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P1635 Diagnostic Trouble Code Discussion for May 2004

5-Volt Reference 'A' Circuit Malfunction

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Trouble Ticket Help Requests for DTC P1635
Help Request Posted
1998 Buick LeSabre Custom 3.8L Poor Idle Quality, Hesitation, MIL Lamp on VIN: 1G4HP52K4W
P1635: 5-Volt Reference 'A' Circuit Malfunction. Hi Guys, This car came in with all the listed codes & a pile of receipts from other garages. This Buick has an interrmittent MIL that comes on. The three sensors corresponding to the codes are on the same 5V. reference line, although when I backprobe it a...
May 23, 2004
1995 Chevrolet Camaro 3.8L Poor Idle Quality, Hesitation, Stall VIN: 2G1FP22KOS
P1635: 5V reference A circuit problem. ... most of the time but intermitently when coming to a stop the idle starts to vary from 800 to 2200 rpm when at a stop light your foot better be on that brake pedal realy good because when it decides to surge it tries to take off almost like power braking it...
May 31, 2004