1991 check engine light codes....
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Nick1994
$100 site donor 2024
Originally Posted By: 01_celica_gt
Originally Posted By: Nick1994
With the older GMs, they're behind the crankshaft pulley.
A camshaft position sensor? That doesn't make any sense, would be near the camshaft not crankshaft, that would be the crankshaft position sensor
Duh! Can't believe I read that wrong, lol.
Originally Posted By: Nick1994
With the older GMs, they're behind the crankshaft pulley.
A camshaft position sensor? That doesn't make any sense, would be near the camshaft not crankshaft, that would be the crankshaft position sensor
Duh! Can't believe I read that wrong, lol.
The cam sensor is in the timing cover. This far out from 1991 you probably want to make sure the magnet is still in the timing gear.
JHZR2
Staff member
Are we sure the battery is ok and grounds are good?
For this drivability issue, ignore everything except 41 and 42.
38- you might have to press the brake pedal to cycle the brake switch through an off-on-off cycle during the test. If the PCM does not see a change in state=fault code.
Any time you see "circuit" in a fault description, look first to an actual fault in the sensor or the circuit (duh). Pull sensor look for damage (magnet flew off and killed it) or seal breakdown/oil intrusion. Many times a shot of brake clean will clean the terminals off enough to fix a code, likewise plugging and unplugging the sensor might knock off oxidation on the terminals.
CAM sensor errors normally manifest themselves with excessive crank times, or the need to repeatedly crank the engine until the PCM syncs up the signal randomly. Once the engine is started, the cam sensor signal is ignored as the crank sensor takes over and the PCM remembers the camshaft phase.
38- you might have to press the brake pedal to cycle the brake switch through an off-on-off cycle during the test. If the PCM does not see a change in state=fault code.
Any time you see "circuit" in a fault description, look first to an actual fault in the sensor or the circuit (duh). Pull sensor look for damage (magnet flew off and killed it) or seal breakdown/oil intrusion. Many times a shot of brake clean will clean the terminals off enough to fix a code, likewise plugging and unplugging the sensor might knock off oxidation on the terminals.
CAM sensor errors normally manifest themselves with excessive crank times, or the need to repeatedly crank the engine until the PCM syncs up the signal randomly. Once the engine is started, the cam sensor signal is ignored as the crank sensor takes over and the PCM remembers the camshaft phase.
Cap rotor wires and plugs, all the filters. Fix the wheel bearing and replace the burnt out bulbs. Short money if you can DIY. Tell your brother to do some moonlighting. A manual isn't a bad idea either. Good 'un D
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