So I’m in the process of finishing up my boosted 5.3 camaro build. I am running a 2000 Silverado computer (24x), running the stock LS1 wiring harness from my camaro (2002) and I swapped in a 2005 5.3. When I built the engine I swapped in a new cam and crank sensor. The engine has a btr boost cam in it (226/231 113+4) my car starts hard and cranks forever on a cold start or whenever it’s been sitting for a long time. After I’ve driven it for awhile it start fine. Car idles rich and runs rich. The car is on a very basic base tune for the time being until I get this figured out. Car is throwing a P0342 and P0343 code. My cars Tachometer also does not work.. but when I put the obd2 scanner on it it reads my rpms fine but not on my gauge cluster. My gauge worked fine before I pulled the old engine. Idk if this is a tuning thing for the cam sensor not reading or what but the sensors are brand new. My harness isn’t all messed up the wires look pretty solid. My grounds should be all fine. Pcm I hooked up. None of the pins are messed up. Not too sure what to do here. I need some advice.

thanks

 

And to add onto this.. is this just going to affect my car when it’s trying to turn over or is it always gonna be throwing my timing off like while it’s driving and if I’m making a WOT pull. Like if it were to go back to the dyno like this.

 

As I understand it, the cam sensor will only affect start up - so the engine knows what cycle it's on. Bad cam sensor leads to long cranking times but once started, all should be the same.

 

Cam sensor is used for injector timing/triggering. See below for details. It can induce long/extended crank issues. Did you install a 3 bolt cam? If so, did you happen to notice if the new cam had the reluctor at the rear?Connect fuel pressure gauge to confirm pressure is not low/bled off after sitting. Did you install factory or aftermarket cam sensor? Swap in original to test? Verify 12V and gnd at sensor and sensor output signal at PCM? CIRCUIT DESCRIPTION
The Camshaft Position (CMP) sensor works in conjunction with a 1X reluctor wheel on the camshaft. The Powertrain Control Module (PCM) provides a 12-volt reference to the CMP sensor as well as a low reference and a signal circuit.

The CMP sensor determines whether a cylinder is on a firing stroke or on an exhaust stroke. As the camshaft rotates, the reluctor wheel interrupts a magnetic field produced by a magnet within the sensor. The sensors internal circuitry detects this and produces a signal which the PCM reads. The PCM uses this 1X signal in combination with the CKP sensor 24X signal in order to determine crankshaft position and stroke. This diagnostic for the CMP sensor checks for a loss of CMP sensor signal.

Observe that as long as the PCM receives the CKP sensor 24X signal, the engine will start. The PCM can determine top dead center for all cylinders by using the CKP sensor 24X signal alone. The CMP sensor 1X signal is used by the PCM to determine if the cylinder at top dead center is on the firing stroke or the exhaust stroke. The system attempts synchronization and looks for an increase in engine speed indicating the engine started. If the PCM does not detect an increase in engine speed, the PCM assumes it incorrectly synchronized to the exhaust stroke and re-syncs to the opposite cam position. A slightly longer cranking time may be a symptom of this condition.

CONDITIONS FOR RUNNING THE DTC
The engine speed is less than 4,000 RPM .

CONDITIONS FOR SETTING THE DTC
The PCM detects the cam signal is stuck low when the signal should be high for 1.5 seconds .

ACTION TAKEN WHEN THE DTC SETS

• The control module illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
• The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

 

yes it’s a 3 bolt cam and has the reluctor wheel in the back. I have a new sensor and the harness works fine it’s getting power .. worked great when I pulled the original engine. Grounds are good. I wonder if I’m not getting cam position signal because of the tune or what but if it’s just affecting my start up I am not too worried but would like for it to be fixed. Could be a pcm problem.. but I’m going to test that later today.

 

Also probably doesn’t help I’m on e85 so the coldstart is gonna be longer as is..

 

If you were to go WOT now, does the engine shut down? Have you performed a crank relearn procedure? Also - I was just reading the following thread, if you're confident on the grounds maybe just check where your sensor mounts and make sure it's clean . https://ls1tech.com/forums/pcm-diagn...f-voltage.html

 

if I go WOT the car stumbles because it goes lean cause the tune isn’t anywhere near done.. as soon as it’s about to make boost it goes lean. Just a super basic tune rn so I can drive it normal.