Может эта картинка натолкнет товарища дуста на мысль о стрелке.
Все банально просто.
И описание из Митчелла. За перевод звиняйте, сами.
Fuel Gauge Inaccurate (Single Tank)1. Disconnect IPC connector. Connect fused jumper wire between IPC terminal No. 22 (Pink wire) and
voltage. Install another fused jumper wire between IPC terminal No. 31 (Black wire) and ground.
Connect one Red lead of Instrument Panel Tester (J33431-B) to IPC terminal No. 16 (Purple wire).
Connect other Red lead to ground.
2. Set resistance dial to zero ohms. Fuel gauge should indicate "E" or below. Set resistance to 90 ohms.
After a short period, gauge should indicate "F" or above. If fuel gauge does not operate asspecified,
replace IPC. If fuel gauge does operate as specified, go to next step.
3. Remove fused jumper wire between voltage and IPC. Install a fused jumper wire between ground and
IPC. Reconnect IPC connector. Disconnect fuel pump and sender. Connect one Red test lead to fuel
gauge sender terminal "B" (Purple wire). Connect other Red test lead to ground. Set resistance dial to
zero ohms, then to 90 ohms. If fuel gauge does not operate, locate and repair high resistance in Purple
wire between IPC and fuel gauge sender. If fuel gauge does operate, go to next step.
4. Reconnect tester between fuel gauge sender terminals "B" (Purple wire)and "A" (Black/White wire).
Set resistance dial to zero ohms, then to 90 ohms. If fuel gauge operates, replace fuelpump and
sender. If fuel gauge does not operate, locate and repair high resistance in Black/White wire between
fuel gauge sender and ground.
Fuel Gauge Indicates Full Or Greater At All Times (Single Tank)
1. Disconnect IPC connector. Connect fused jumper wire between IPC terminal No. 22 (Pink wire) and
voltage. Install another fused jumper wire between IPC terminal No. 16 (Purple wire) and ground.
Install fused jumper wire between IPC terminal No. 31 (Black wire) and ground. Turn ignition on. If
fuel gauge indicates full, replace IPC. If fuel gauge indicates empty, go to next step.
2. Remove fused jumper wires from IPC and reconnect connector. Disconnect fuel pump and sender
connector. Connect a fused jumper wire between fuel sender connector terminal "B" (Purple wire) and
ground. If fuel gauge indicates full, locate and repair open circuit in Purple wire between IPC and fuel
gauge sender. If fuel gauge indicates empty, go to next step.
3. Replace fuel pump and sender. If fuel gauge indicates full, repair open circuit in Black/White wire
between fuel sender and ground. If fuel gauge indicates empty, replace fuel gauge sender.
Fuel Gauge Indicates Empty When There Is Fuel In Tank (Single Tank)
1. Disconnect fuel pump and sender connector. Turn ignition on. If fuel gauge does not indicate empty,
replace fuel pump and sender. If fuel gauge indicates empty, go to next step.
2. Turn ignition off. Disconnect IPC connector. Connect test light between IPC connectorterminal No.
16 (Purple wire) and ground. If test light comes on, repair short to ground in Purple wire between IPC
and fuel gauge sender. If test light does not come on, replace IPC.