VR6 power issue

[Critical_Mass 10]

Yet another VR power issue.

 

Over the last few days i've noticed my VR doesnt seem as keen to get going, its almost as if its holding back. I have also noticed over the last few months that on overrun theres always a popping coming from the exhaust, which im lead to believe is unburnt fuel leaving the combustion chamber and entering the manifold where it will ignite, hence the popping. I layed next to the car today and revved the car a bit and let the revs settle, the popping IS coming from the manifold. Also if i rev the engine gradually, its almost as if there are is a double revving noises not just the one.... hard to explain so sorry that confuses you - possible slight misfire??? Could these 2 occurences be connected. Possible coil pack or cam sensor on their way out? VAG-Com isnt picking anything up from the Cam sensor, but i've also read on here that it wont necessarily show on vag com.

 

Also, another potential issue. The water temps generally sit at 90 but will occasionally rise to 100 but will go back down. The oil temperature however has been sitting around 112-114 degrees lately. But this could be the hot weather, but then i dont really notice the fans come on that often. Though when i was running the car tonight they did come on.... for about 5 seconds, then went off again :confused4:

 

Am i just being paranoid? Would it be worth changing the coilpack or cam sensor?

[Critical_Mass 10]

Just had a little check under the bonnet and found that the coolant reservoir cap was loose to say the least, a bad enough mistake on my part. This would probably explain the highish temps as the system wouldnt have pressurised.

 

Though, there is still the other possible problem i may have...

[Critical_Mass 10]

Anyone care to give some advice or opinion on any part of this?

[-Neil- 0]

i have similar running issues to yourself, would be interested if anyone can help.

[Critical_Mass 10]

Anyone willing to give any indication if theres a problem. The manifold never used to pop.

[Critical_Mass 10]

Anyone at all :?

[maff 10]

Ive had two corrado vr6's for a span of 6 years and both of them have popped on overrun from the backbox, i thought it was quite normal, certainly sounds good! I still get 39 mpg on a long steady run so i dont think mine is overfuelling.

[markrtw 0]

I had the popping when my valve guides & guide seals were very worn. When the revs die, it starts injecting fuel again from 1500 rpm to stop the engine stalling and this is when I would get the popping due to the lack of sealing and vacuum created on the over-run. A couple of weekends and a reconditioned head, some timing chains/tensioners, clutch etc later (epic 140,000 mile service :shock: ) and it's great again!

I found the popping is much more obvious with the Miltec exhaust - never noticed it with the std one.

[Critical_Mass 10]

I had the popping when my valve guides & guide seals were very worn. When the revs die, it starts injecting fuel again from 1500 rpm to stop the engine stalling and this is when I would get the popping due to the lack of sealing and vacuum created on the over-run. A couple of weekends and a reconditioned head, some timing chains/tensioners, clutch etc later (epic 140,000 mile service :shock: ) and it's great again!

I found the popping is much more obvious with the Miltec exhaust - never noticed it with the std one.

 

Well it cant be the valve seals as the reconditioned engine as done less then 10k. Its got a Supersprint exhaust and a raceland 6 branch on. You can actually hear it more coming from the manifold and not the back box.