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2010-2012 Range Rover MkIII / L322
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Discussion Starter #1
After I changed timing chains(by myself), since then I have misfires, mostly in cylinders 2,4,6,8(8 sometimes doesn't listed in codes) and sometimes but very rare cylinder 5. I hear and can feel that engine misfiring on idle, but other than that car pulls and accelerates really good, no extra sounds or smog, fuel consumption is also good, coolant level is stable, spark plugs and ignition coils are new. So every second day I have codes for misfiring and nothing else. I completed vacuum test, leak test and compression tests - everything seems fine. I replaced all 8 injectors with brand new bosch injectors, but unfortunately the issue is still there. I gave up and diagnosed my car at local jaguar\land rover mechanic shop and their verdict is: probably timing chain is wrong, but they aren't sure and would like to put engine apart and redo timing chain job, but even after that they can't guarantee that it will fix the issue. I need second opinion, please advise what to do? I'm planning to do it again by myself, but not sure that it will help and decided to ask here first. Thank you.
 

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2010-2012 Range Rover MkIII / L322
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Are you absolutely certain that you locked all four cams in the correct position?

The tool which attaches to the rear of the head and slots into the cam cutouts to lock the camshafts in place cam be installed 180 degrees out.

It is essential to look for the reference numbers which appear to be stamped onto the camshaft's rear facing surface and have them UPPERMOST, not the numbers which appear etched into the camshaft's rear surface. These numbers are 180 apart.

Did you use new/updated timing chain tensioners, with the pins still in place until everything was installed, and guides or did you re-use the old ones?

If you installed the chains and set the timing marks using new tensioners, did you then remove the pins and have a little slack on the lower half of the left cam chain and the upper half of the right cam chain with everything initially installed?

After refitting the front cover and making a reference mark on the [reinstalled] front crank pulley and removing the crank and camshaft locking tools, did you then rotate the crank CLOCKWISE (as you face the front of the engine) TWO complete revolutions?

Upon re-installing the camshaft locking tools, did the tan/yellow marks on the chains and the timing marks on the VVT's all continue to remain aligned once your crank pulley had completed two revolutions?

Rob
 

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I will add the short bit of knowledge that I know. The cam being 180 deg out of order will cause low compression and misfires (barely running).Went through this with my 11 full size and sport. Expensive job at dealer but certainly worth it. No misfire, nothing.
 

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Discussion Starter #4
Are you absolutely certain that you locked all four cams in the correct position? The tool which attaches to the rear of the head and slots into the cam cutouts to lock the camshafts in place cam be installed 180 degrees out.
Yep, I used special tool to lock it.
It is essential to look for the reference numbers which appear to be stamped onto the camshaft's rear facing surface and have them UPPERMOST, not the numbers which appear etched into the camshaft's rear surface. These numbers are 180 apart. Did you use new/updated timing chain tensioners, with the pins still in place until everything was installed, and guides or did you re-use the old ones?
I used all new\updated tensioners.
If you installed the chains and set the timing marks using new tensioners, did you then remove the pins and have a little slack on the lower half of the left cam chain and the upper half of the right cam chain with everything initially installed?
Yep, following the Jag\LR instructions.
After refitting the front cover and making a reference mark on the [reinstalled] front crank pulley and removing the crank and camshaft locking tools, did you then rotate the crank CLOCKWISE (as you face the front of the engine) TWO complete revolutions?
yes, then I put back the cam shaft locking tools and checked that they fit perfect.
Upon re-installing the camshaft locking tools, did the tan/yellow marks on the chains and the timing marks on the VVT's all continue to remain aligned once your crank pulley had completed two revolutions?
No, I don't know how many revolutions you need to turn it to original position, but even in the original instruction this thing isn't required, I mean they don't ask to check marks after you rotated crank.
 

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Discussion Starter #5
I will add the short bit of knowledge that I know. The cam being 180 deg out of order will cause low compression and misfires (barely running).Went through this with my 11 full size and sport. Expensive job at dealer but certainly worth it. No misfire, nothing.
it is my hobby, so it is not a money question) I just would like to find the root cause, because even mechanic shop can't find it)) Now I'm in progress of collecting new ideas what else to check. My main question is: Assuming that timing is wrong, should it throw some code related to that or not? Because I have only misfires codes...
 

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It's important to rotate the crank pulley CLOCKWISE two turns after the initial install and then re-chack timing as there will have been a little slack in both chains when refitted.

Turning the crank counter-clockwise (when facing the engine) after installation can sometimes cause the timing to slightly mis-align and be "a tooth out" which may be what you have on one of the banks.

The reason to rotate twice is to allow the slight initial slack in the chains to be taken up and re-check for alignment. It's important to ensure this is done before boxing everything up.

However, if you took it apart once, you can do it again pretty quickly the second time, if necessary.

Are you sure the VVT sensor connector on the back of each head is connected and fully seated?

Did you use new injector install kits?

Rob
 

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Please report back what you find,
I had the dealer swap out the tensioners chains and guides and ever since i get a shuddering at idle,
it has never gotten worse nor has it gone away.

it runs great off idle and hauls when the pedal goes down
 

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2010-2012 Range Rover MkIII / L322
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Discussion Starter #10
It's important to rotate the crank pulley CLOCKWISE two turns after the initial install and then re-chack timing as there will have been a little slack in both chains when refitted.
I know, that is exactly what manual says, so I checked it the same way.
Turning the crank counter-clockwise (when facing the engine) after installation can sometimes cause the timing to slightly mis-align and be "a tooth out" which may be what you have on one of the banks. The reason to rotate twice is to allow the slight initial slack in the chains to be taken up and re-check for alignment. It's important to ensure this is done before boxing everything up.
Yes, I double checked it before boxing everything up
However, if you took it apart once, you can do it again pretty quickly the second time, if necessary.
You right, but I guess it is another 2 days of work)) That I tried to avoid.
Are you sure the VVT sensor connector on the back of each head is connected and fully seated?
Yep, I open live sensors data in SDD and checked camshafts angles with and without VVT connectors attached. Data is changing, checked on both banks.
Did you use new injector install kits?
Initially yes, and then I even put brand new injectors. Thank you.
 
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