P 1391 engine code, 2002 wrangler - 2002 Jeep Wrangler

SOURCE: engine keeps missing. unknown codes

Code 1682 indicates low battery voltage. This could be a problematic alternator, which would likely cause misfiring. Autozone should be able to check this for you for free.

Code 1391 indicates the computer can not see the crank or cam sensor signal. This would likely be a result of the misfires.

Code 0320 indicates the crankshaft position sensor reference signal could not be found while the engine is cranking.

All of these issues point to either a cam/crank sensor malfunction or a charging system problem, either or both of which could cause the misfiring.

SOURCE: 2002 jeep grand cherokee with 4.0 engine will die but restart

p0340 is the cam shaft sensor, this will cause it to cut off while driving, hardtime starting, p0351 is the ignition coil A primary/secondary curcuit mal function. p1391 is ignition system misfire, this could be plugs, wires, or coils. first of all have the cam sensor changed and it may correct the rest of the codes. when fixed turn light off with obd2 scanner. if you do not have one, then any auto parts store will erase the codes fo free of charge.

Wade Mobley

• 513 Answers
• Posted on Dec 03, 2010

SOURCE: i have a 2000 jeep

it does sound like the ecu is bad the only other thing it could be is the antitheft system is having problems

SOURCE: 98 wrangler shuts off and

(this is for others who may be viewing this problem)
P1594 = charging system voltage is too high
P0320 = crankshaft position sensor (CKP)/engine speed (RPM) sensor-circuit malfunction
P0463 = fuel level sensor circuit, high output
P1391 = intermittent loss of CMP (camshaft position) or CKP (crank position) sensor

Probably start with changing the crank sensor. But keep in mind that the high charging system voltage may be causing the other electrical sensor problems. The voltage regulator (probably located internally in the alternator) is not regulating voltage properly. So changing the alternator may be needed as well. Price the parts and start with replacing the less expensive first.