Im stumped... I finally finished swapping the motor on my 06' Z06 and went for a first cruise the next day after getting the car tuned when the car started to misfire and threw a P0335 code (crank Sensor). The sensor was new when I put in the engine (2 weeks ago and not even 10 miles) but I replaced again just in case it was a faulty sensor. Same issue. I then verified that the reluctor wheel wasn't spinning with a screwdriver. The car has Cylinders 5, 7, and 8 that are cold and the rest are hot. It appears to be getting spark as well and no blown fuses, Injectors are brand new from FIC. Checked all grounds on the chassis and power wires as well. I got my multimeter out and recorded the voltage from the pins in the pic below. Any ideas on what this can be? Honestly at a loss on what to check next...

Fairly new to the C6 platform and not the best at diagnostics so I appreciate any insight.

 

When a new crankshaft position sensor is installed, you must perform a crankshaft position relearn procedure. Did you do that?

 

I do have access to a tech 2 but I haven't done a crank relearn before, any walkthroughs on how this would be done using a tech 2? I know how to read DTC's and read some data using a Tech 2 but what menu would the crank sensor relearn be under? From what I read this could be done on Gen 3, but I don't see much info on the tech 2 crank sensor relearn with Gen 4 stuff.

 

I haven't done the relearn myself, but I know you have to go to the Special Functions menu, then Crankshaft Pos. Variation Learn. Then just follow the on-screen steps.

 

OK, so you should do a crank relearn with the Tech 2 and it should be in Special Functions...basically left foot on the brake and with your right foot on the gas accelerate to 4500 RPM or so I think...it will tell you in the testing procedure...not doing the procedure will not throw the P0335...the CKP wiring is a little different than my C5...WOW...yours uses a 5 volt reference and is a "pull down" circuit design...mine is a 12 volt "pull up"...your 5 volt signal gets pulled down to ground from 5 volts through the CKP sensor...now you checked the CKP ground but "open circuit" voltage testing or even resistance testing with an ohm meter of a ground is not the right way...if you have an incandescent (not LED) test light (the incandescent draws only about 300-400 milliamps) connect it to battery POSITIVE and touch the tip to yellow/black low reference or ground...light should be bright...did you use an OEM sensor ??...if not you should install one...seen way to many bad "new" aftermarket ones...with your test light you can also do a "bypass test"...with the connector INSTALLED and if you can get to it in that horrible location backprobe the signal wire with a T pin or even a needle if you have one and with the test light connected to a good ground tap the signal wire T pin quickly a few times with the tip of the test light with the start button in the ignition/on mode...with the test light you are acting like a crank sensor...you may hear the fuel pump turn on and the fuel injectors fire...if you hear this the signal wire is good to the ECM...with the Tech 2 if you look at the Data Pid called "CKP Active" counter if I can remember correctly and with a good signal to the ECM the counter will increment up while looking at the scan tool while doing this bypass test...as far as the 3 cylinders misfiring and verified with the Tech 2 you will need to check if you are missing fuel or spark...for spark just remove the plug wire and make sure the spark either jumps to the engine block...I just use that 12 volt test light connected to ground...let the spark jump to the tip of the test light as you remove it from the coil pack...if not I can show you how to do a coil pack functional test...just need a T pin, test light and a volt meter...as far as the injectors make sure that those 3 (5,7,8) have 12 volts on the pink wire with the engine in ignition/on mode with the injector unplugged and to make sure you have injector pulse or "control" connect that test light to battery POSITIVE and with the engine running probe the other striped wire with the engine running...if you have injector control the test light will "blink" if you have good control...the ECM grounds that striped wire...if you want to let a shop handle this I know of a great diagnostic shop in Pasadena...shouldn't be too far away.

 

Might not be the cause of your problem but it never hurts to at least rule it out - disconnect the main connector (the one that powers all 4 coils) for the coil packs and make sure none of the pins got pushed down, even a little. A few years ago I had a misfire that I simply could not solve and this turned out to be the fix.

Also, a crank relearn most likely won't help you. I've swapped engines dozens of times over the years in 6 different C6s and never once have I ever done a relearn or needed to.

 

Update, swapped to an oem sensor and the problems went away for a day then a whole new set of cylinders are misfiring. Also, did a crank sensor relearn and unplugged coils and checked pins but no luck with any bent. Anyone know where the crank sensor gets it ground from? Any specific ground on engine/chassis thats attached to that part of the harness? Any other insight or help is appreciated.

 

The three values shown on the electrical connector diagram are all positive voltages, so that leads me to think that the CKP must get its ground through its mount on the engine. In that case, the ground connection between the engine and frame is pretty important and needs to be clean and tight.

 

The CKP ground is your “low reference” pin B…low reference grounds go to the ECM…you have to check your coil packs with a test light and a DVOM…”looking” at wiring doesn’t cut it…you’ll just be chasing your tail…so you have a whole bank misfiring now ??…the coil packs have 4 wires…power, 2 grounds and a control wire…if you backprobe the control wires and apply 12 volts to each the coil packs will fire the plugs…each coil pack draws about 4 amps…normally all 4 coil pack grounds on each bank are tied in together.