I just got into an 01 s-type 4.0 with 63,000 miles this week for a good price but it needs work. It seems like it needs a cylinder head, there is a loud taping on the top end almost feels like its hitting the valve cover on the passenger side. I am in the process of finding a rebuild shop in my area but the car is idling rough and the transmission doesn't go into drive unless you put in 2nd gear first or rev the engine while in D so it engages. My question is will a bad head with a loud tapping cause the other problems with the shifting and transmission and the unstable idle? Or should I just take it into a dealer for diagnosis before spending the money on parts?

 

If you have the tools available, you may want to remove the RH cam cover and look at the upper timing chain tensioner. Most of the 4.0 Litre engines have had them replaced, but it is good to see if the tensioner body is made from plastic, which must be replaced with the updated metal version.

From the description of the noise, you should also have a compression test done to determine if there is a physical problem with one of the valves as that would require removal of the cylinder head. The RH cylinder head can be removed with the engine in situ, so it is possible, but given the age of the vehicle, it may be more cost-effective to simply find another engine to swap in.

If the gearbox is having trouble getting into gear, the fluid level and condition should be inspected prior to any other work being done.

 

Thanks for the info, I will send it to the dealer for a diagnostic on the transmission I'll have them check on the compression as well.

 

As for the transmission, if it is shifting properly any other time then you may have a cable adjustment problem or a bad shifter selector switch.

 

it drives pretty smooth except that the engine feels like its off and it does hard shift out of third but there is something seriously wrong with the engine. Ill have it at the dealer after Christmas to see if they can tell me before i get into the bank and start pouring.