16v kr pinking

[leeroy16v 0]

hi new to the site looks great have a quick question

 

16v kr lump pinks under full load abve 4000 rpm change the usual dizzy/ecu/metering head but still the same

fuel pressure has been checked and all is timed up ok

 

any ideas

 

cheers lee

[ryan_16v 0]

Super unleaded.??

[Diamond Hell 0]

Check the timing and pull it back a touch.

 

Alternatively, get rid of the rubbish mechanical management system which is causing the problem.

[leeroy16v 0]

Check the timing and pull it back a touch.

 

Alternatively, get rid of the rubbish mechanical management system which is causing the problem.

what would u put on there instead m8

[Wullie 1]

KR engine needs 98 octane or it gets stroppy. If you're using that get the ignition timing checked

[leeroy16v 0]

cheers for the replys guys im taking to me dads place tommorow will check timing again for my self and do a compression test also goin to check fuel mixture ect

 

cheers

[mikkijayne 0]

KRs seem to be a bit random about their fuel preferences. The first one I had hated 95 and pinked like a bitch, eventually to the point where it shattered the top ring lands on all the pistons and stopped working :( The current daily however doesn't seem to care either way, and runs perfectly sweetly on 95. Pulls well, no pinking, and did 37.5mpg @75mph on the way from Hull to Exeter today.

 

They're funny buggers. K-Jet is great when it works and a complete pig when it doesn't. I have no idea why this current engine likes 95 and the old one didn't :shrug: They were both set to factory ignition timing...

[Supercharged 2]

Before changing / checking stuff don't rule out a bad tank of fuel - especially at this time of year!

 

Also could be blocked fuel filter, dying pump, dead lift pump, injector spray pattern - K Jet injectors should be changed every 60k according to Bosch / VW!

[leeroy16v 0]

will order a fuel filter asap and i can check lift pump my self but how would u check main pump fuel pressure has been checked by previous owner and was ment to be good

also is there a guide for checking the injectors

 

and my bad i put normall fuel init and previous owner has been using super so doesnt seem to matter what fuel still pinks

 

cheers for help

 

lee

[Supercharged 2]

Could maybe stick an octane booster in it and see if it makes a difference?

[leeroy16v 0]

Could maybe stick an octane booster in it and see if it makes a difference?

yer i was thinking that but then if it likes it its another cost on top of fuel lol

 

had it in garage today done compression test 2 cylinders are 200 psi and 2 are 185 psi

also turned fuel mixture up a tad as was low

 

when i took the plugs out they smelt of burning wierd a

 

also check ignition timing and was spot on

[leeroy16v 0]

just found a reciept for new lift pump and fuel pump so i can rule that out i think

 

:confused4: :confused4:

[davidwort 0]

I was reading this yesterday and thinking what causes an engine to pink, top of the list (as said) is usually too much ignition advance or too low grade fuel for the compression ratio of the engine.

Being a K-jet KR engine there is no knock sensing, and the KR engines aren't that prone to the heads coking up as they run pretty lean and hot usually,

so...

Are you sure that the ignition timing was correct? Did you take it from the flywheel or timing pulley mark, as the latter can be inaccurate if pulleys are slightly damaged.

I guess it's possible that the exhaust cam woodruff key/keyway is damaged and distorted and the same is true of the main crank timing belt pulley. Either of these would put your timing mark out. Ideally you want a dial gauge down the no. 1 cylinder to confirm TDC, but you can do this to within a tooth on the cambelt by a basic check with a wooden dowel or a bit of welding rod.

16v engines do sometimes jump a tooth on the timing belt if badly set up, either following a cambelt change or from a sha99ed/badly adjusted belt.

I'd have thought it less likely that the fuelling is the problem, but I suppose even if it's set to 1-2 % CO at idle it could still be running way too lean on the road. A rolling road session (50-70 quid for an hour) may be the most effective way of diagnosing this, but plugs should tell you most of what is going on.

You can check most of the ignition/fuelling sytem out at home with fairly basic tools, fuel delivery rate from pump, spray pattern of injectors at part an full throttle, all the mechanical engine timing and providing that all checks out then the ignition timing as you said you have done.

If it's happening on all cylinders then I'd tend to think it was ignition/engine timing related, but if it's only on one or two then it could be a mechanical issue of some kind.

If the engine has been running too lean for a long time then a hot point in the combustion chamber could have developed and be triggering the pinking, this could be a badly worn plug in which case it would be pretty obvious on inspection.

Alternatively, if the engine has been running too rich for too long (sooty/oily plugs) then carbon build up could be causing the pinking. This might also occur if the engine burns a lot of oil.

Plugs are a good indicator of what's going on in there, but if you can borrow a boroscope or have one of those mini LED lit pc cameras on a flexi rod you could look inside the chambers without taking the head off.

Other things to check are the cooling system as a problem here (blockage etc..) could cause the head to get too hot and tend to pink.

 

apologies for the rambling, hopefully there's something of use there :)

[leeroy16v 0]

cheers fella some good info in there

 

when i took plugs out to do compression test they were very dry and looked a dark grey colour but stunk of burning

 

coolant system has just been sorted all new pipes thermo stat and casing ect heater works a treat and engine seems to get up to temp ok

 

cheers lee