Engine - Surge/Hesitation/Rough Idle

91cadillac01

Bulletin No. T-91-36
File in Group 6E
Number 84
Corp. Ref. No. 036514R
Date JAN. 1991


SUBJECT: CODE 22 - IDLE SURGE, LOW SPEED HESITATION, OR ROUGH IDLE


MODELS AFFECTED: 1991 BROUGHAMS


Some 1991 Broughams with the 5.0L (VIN E) or 5.7L (VIN 7) engines may experience a "Service Engine Soon" light or low speed driveability conditions. This may include a stored code 22 (Throttle Position Sensor), idle surge, low speed hesitation, or rough idle.


This condition may be caused by plastic mold flash on the internal contact pads causing incorrect TPS output.


Follow the normal diagnostics found in Sections 6E2-A, 6E2-B, and 6E2-C2 of the Service Information Manual. If replacement of the TPS is necessary, use kit P/N 17112404. Do not use any TPS that is Julian Date coded prior to C1350. The Julian Date of 135 represents May 15 (135th day of the year), and 0 represents the year 1990 (9 = 1989).

Figure 1 - Throttle Position Sensor:

The Julian date is located on the TPS face just below the production part number. It can be identified without removing the TPS from the throttle body.


Parts are currently available from GMSPO.