Diagnostic With Obd1: Print That Page
LMP
02-27-2005, 12:32 PM
If you have OBD1 equipped (till '94 and some '95) Transport, download that page and print it.
www.avigex.ca/xport/readingdiagnostics.jpg
More that reading the codes, one very useful tool is the FIELD SERVICE MODE,seldom mentioned. (see paragraph). In that mode (running the car with the "paperclip" connected to A and B) one can see if the car operates in the "feedback" (closed loop) mode that ensures proper fuel metering. When not in closed loop, car runs in "open loop" with default values that are just there to ensure the engine runs, that's ALL.
Since some faults can impair closed loop operation, this may have detrimental effect on fuel consuption, among other things.
www.avigex.ca/xport/readingdiagnostics.jpg
More that reading the codes, one very useful tool is the FIELD SERVICE MODE,seldom mentioned. (see paragraph). In that mode (running the car with the "paperclip" connected to A and B) one can see if the car operates in the "feedback" (closed loop) mode that ensures proper fuel metering. When not in closed loop, car runs in "open loop" with default values that are just there to ensure the engine runs, that's ALL.
Since some faults can impair closed loop operation, this may have detrimental effect on fuel consuption, among other things.
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