Hey y’all, I need a hand figuring out where I messed up. I did rockers and lifters passenger side, along with intake upper and lower manifold gaskets and reassembled. Unfortunately, when doing the rockers my chain tensioner tool broke inside the engine. I fished out all but one semicircular piece about the diameter of a nickel. That piece I think fell down into the oil pan, my plan was to drop the pan and look for it, but I tried starting the engine first anyway.

On first start up it idled rough for about 3 seconds, then rpm’s began to drop as if stalling, before coming back up as I killed ignition. I thought it may have just been air in the fuel line from when I removed the intake manifold, so I tried again after priming the line a few times. Unfortunately, now it just cranks and cranks until the tip timer runs out and never starts. My battery voltage is running low now from cranking so much, but I hooked up a jumper and that didn’t change anything. Attached a JScan image of the codes it’s throwing, any guesses would be great.

 

Presume you are talking about the plastic guide you jamb down to push the chain guide rail back and release the tension. How the heck did that break to start with? ugh. I presume that you had no codes before this. If that is the case, knowing that something dropped down in the pan, I'd be a bit concerned by the P06DD code and thinking that is now restricting the pickup tube. I personally would have felt a giant kick in the balls if dropped something and would have not tried to start it until I had dropped the pan; however, that wouldn't cause the crank/no start issue.

I guess the most obvious question to ask is you didn't miss getting all the electrical harnesses connected good, right? Specifically the MAP and throttle body connections upon reassembly. Another obvious question but good to know for us trying to help.....you're 100% certain you did not skip timing, and you are 100% certain you did not accidentally set your camshafts near metal while you were changing your rocker arms (ie, the magnetic tone rings on the cams)?

If it were me, I would not do anything till i dropped the oil pan and searched for that object. I would note that at 10+ years and 120k miles, my 3.6L chain guides were losing bits and pieces, as well as the tensioner for the chain between the main crank and the larger chain sprocket (I ended up just rebuilding the timing altogether). Once I inspected the lower end issue, disconnect the electrical harnesses and reconnect them just to verify everything is good. I'd clear all codes and try one more time to see what comes back before moving forward. That would be my plan at least.

Initial troubleshooting on some of those codes is testing voltage to the harnesses, but with no reason that a voltage issue would have been introduced, I'd just disconnect things and confirm a good connection when reconnecting.

 

I appreciate the suggestion. I’ve spent most of the day diagnosing the dropped plastic. The pan was pretty seized, but it came off. Found the little piece I was missing in there. Tried to start again, and nothing, same as before. Then started disconnecting and reconnecting everything. Nothing. eventually went as far as getting into the valve cover again. After seeing everything was good, I reassembled and it fired right up. I’m sitting in here now as it idles just fine. My guess is dusty connection or something, I’m really not super sure.

 

Well that is good news at least. I can't tell you how many times I've taken off those damn valve covers. That passenger side is certainly not enjoyable at all!