Timing chain to big

It's a BIG job. It requires removing everything from the top of the engine (intake manifold, throttle body, all plumbing, valve covers) then removing the harmonic damper, most of the accessories, and then the timing cover. That's just to get to the timing chain. You have to remove the chain guides and tensioner, then cam gears and crank gear. If you're going this route, also replace the two chains (intake cam to exhaust cam) on top of the heads, the water pump, and the tensioners. Be very precise in reinstalling the three timing chains so that everything is in time.
The link shows the details of the chain itself, but be aware that your engine is packed into your Intrepid with limited work space in some areas.
Chrysler Sebring Concorde 300 2 7L timing replacement Cloyes kit 9 0397SA

u may need 2 replace the timing gears as well old gears may have worn teeth.i had same prblem with a chev mtr fitted a chain&gear set fixed it right up. ps make sure u use a new chain

I really hope you know what you're getting into.....Big & detailed job. I went on and posted the instructions as far as removal and installation of the timing chain. There is a whole other section that you need as far as removing the oil pan and strainer but way to much to post on here at this point. Anyhow, it's a 2 piece oil pan and just to let you know alot of the parts like the timing chain cover, oil pan, the cover on the timing chain cover does not have gaskets and Nissan doesn't either. You have to use some RTV and don't go cheap, get the good stuff because all the work that is involved in this you don't want to have to repeat because of a leak. Also the oil pump is in the timing chain cover and Nissan has had some problems in the past with them. I would suggest going online and finding a new oil pump that comes pre-installed in a new timing chain cover. You can pick the whole assembly including the cover for about $150.00 and worth it. Wish you were here I have one ready to go. Anyhow, email me at [email protected] and what I can do is send you the engine management section of my service manual in a PDF so you have the info on the oil pan removal.....You need it. It will also have all the stuff I am posting below so you can make it big enough to see or even print out if need be and no there isn't a cost for it. I'm in a good mood....lol. I hope this helps. Here is the timing chain instructions for you.

If you have replaced the timing chain please disregard my answer, I'm risking my rating because I want to help you for free.
If the timing chain has not been changed that the problem might be an overstretched timing chain.

As timing chain accumulate mileage, chain stretch, sprockets wear out, and set the valves off timing. Most chains go up to 100000 miles or more, but not always. As a rule when there is more than about half inch of play between the gears on a V6 or V8, it is the time for a new timing chain and sprockets.
It is not unusual for a timing chain to accumulate 200000miles, but I remember a car, with broken timing chain, with only 160000miles on it, the valves were bent and a hole was put on the piston.

Signs of worn out timing chains are:
Rough idle.
Sluggish performance and poor economy.
Sudden engine performance change including the inability to start the engine.
Intermittent backfire through the intake manifold.
Inconsistent ignition timing or a clattering noise coming from the front of the engine.
It is a good idea to replace the water pump (coolant pump), and the thermostat while replacing the timing chain.
The cost of the replace of timing chain is at least +$1300, but if is to bad, we pull out engine and replace both guides. In this case might cost more.
Please do not be mad with me. I'm a certified dealer, and I'm trying to give you the necessary information to help you to deal with the problem.

Same as any other v-8 dis-assemble the front of the engine to get to the timing cover. Loosen the oil pan bolts to allow the timing cover to be slipped out. unbolt and remove the timing cover. Turn the engine over by hand until the dot on the crankshaft gear( the small one) is at the top 12 oclock position, and the dot on the cam gear(large gear) is at the bottom 6 oclock position remove the old cam gear and old chain. Install new gear and chain with the marks in the same places. Re assemble engine. DO NOT be tempted to just put in a new chain, replace the chain and cam gear as a set, wear on the cam gear will cause the chain to be slack, which in turn causes the cam timing to be late.

This is like a big job.....You would do better to get a repair manual for less than $20/copy.

Disconnect your battery.
Line-up the crank-pulley up; camsaft up.
Remove distributor
Drain the coolant, remove water-pump, crank pulley, alternator, compressor-to give more room.
Remove the timing-chain cover.
Loosen the tensioner
Remove the cam-sprocket, and take off the old chain.
IRemove old gaskets.
Installation is reverse of removal. Crank-pulley and camshaft marks must be in proper positions, otherwise engine would damage.
**To avoid serious engine damage, let a shop do it!

i purchased a new timing chain set and the cam pickup was bad on the new cam gear and we had a no start problem. i took the valve covers back off put the old gear on the cam and it started. BUT be careful if u do that you have to wedge the timing chains apart before you remove that gear so the hyd adjusters do not over expand. 4.7 dodge engines **** BIg they made them trying to save gas but the parts and repair over-ride any gas saving i got.

If it has not broken or jumped timing you simply remove the valve cover and timing chain tennsioner. Then cut a link out of the old chain on top of the cam gear, then you attach the new chain with the supplied master link and slowly rotate the engine until the old chain has run out and the new chain is in it's place. It's best to have a helper to rotate so you can hold the chain against the cam gear. Once this is done recheck the can timing and do not let the chain slip or you will have to pull the injection pump and retime it. Even if you do it's easier than removing the front cover! Good luck!