Temporary ticking from cylinders 5 or 6 on startup

[Uwon]

2006 Carrera S, 130K miles mainly long distance, no track nor autocross.

As noted in the topic, above, I have a ticking noise only on cold startup which goes away as soon as the coolant reaches about 90F. My first thought is sticky cylinders 5and/or 6 valves in which case what would be the best additive or procedure to diagnose (confirm/eliminate) this condition.

I change the oil and filter every 4K miles and periodic oil analysis by Blackstone shows no unusual activity.

Obviously, my ultimate concern would be bore scoring.

thoughts?

TIA

Johan

 

 

Edited February 27 by Uwon

[JFP in PA]

I would be bore scoping those two cylinders looking for bore scoring..............

[jchapura]

9 hours ago, Uwon said:

2006 Carrera S, 130K miles mainly long distance, no track nor autocross.

As noted in the topic, above, I have a ticking noise only on cold startup which goes away as soon as the coolant reaches about 90F. My first thought is sticky cylinders 5and/or 6 valves in which case what would be the best additive or procedure to diagnose (confirm/eliminate) this condition.

I change the oil and filter every 4K miles and periodic oil analysis by Blackstone shows no unusual activity.

Obviously, my ultimate concern would be bore scoring.

thoughts?

TIA

Johan

 

 

Is there any up trend in wear metals?

What temperature zone has the car lived in? 

Any unusual oil consumption? 

Do you have sooty tailpipes? 

Inspect the spark plugs, anything oil fouled? 

If you remove the spark plugs, you can do a borescope but it might be less effective than one done via the sump. 

If you remove the spark plugs, you can do a compression test to see if rings or valve guides might be involved. 

Any pending engine trouble codes?

What oil do you use?

 

Edited February 28 by jchapura
Another another question.

[Silver_TT]

The best procedure would be to drop the sump and inspect the cylinders with a bore scope.