air conditioning on and getting 51, so i made sure mine was off.

i have an 86.5 na 5spd i find mine only jerks really bad when the car is cold and i go to shift it act as if the car stalls out, and then i get all my power back dont take the car to autozone to get the free dignostic cause they cant do cars under like 96 or somthing stupied like that

Code 41 and 42 are self explanatory.


Code 43 means there is no STA signal to ECU when the engine is running over 800 rpm. Which could mean there is a problem with the main relay circuit or ignition switch circuit. If your starter works, I would check the wiring between the STA (terminal 50) and the ECU. The STA terminal is the one wire plastic end connector that clips to the starter.

Code 51 could be a number of things. If your A/C was off as you said and you have a 5spd car, then it could be the throttle position sensor or circuit, or it could be the ECU.

I would start with the throttle position sensor and vehicle speed sensor. Im pretty sure the W58 trans speed sensor is on the top of the trans toward the rear and the R154 trans speed sensor is on the drivers side of the trans toward the rear.

Hope this helps.