PROM - False Code 34 Set During Idle or Deceleration

BulletinNo. T 84-49
File In Group 6C
Number 75
Date Mar. '84
SUBJECT: FALSE CODE 34 SET DURING SUSTAINED IDLE OR LOW SPEED DECELERATION

MODELS AFFECTED: 1982 CIMARRONS - MANUAL TRANSMISSION


Some 1982 Cimarrons equipped with a manual transmission may set a false intermittent code 34 if engine vacuum exceeds the calibrated threshold (10 in.) needed to set a code 34 during a sustained idle or low speed deceleration.

To diagnose this false (intermittent) code 34, perform the "Diagnostic Circuit Check" on page 6E-16 of the 1982 Service Information Manual and physically check the vacuum sensor wiring for proper connections, pinches or cuts.

A service PROM is available through GMWDD to correct this false code 34 in cases where the check engine light appears intermittently during a sustained idle or deceleration. Service PROM part numbers are as follows:

Begin End Service Service Service
B.P. B.P. PROM I.D. PROM P/N ECM P/N

400001 416172 1376AML 1226721 1225330
416173 423220 1464ADN 1225753 1225500
423221 423711 1336AWB 1225751 1225500
430001 432258 1336AWB 1225751 1225500