I recently had a couple camshaft bearings spin on my 12v B5 A4. For good measure, i replaced the entire motor. I just started the new motor today and i am having a bit of noise coming from the motor. It sounds like the injectors ticking but a bit louder. I am thinking it is a lifter or one of the knock sensors that are not properly clipped in.

Does anyone have any advice for me?

 

thats not something that can be diagnosed over the internet. if your cams were toasted i would have just bought a new head instead of the entire engine, you would have saved yourself alot of work.

what did you replace it with? a used engine? do you know the pedigree info on the replacement engine? you could have just replaced one bad engine with another. thats the gamble when buying used parts.

the ticking could be anything from sticky lifters not getting enough oil pressure, possibly from some oil sludge, to a bad cam chain tensioner or anything in between.

it could also be normal, theres always a little tick just from the moving parts in there. depending on what it sounds like a good mechanic could tell you what it is, but not over the internet. btw knock sensors dont make noise.

 

Ghost, you are correct, I could have saved myself a bunch of work by just replacing the heads and cams.

However, I found a great deal on a low mileage motor from a friend, and yes I know its pedegree.

I was not looking for a diagnosis, rather a general discussion of what possible probelms are.

PS: Correct! Knock sensors dont make noise! Thats why they are knock SENSORS. I was merely suggesting that they were not properly sensing a knock and correcting for it. A good mechanic told me that. (me)

 

To check the knock sensor, unplug the sensor, turn on the ignition and check the reference voltage. It should be between 4 and 5, sometimes up to 6 volts. Turn the car off and check the sensor's resistance to ground. From a reference chart I found, most knock sensors are between 3.5-4.5 kOhms (3500-4500 Ohms). Additionally, check the torque of the fastener. I can't find a chart on that, however.

If you have a VAGcom, you can check the timing adjustment or knock signal by running the car and rapping on the exhaust manifold with a wrench.

And for the record, you probably saved yourself work by swapping the motor. Damaged cam bearings are usually caused by oil-starved valve trains. If you had replaced the heads, you might have been fighting clogged passages and seemingly infinite pesky metal shavings!

One last thing, I recently was told Seafoam can be used as an oil treatment. If you have a sticky lifter, it might help clean it up. Run Seafoam on the intake to clean any possible carbon deposits and then run it in the oil to clean up the insides.