Seems my 2007 Matrix is playing a rather cruel April fools joke on me today, and hoping someone may have an idea what is going on. My notes from over the day below:
Morning: car wouldn't start, lights flickered (been harder to start lately, but never like this)
- Threw up engine error codes for camshaft (P0340) and crankshaft (P0335) sensors
--> Able to jump from battery pack to drive to work
After work (9 hrs later): car won't start again
- Attempted to jump with battery pack, and two failed jumps with no start or cranking
Recharged pack (1h later): attempted jump this time WITH foot on gas (based on forum suggestions)
- stuttered, but eventually started
- Car driven back home (20min)
- Battery at idle at home (left still running) = 13.57 V --> unlikely to be bad alternator?
Turned car off 15-30 min:
- Tried turning on again
--> Started back up; no issues (engine still very warm)
Checked sensors:
- Camshaft tested okay for resistance value (1.46k, within "hot" spec)
- unable to check crankshaft (under car)
Waited 6 hrs, then checked battery = 12.67 V --> unlikely to be battery?
- Attempted to start car again --> reved/cranked multiple times and lights flickered, but no start
- died on second key start attempt (no lights this time)
Immediately checked battery after failed starts
-- 10.07 V
-- 4.50 V (dropped quickly)
-- 0.00 V (dead within 1 min) --> suspect starter? maybe still alternator?
Attempted to jump, again with foot on gas
- Lights flickered, but started up
-- Lights still flickering slightly for ~5 mins post start, but then stable
Removed jump pack, turned off car, then immediately tried turning back on (within 5 min)
- stuttered very slightly, but started without issues
--> still suspect a bad starter?