I've been working on my buddies car, we're having a issue, when we start it up we can hear it hit the top cam sensor. Either is it cause by bad timing tensioner or bad timing guides?? If it's not cause by either or those can anyone give me any pointers

 

Also a really worn/stretched chain.
I would just replace all of it.

But, if you have to piece it....
I think I'd pull the rocker cover, check the chain slop (with the tensioner engaged)
Then pull the tensioner, then Cam Gear, suspend the chain and pull/inspect the guides.
Then if nothing is obvious, look at the chain itself.

 

We took the car to another buddy semi local because this is over my head , I could just replace the whole topend but what if it's a crank issue ?
so I gave my buddy my extra stock cam I had , cam gear and bolt , new cam sensor amd went out to another buddies and grabbed his cam locking tool to to go give to other dude..lol.
I haven't been able to do anything really with my own cars but I can now though...
So far From the pic i was sent , he hasn't gotten much further until car cools down fully but from the looks of it , it looks like the cam gear is bent. And I'd attribute that to a loose chain and that would be caused by a failed tensioner or timing guides , I'm leaning towards tensioner because awhile ago I told him to replace it to be safe because on cold mornings at cold start , you could clearly hear the timing chain rattling..ooor his cam bolt backed out and the cam gear got loose.
I can't make people do the work but I did highly suggest he do it befor hed done anything else and ,well yea, he didnt... but that doesnt matter..
I just hope it nothing terminal to the engine. I hope worse comes to worse it can be fixed with the parts I'd given him and a new timing kit I'd told him order now.
I will keep you posted..

 

It's ok to name names. Hah.

Cam bolt was loose, which likely allowed the cam gear to wobble, which broke the cam sensor and either pulled or allowed the alignment pin to fall out, which subsequently got jammed between the gear and the cam itself. Timing is still exactly where it should be. I can't figure out how the gear didn't spin independently of the camshaft. Super lucky. Photos below.


Cam tool installed to show just how crooked the cam gear is.

Alignment pin missing

Alignment pin found.

 

Makes sense, any chain/tensioner problem should have been really noticeable to do cam sensor damage, but... I've seen people continue to run there cars with all sorts of apparent issues.

Good that you found the issue, make sure you clean the bolt threads and loctite it.
Also do some more investigating, unless they were not tightened properly, Cam bolts usually don't loosen. Only thing I can think of is some sort of imbalance or vibration in the Cam, to cause it to loosen, without any recent work and improper torque.

 

I believe the cam bolt wasn't torqued correctly when shade tree mechanic did work on his car in the spring , after I fixed a bunch of stuff and upgraded the car it began running good and making more power but soon as it did it backed the cam bolt out then.
luckily I had my old stock cam , gear and bolt and even a new cam sensor. Then he put new timing components in too and the car now running better than it ever has he said..
So I'd like to give a big thanks to Dan for taking the car in on such short notice and getting it back on the road for him..
BTW it coulda come loose from bad serpentine system because id found his ac compressor on with 1x bolt and was wobbling around and it also destroyed his crank which was almost completely separated too..
I bet those issues caused the bolt to finally loosen due to improper tightening. Then after i got it all running well he was out , enjoying his newfound power and unfortunately it found the weak spot..