Hey guys I am new to these forums and to the truck community and just wanted to ask a couple questions. So the truck has a check engine light with the cam sensor code and I replaced and it’s still on. So I figured I’ll just change out the cam instead. What would be a good baby cam for the truck, I don’t want it chopping hard, but a good bit and not harsh on the truck.Also I had a question about some aftermarket headlights on the RGB kits if anyone has it. It’s a “halo” kit but it’s just strips on the borders of the assembly inside Im guessing. But anyways thanks guys, any help and recommendations would be appreciated.

 

What is the code? It’s extremely unlikely that replacing the cam will resolve the issue.

Can’t help you on the headlights - aftermarket mods are not my area of expertise.

 

I don'y know what to tell you on the cam, @Gumby22 can proably help you though. On the headlights though, I just installed a set of projector HID's in my truck a few days ago and they are a major improvement over the factory units. I will post a little thread on those later today.

 

The code is P0340 for the CMP. And also I’m starting to think someone rolled the mileage on the truck because on the dash it marks 119 and on the report from AutoZone to check the code it says the next scheduled maintenance is at 205. That’s a pretty big gap so if anything it’s probably at like 200k but it runs fine. Also back to the cam, it does have a ticking noise when running so I’m assuming it’s from the lifters that’s why I wanted to change the Cam.

 

@OBSZealot Here is a thread I just made on how I installed my new headlights if you are looking for an improvement on your truck.

https://chevroletforum.com/forum/198...lights-107182/

 

The instrument clusters in these trucks are known for having problems related to weak/cold solder joints. There are several vendors that offer repaired or remanufactured clusters as well as new replacements; and you can’t exclude a PO ignoring a malfunctioning cluster for an extensive period of time or installing a salvage yard replacement either. It’s entirely possible the cluster has already been replaced/repaired and the correct mileage was never programmed in.

And, the same is true for the ECM. Although they aren’t as prone to failure as the clusters, they can be replaced.

Use the mileage at the time you purchased the truck as a determining factor for which mileage you should trust.

That said, you might also take anything that’s said at AutoZone with a grain of salt unless you know and trust the employees there. I’m not one to run down businesses in general, but of the many national chain suppliers in my area, AZ is my last choice.

As for the P0340 -

The reason this code sets is because the ECM is either not receiving a cam sensor reference pulse/signal or it’s receiving an erratic signal. The sensor can be fully functional but any problems with wiring, supply voltage and/or the ECM will cause this code to set because it’s generated as the cam rotates the distributor, regardless of any valve train problems.

Did you check the distributor rotor and shaft for free play when you replaced the sensor? The distributor shaft bushings/bearings can wear, causing the reluctor wheel (what the rotor mounts to) to wobble as it rotates and interrupt the signal.

You also need to verify the sensor wiring. With the key on, disconnect the cam sensor and check for battery voltage (or test light to ground) on the pink wire and ~0.02 volts on the pink/black wire. The brown/white wire may have 0.02 or 5 volts on it - I can’t recall if there’s a bias voltage on it or not, but having voltage on the wire indicates a good connection with the ECM.

If the sensor is getting battery voltage, and the terminals in the connector are OK, the sensor signal can be checked by back probing the brown/white (signal) wire with the engine running and at operating temperature. It should be generating 5-7 volts.

In regards to the valve tick - I’d check to see if it’s just a collapsed lifter before jumping into cam replacement. This is easily done by removing the valve cover and rotating the engine until the suspect valve opens, then watching for the valve to slowly close on its own without further engine rotation. If it closes, it’s the lifter. If not, the lifter can be pulled out for inspection.