Problem, vehicle won't pass state emissions. Used scan tool to read faults from ECM. No output or code data found. This is for a 1991 Crown Vic, 351 intercepter package that includes a feedback carb (crap). Is this a common problem (no output) with the interceptor package? Could the ECM be dead, is it fused? Can anyone help?
ps the specs are HC: 0.87 CO: 16.5 there are no NOX given. CO2: 524.8
Thanks
Are you doing the right test?
Your car does not have the EEC-IV that all other 1991 cars had (1991 5.0 EFI police package had EEC-IV), it has the MCU system. Your scan tool has the capability to read these codes, but the codes are completely different, even though the connector is the same. The 1983 to 1991 5.8 had MCU, while the rest had EEC-IV.
The carb really is not "crap", it is more or less "misunderstood". It can be a reliable and economical set-up when in the hands of competency. Be sure your testing station knows the standards to which this unique (for the model year) engine is to be held to. It is not the same as the FI engine.
Good luck!
Rob
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What is a "feedback carb"? Is it what replaced the variable venturi?
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