Vectra engine tapping problem.

[benny3008]

Hi, We've replaced the head on a Vectra b 1.8 SRI (X18XE) due to a tapping noise in the top end. head replaced fine, no issues, timing smack on, but there was a tapping in the new head too. we replaced the cam followers, we had a choice of 16 from new head and 16 from old head so used all the cam followers that were in good working order. But the tapping is still there, we have checked the compression on all four cylinders which is within tolerance, camshaft clamps are all in correct places etc... but we still cant figure out what the tapping is, it's definitely in the top end and is fairly loud, acceleration is slow which is what made me thought it was valves. Please can someone give us any suggestions as to what it could be, I'm wondering whether it may be the cam followers not seating correctly or if one of them has collapsed however the noise is more frequent than for it to be just one cylinder. That said, it seems unlikely to be followers as the chances of all of them going within such a short space of time are low surely. Please, please, please someone help!

[benny3008]

forgot to mention, once the engine has warmed up, it starts to misfire slightly.

[ChuckFickens]

Sounds daft..... but check the exhaust manifold for leaks or cracks as that causes a tapping like noise and will throw the ECU out due to air being sucked into the exhaust.

[benny3008]

okay, will check that, thanks, i have just had the car running fro quite some time, the noise did get quieter after a while, it was still there but faint! it only came back on acceleration. the slight misfire was still there though, could this mean oil pump problems?

[chas2008]

could it be poor oil feed ?

[benny3008]

thats what im thinking now chas, I have just started taking the oil pump off to replace it as we have a spare anyway. had to stop though as it started raining. :-(

[TWR]

Did you clean the oil flow pipe to the cam Benny? It sounds as if it's the cam followers not getting oil, no doubt I'll be corrected.

[AlBags]

No pipe.
Check plenty oil in top end when running (through open cap with lamp if poss)
Have you mixed OLD followers with another old cam? I think you have.
If it's a sharp tappety noise, it may still be a follower.
If it's a knock that's more serious.
Are you sure of the comp figs? > Did them wet or dry?

[gsivec2013]

hi benny, did you rectify this problem. ive got the same engine with the same problem. its got 5 bar oil pressure at idle. ive ran it with the rocker cover off and its got non or very little oil at the cams hence why its very rattly. have u got a fix for it. contact me at [email protected]. cheers