Question
A family member of mine has a 1981 Chevy Citation w/ about 56,000 miles and a V6 ...About 1/2 year ago ... the car was hard to start ... and over time it got to the point where it would NOT start !! It cranked fine ... but no starting ... and when it ran ... it performed great, with no hesitation or any other symptoms ... only upon starting ....So ... he took it to a local mechanic ... and they worked on it 5 separate occassions over 3 months!! Each time ... they replaced another part ... (not enough diagnostic investigation if you ask me) ... They replaced fuel pump, carburetor, plugs, wires, ignition coil, distributor cap, distributor rotor, ignition module, thermostat, temperature switch, air filter, rebuilt computer and a NEW PROM for the computer...So now ... it comes down for my analysis ... and I purchased a genuine GM service manual for that car ... and I have pinpointed the problem to the ignition system NOT fuel related ... And I found this out by disconnecting the 4-way connector from the ECM to the distributor ...When I disconnected it ... it would start on the first crank ... but ran rough ... because the ignition module was controlling the spark curve ... and as soon as I connected the ECM ... it stalled ...I have tried to follow most of the flow charts in the manual ... but I cannot uniquely identify what part of the ignition system would be causing the failure ... As noted above ... the module was replaced, as well as the computer ... And the only other possibility is a short ...IF you advice at all about how to further isolate the problem ... to the computer ... ignition components ... or wiring ... They are all 3 major areas of diagnosis ... and being able to isolate to (1) system would be of great help !! Thanx -- GZ --
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