The good news is it runs better than it has in quite some time. The question is why.

After I had the cam chain tensioners replaced 1 1/2 years ago, the motor always seemed sluggish to rev, but no CEL. It was to the point that I thought the cam timing was off a tooth.

The flappers in the intake are free; I had a stuck one a few years back and was able to free it by spraying the end with carb cleaner and working it back and forth. One still seems a bit slow to return when the vacuum hose is attached, but moves free when its disconnected. The pass side.

I also have the Gruven alum ams in place. I recently put some Rislone engine cleaner in it because one of the cam followers makes noise at idle.
My theory is either one of the flapper valves started working better, coincidently right after I washed the motor or the cam tensioners which are also the variable mechanism are working properly. The low, to mid range torque is awesome. No real need to rev past 4,000 in most situations

Any comments welcome, but I am happy enough to keep it and redo the front end and leaky oil cooler tube. Oh and it's an auto.

thanks Ed

 

When I got my 2002 4.2 it was really sluggish. Only after I replaced all the spark plugs, coil packs and the MAF (was throwing an intermittent code) it really took off. I've had this car now for almost 6 years and I still love the v8 - worth every penny I threw at it

 

Edo,
Check to make sure your cam chain tensioners are positioned on the correct bank. If they're like the 2000 A6 2.7, then they look alike & fit on either side, but there are unique p/n's for each bank. If they have the wrong p/n's on a side, or both, then it will mess with the engine timing.
For my son's 2000 A6 2.7, the PO switched them L/R vs R/L & we chased misfire problems until I found this switch-a-roo.

 

I checked the bill. There are two part numbers, so I will have to look tomorrow to see what's up. Sheldon, oddly I did replace one coil a few months back. May need to be proactive after I get the front end taken care of. I just got depressed look at the tie rod bill. $182.00 for one complete inner and outer, $110.00 for just one *&^%$ end. That's almost $300.00 towards the kit that includes these. Needless to say, that shop won't receive any more business

 

The tensioners are ,thankfully, are the correct banks. Another thought came to me as well. I have run 10/30 oil in the summer. recently went back to 5/30. And, ironically, ran across an article about why not to use a heavier oil, because of the possibility of the smaller oil passages in things like the adjusters. Anyone want to share what weight they are running. Not necessarily looking to debate about the conv vs synthetic debate or even change intervals. I stick with about 5000 because I saw what the 10,000 did to the inside for the first 50,000.

thanks

 

I thought our C5 4.2 cars are only approved for Xw-40 oil.
Anyhow I used to get 10w40 for the summer and 5w40 for the winter. Within the last 1.5 years however I switched to 0w40 (mobile1) for any season. It is VW 502 00 approved for what it's worth.