Exhaust System - Rotten Egg Odor
87cad7Bulletin No. T 87-124B
File in Group 6E
Number 46
Corp. Ref. No. 716506R
Date Oct. '87
SUBJECT: ROTTEN EGG ODOR FROM EXHAUST
MODELS AFFECTED: 1986-1987 DE VILLE, FLEETWOOD, BROUGHAM, ELDORADO, SEVILLE, AND CIMARRON
This bulletin supersedes Bulletin T-87-124A, Group 6E which should be destroyed.
Some 1986-1987 De Villes, Fleetwoods, Broughams, Eldorados, Sevilles, and Cimarrons may exhibit a "rotten egg" odor from the exhaust system. If present, the odor will be most evident during idle conditions.
To repair a "rotten egg" odor condition, it is important to first check those items which may cause a vehicle to run excessively rich. These include (but are not limited to):
- Check for normal engine operating temperature, - Check for excessive fuel pressure, - Check for incorrect idle speed, - Check for incorrect engine timing, - Check for leaking fuel injector.
Refer to the appropriate model Cadillac Service Manual, Section 6E-B, "Excessive Exhaust Emissions (Odors)," for more information.
FIGURE 1:
FIGURE 2:
DE VILLES, FLEETWOODS, ELDORADOS AND SEVILLES
If proper vehicle operation is verified and the odor condition persists, install a new catalytic converter (part numbers listed) using the following procedure (refer to Figures 1 and 2):
1. Raise the vehicle and support the catalytic converter.
2. Disconnect the A.I.R. hose from the converter.
FIGURE 2:
3. Using tool J-35976, BT-8252 or equivalent, cut the intermediate pipe at the converter, as close to the weld as possible (see Figure 2).
4. De Ville/Fleetwood - Cut the exhaust pipe at the converter as close to the weld as possible (see Figure 2).
Eldorado/Seville - Remove the two bolts and springs from the exhaust pipe to converter flange.
5. Remove the catalytic converter (and seal on Eldorado/Seville).
6. Collapse and remove the portion of the catalytic converter inlet/outlet remaining in the intermediate pipe (and exhaust pipe on De Ville/Fleetwood).
7. Install the new catalytic converter. The converter inlet/outlet will fit inside the existing pipes.
8. Eldorado/Seville - Install a new exhaust pipe to converter seal, P/N 1633384. Install the exhaust pipe to converter flange bolts/springs and torque to 20 N-m (15 ft.lbs.).
De Ville/Fleetwood - Install a guillotine-type clamp, P/N 15595048, at the exhaust pipe to converter fitting. Torque to 35 N-m (26 ft.lbs.).
9. Install a guillotine-type clamp, P/N 15595048 (except C-touring use 3634476), at the intermediate pipe to converter fitting. Torque to 35 N-m (26 ft.lbs.).
10. Reconnect the A.I.R. hose, lower vehicle, start engine and check for exhaust leaks.
PARTS LIST
Part Name Model P/N
Catalytic Converter De Ville/Fleetwood 25104174
Catalytic Converter De Ville Touring 25103959
Catalytic Converter Eldorado/Seville 25104175
BROUGHAMS AND CIMARRONS
If proper vehicle operation is verified and the odor condition persists, install a new catalytic converter using the part numbers listed below.
1986-1987 Brougham (Federal Emissions) 25103919
1986-1987 Brougham (California Emissions) 25103918
1986 Cimarron 25104705
1987 Cimarron 25104025
WARRANTY INFORMATION
For warranty purposes, use Labor Operation T5141 at:
- .8 hour for De Villes and Fleetwoods
- .6 hour for Eldorados and Sevilles
- .8 hour for Broughams
- .3 hour for Cimarrons