1996 Cadillac SLS Engine surge with DTC P0503

Tiny
MREARLY2
  • MEMBER
  • 1996 CADILLAC SLS
  • V8
  • FWD
  • AUTOMATIC
  • 127,000 MILES
The oil-leaking engine runs fine, but surges when driven (I don't recall at what speed that begins). I checked for trouble codes and a "P0503 Speed Sensor A" shows up. Is "Speed Sensor A" the one on the passenger side? I have replaced the speed sensor at the passenger-side trans output. It is possible the wiring to that is faulty, but I found it easier to replace the sensor, than mess with the wiring; however, that didn't solve the problem. Can I check the plug for the sensor, to tell whether it is receiving proper input?
Monday, October 19th, 2009 AT 11:16 AM

2 Replies

Tiny
MATHIASO
  • MECHANIC
  • 1,209 POSTS
Yes. Here is what you need to do:
raise and safely support the vehicle
disconnect the VSS wire connector
connect an ohmmeter between the terminals
most sensors usually between 190-250
ohms
place the vehicle in drive and allow the wheels to rotate.
The ohmmeter should fluctuate, if it does not or if it not within that specification, replace the sensor.
Was this
answer
helpful?
Yes
No
Monday, October 19th, 2009 AT 6:29 PM
Tiny
FACTORYJACK
  • MECHANIC
  • 4,159 POSTS
You could check the terminal tension of the connector, with a terminal of the corresponding type(metri-pak 150 male). The speed sensor is a signal generator, the only way to check the circuits would be to measure them individually, from the sensor connector to the ECM connector. Is the code shown to be history, or current, and if cleared does it reset? Also, does the speedometer seem to function properly?
Was this
answer
helpful?
Yes
No
Tuesday, October 20th, 2009 AT 12:29 AM

Please login or register to post a reply.

Related Engine Surge Content

Surging
GUIDE
Surging
An engine or motor surge is caused by an imbalance in the computer system which cannot be corrected within the parameters of the vehicle's operating program, in other...
VIEW MORE