Background: 99 A6 2.8L 200K miles well cared for. 2 weeks ago i kept getting flashing oil symbol on the dash, pulled over checked and oil level fine and it turned out to be sensor was going bad. Ordered new sensor but before it could arrive I hit a chunk of concrete on the hwy and cracked oil pan in 2 places. Well I didn't know the pan was cracked and loosing oil, I though the impact just jarred the sensor. 2 miles down the road when I pulled into my driveway I could feel something was wrong and shut down. After I stopped another quart drained out. BAD LUCK.

So we pushed it into the garage, put a new lower oil pan on, filled with oil ran for 5 minutes (It took a good minute to get it to start, once started had a really rough idle) then I drained into a brand new catch pan. Shined a super bright light in the oil to see how much fleck was in there. Not too much in there.

Drove it around a little and flushed oil again, not much more metal fleck came out, but idle did not improve. So I started checking things...

Compression check: All cylinders are 180-185psi
Vacuum gauge (at intake manifold T into blue connector) 8" and fairly steady on a large diameter gauge.

So as far as I understand good compression and low manifold vacuum is timing is off. I took it to a europsport shop to plug into laptop. Misfire cyl 4,5,6 (Bank 2 Drivers Side U.S)

Pull off valve cover to find the top plastic guide on the Cam tensioner has been chewed. I pulled pieces out.

I decided to order timing belt, water pump, thermostat, gaskets and seals since I was digging into the car this far.

Replaced Bank 2 Cam tensioner with a new one after pulling both exhaust and intake cams out. Chain links = 15.5 roughly on drivers. side.

Bank 1 was fine, and had no intension of touching except with a mirror I could see leaking behind on the seals. WHen I tried sneaking the half moon seal and metal gasket under the tensioner the stupid tiny mesh filter fell out. So I removed both exhaust and intake cams on Bank 1 as well. replaced plastic guides and filter, plus all seals and gaskets. Chain links = 16 exactly.

In order to secure the cam caps I allowed the cams to rotate counter clockwise approx 15deg so the lobe was pointing straight into the lifter. (IF i set the cams correct, I could't get the #4 cam cap started without fear of initial thread damage. ) Once I snugged the cam caps I used the CAM alignment tool to rotate the cam clockwise to correct timing position. no interference was felt other than from number 4 exhaust cam lobe

So with all cams set correct and timing belt plus everything else installed i rotated the engine using 24mm 12point socket on crank 4 times. I was easily able to reinstall the CAM BAR meaning the timing is correct as far as I understand. (I guess it just guarantees crank to exhaust timing).

Put it all back together, hook battery back up and the car starts right up. no check engine light, cold high idle fine. Once the idle drops it is a rough idle. UGH!

I have run the car for 20 minutes, no check engine lights. It is dead smooth from 950 rpm's up.

new spark plugs installed (NGK) at beginning of job


I recheck vacuum and now it is only slightly higher than before at 10"!!!!!!!!!!
I checked and I did plug the secondary air pump back in.
Confirmed Vacuum connections were made to the valve covers...

I AM TOTALLY LOST AS TO WHAT THIS COULD BE. If I had a bad lifter the vacuum gauge would fluctuate when it got to that one. THe gauge is very smooth.

I swear it has to be something stupid. I haven't finished burping coolant yet, but I doubt it would cause this. I have lots of pictures if need be to try and solve this..... If I did damage the head (valves etc) how could I still have good compression??

ONE MORE CLUE POSSIBLY: THe engine sounds different now when I turn to over before it starts. Different than it has ever sounded in the past. Not sure if the computer was unplugged how long it would take for things to adjust?

Thanks in advance!

 

Simple thing to try... Throttle body alignment... Disconnect the battery. Wait a few minutes. Reconnect. Turn the key to on position without starting the car. Wait a few minutes. (You can actually hear the throttle body doing its thing.) Once done, start the car and see what happens.

 

Ok I'll try that right away tonight when I get home.....

 

I tried it as soon as I got home tonight. Disconnected battery. went in and had dinner, came out and reconnected battery. Then turned key to on position. Throttle body made weird noises for approx 30 seconds then quit.

Car wouldn't start... It turned over straight for 15 seconds. went out to inspect engine compartment to find i hadn't plugged in MAF or other connector at the air box (although i don't know if that was cause. key off, key on after a little bit it would fire, stumble and die after achieving about 300rpm. After about 15 times of this I depressed petal to floor and got it to go. it sounded like it was running on 5 cyl for a few seconds then took off.

It was flashing Check engine during this phase (i assume active misfire).

Am I to believe now my timing is STILL off??

 

Responded to your PM...

 

When I was resetting the throttle body, I noticed the fuel pressure regulator vacuum hose was broken in half. So I went to dealer and bought 2 meters of the braided 3.5mm I.D. hose and replaced ALL the vacuum lines. Car started better and runs much better than before but still has a slight shake when sitting in the seat.

I hooked up the vacuum gauge again and now I am up to 14in vac at intake manifold. Green is 15-20. If I bump throttle to 950 rpm I am at 17in and smooth as silk. Note: the needle is very smooth on the gauge, no bouncing.

So I pulled the valve covers back off and set crank to TDC. Bank 1 marks are lined up perfect and the tensioner (original with replaced pads) is sitting up above the 2 metal prongs (guides).

Bank 2 (drivers) the exhaust cam is lined up perfect, but the intake notch is about 4mm to the left (toward intake manifold) of the arrow on the cam cap. I also notice the new tensioner I put in is sitting low. Well below the 2 prongs.

This must be my last issue. But I don't know what to do about it. I am sure if the chain was sitting at the proper height the intake mark would be on the money. Could I have done something wrong installing the tensioner? Do you have to prime a tensioner?

When I thought the engine was toast I put rotella T 40 weight in the motor, would that cause this? I was planning to swap back out to synthetic when done...

Thanks for any help!!!!


EDIT: So I went back out put tensioner tool in Cam tensioner with oil sprayed on the main shaft. It appeared to be dry compared to bank 1. After moving tensioner up and down a couple times with tensioner tool... It now seems to behave like bank 1 tensioner while rotating crank.... They both bounce up and down when I try and turn crank... That being said it still appears the new one I put in the main shaft that goes up and down doesn't get any oil on it.... If I look at bank one it is well coated with oil....

As it sits now timing looks pretty good... exhaust cam lined up perfect, and depending on how the tensioner sits when i rotate crank, intake notch varies from being right on the edge of the triangle mark to 4mm off the mark. The only thing I can think of is to rotate intake cam back 1 tooth so I get closer to 14.5 roller links?????

Here is a link to pictures.....

https://www.icloud.com/photostream/#A15qXGF1uzs6E

 

I shared this with another guy long time ago.



I know that some cases the cam mark doesn't line up with the peak of the gear tooth.

Anyways, you mentioned that it is 4 mm off. 4 mm off to the intake side or the exhaust size?

 

One more thing... Don't go by the triangle marks. Go by the cam markings.

 

the intake cam is off 4mm towards the intake manifold.

What did you mean by go off the cam marks not the triangles? I thought the cam notches needed to line up with the triangles on the cam caps.

I have 3 of 4 cams lines up dead nuts. just the intake cam is a bit off. It was off the same way when I took it apart initially, but i attributed that to the top cam tensioner pad was gone.

 

Once the exhaust cams are lined up by the lock bar, your intake cams can vary in their positions a bit based on the tensioner position. Once the exhaust cams are lined up, then count the lobe between the cam notches, not the triangles on the cam caps.