Rough Idle, Hesitation or Surge, DTC's E34/E45 Set
90cadillac04Bulletin No. T-90-59
File in Group 6E
Number 78
Corp. Ref. No. 016509
Date March, 1990
SUBJECT: ROUGH IDLE, HESITATION OR SURGE ON ACCELERATION; OR INTERMITTENT CODE E34, AND/OR CODE E45
MODELS AFFECTED: 1990 DE VILLES, FLEETWOODS, ELDORADOS, AND SEVILLES
Some 1990 DeVilles, Fleetwoods, Eldorados, and Sevilles may experience a driveability condition described as a rough idle, hesitation or surge on acceleration; or an intermittent code E34 and/or code E45. This condition may be due to a leaking/kinked vacuum hose from the MAP sensor to the throttle body.
To diagnose this condition:
1. Visually inspect the vacuum hose to the MAP sensor for leaks or restrictions. If necessary, replace the vacuum hose with P/N 9439274 (bulk quantity) or equivalent (i.e., 7/32" diameter and 1-3/4" long).
2. If a visual inspection of the vacuum hose does not find the cause of the problem, refer to the appropriate Service Information Manual (Section 6E, Subsection B, under Symptom Diagnosis); or if code E34 or E45 is present, refer to Section 8D1 for diagnosis.