C. LH-SFI Control Module, Diagnostic Trouble Codes 19, 51: Overview
C. MODEL 140.057 (MODEL YEAR 1992) LH-SFI CONTROL MODULE, DIAGNOSTIC TROUBLE CODES 19, 51As of June 1992, revised air cleaners and/or LH-SFI control modules have been installed in production to avoid unjustified setting of Diagnostic Trouble Codes 19 or 51.
Effective Serial Number
Model As of Chassis End Number
140.057 A-090745
On vehicles manufactured prior to production phase-in and those still equipped with LH-SFI control modules having the old part no. 012 545 63 32, use the HHT (Hand-Held Tester) to check the long-term adaptation value for both LH-SFI control modules (see Hand-Held Tester Manual, Control Module Programming (Long-term Adaptation), page 23 [Edition 9/92]). No action is necessary on vehicles equipped with LH-SFI control modules having the part no. 014 545 19 32.
If value is 0.88 (lower part load) or higher on both LH-SFI control modules, no action is necessary.
If value is below 0.88 (lower part load) on one or both, replace only the LH-SF] control module(s) with the low value. Replace with part no. 014 545 19 32.
NOTE:
There can be various reasons for the long-term adaptation value being set below 0.88. Before exchanging any parts, ensure that all hose connections that feed into the intake system are installed correctly and have no leaks. It is also very important that all parts of the intake system starting at the air intake duct are installed correctly and that the fuel injection system operates to specification. All of these items have an influence on the air/fuel mixture (because they affect the air flow) and have a great influence on the setting of the long-term adaptation.