Misfire worse after new camshaft ??

Hi all , I've been chasing a misfire on my bkc engine golf . The cam was worn so it's been replaced with a new item together with lifters etc . Before the can was renewed vcds showed injection deviationon cylinder 4 to be 2.99 all others were close to 0. Now after the camshaft replacement vcds on idle shows all injectors at high 2 ,s 2.99 still on cyl 4 and the others not far off . What's going on any ideas ?? The car seems to pull ok no smoke as such but the idkeis terrible and shakes the whole car . Any help would be greatly appreciated .

How is the timing? Was the crank held with a crank lock and the timing pin used on the cam?

Sent from my S60 using Tapatalk

Check your connections and check the injector harness for any issues(at least for #4). If it's maxed out at 2.99, you either have a bad connection, or a bad injector.

For the other issues injector issues that changed value after the cam job, double check your work. Did you reset the injector lash, and are you sure it was set correctly?

Yes cam timing set with pins and double checked . The tortion value is at -1.0 .

Would the lash affect the deviation , they were set by tightening then backing off 180 degrees .

Just to clarify , when the injector adjustment screw is tightened , I take it you screw down past the spring resistance until you hit an actual stop ??then back off 180 . Can someone confirm if this is correct please . Cheers

Rechecked lash and set properly, replaced loom with a known good one , but car still runs rough on idle when warm . It's fine when it's cold . Feels like I have an occasional misfire under load at higher speeds in higher gears . Just a bit more info , jump in with any suggestions please .

The 180 that you mentioned is correct.

I assume you didn't remove the injectors, but if you did, it could be a bad seal or leak. Usually injection quantity deviation is caused by an issue or leak related to the injector, a bad cam, poor compression (HG leak, bent rod, shot rings, or even leaky injector seals).

You seem confident in the cam job, looks like your lash is correct, you checked the injector loom(still a chance that cylinder 4 is caused by a harness issue between the connector and ECU). Before replacing the injectors, I'd run some diesel purge to see if that helps. If that doesn't, I'd do a compression test and check to make sure your lift pump and tandem pump are working well(change the fuel filter if you haven't in a while), it wouldn't fix the one injector that looks bad or needs resealed, but could be the reason the others are bad. If that's still out of luck, I'd consider replacing the injector seals and cleaning the bores.

Oilhammer would likely have a better idea of the likely cause, he sees a lot of these machines with some incredibly high mileage.

No I haven't removed injectors . This is actually a used bkc lump put in place of an exploded bxe engine . I did notice that the injectors in this engine do not sit at perfectright angles in the block , could this have an affect on things . I have tried a quality Diesel purge and it didn't seem to make a difference .

I have four good injectors from the bxe engine that I'd thought about new o rings and fitting just to eliminate the injectors . The bxe engine ran fine on idle before it exploded .

One other wildcard , we are using the cam sprocket and timing wheel from the bxe not the bkc , the tabs look different , the bxe has a wide tab whereas the bkc has a two prong affair instead ... ?

Are there any useful vcds reading that I could look at for clues .

Thankyou for your reply .

Bodstdi said:

No I haven't removed injectors . This is actually a used bkc lump put in place of an exploded bxe engine . I did notice that the injectors in this engine do not sit at perfectright angles in the block , could this have an affect on things . I have tried a quality Diesel purge and it didn't seem to make a difference .

I have four good injectors from the bxe engine that I'd thought about new o rings and fitting just to eliminate the injectors . The bxe engine ran fine on idle before it exploded .

One other wildcard , we are using the cam sprocket and timing wheel from the bxe not the bkc , the tabs look different , the bxe has a wide tab whereas the bkc has a two prong affair instead ... ?

Are there any useful vcds reading that I could look at for clues .

Thankyou for your reply .

Click to expand...

The cam gear sounds like a likely trail...

Sent from my S60 using Tapatalk

Mozambiquer said:

The cam gear sounds like a likely trail...

Sent from my S60 using Tapatalk

Click to expand...

Got to be worth a try , I'll swap them over ?

Bodstdi said:

Got to be worth a try , I'll swap them over [emoji106]

Click to expand...

Try unplugging the cam sensor first, see if that makes a difference. That will force it to go into default and it will use only the crank position sensor to run.

Sent from my S60 using Tapatalk

And on those injectors, if you have any hesitation about them not being seated correctly, check. Injectors that aren't sealed well to the head or seated correctly will create all kinds of issues.

��I'll be opening it up again after the weekend . Thanks

Well , the saga continues. No 4 injector was the culprit . I've changed it out with a known good second hand item from the junk engine that I have replaced . The car idles well now but another issue has cropped up . I'll start a new thread to address this . Thankyou to all for advice received .