Technical EML after timing belt change (P0009-62/P0011-61)

[andrewpsmith]

Hi,
I have changed the timing belt on my 2017 Fiat 500 and have EML following timing belt change. I'm totally baffled as to what could be wrong and any help would be very much appreciated.

The car is 1.2 Pop (8v) 49,000mls. Owned since 2021. Following the timing belt change, I took the car for a very short drive and the EML came on. I checked the codes with MultiEcuScan and the following were present

P0009-62 - VVT (phase variator) - Signal Compare failure
P0011-61 - Phase Variator position - Signal Calculation Failure

I read that it is possible to check the timing of the car using two parameters in MultiEcuScan, so I did this. At idle the parameters read..

Cam position 0.00 deg
Desired cam position -2.00 deg.
VVT (Phase Variator) 0.00%

Before doing the job I purchased the (Laser) Timing set and used the Crankshaft Lock and Cam shaft lock from this set to secure the shafts before changing the Timing Belt. (I did make a step wrong here as I locked the shafts with the cam 180 degrees out from TDC, however I later check and was able to fit both timing tools at TDC. It was difficult to get the belt on with the locks in place as the right hand side (non tensioner side) was very tight, but it was possible.

The car sounds absolutely fine when running. I have read in some posts that a 'phonic wheel relearn' is required following a timing belt change but have read different opinions on whether this is necessary.

I counted 48 teeth on the Cam shaft sprocket and my maths tells me that if I was a tooth out, that would equate to at least 7 degrees (not the -2.00 I am seeing at idle) but maybe the cam moves a bit once the engine is running.

Any ideas much appreciated.

Andy

 

[eeeno]

Both of the error codes are related to VVT and it means that timing is over advanced (p0011). You can see that from the parameters.

You just need to do it again. Check the tensioner.

 

[andrewpsmith]

Thanks for responding.

I have no clue how I could have managed that as I had timing locks fitted. If the timing is over advanced I guess that means I had too few belt teeth down the tight side (RHS). I tried with one more belt tooth on the RHS, but it was quite slack with the locks fitted and impossible to fit the belt on the tensioner side with the extra belt tooth on the tight side. I guess I'll have to remove either the Cam lock or Crank Lock and rotate slightly to get the belt past the tensioner. Hopefully all with come back into sync when I tension correctly.

 

[eeeno]

You have to follow the procedure described on the installation instructions. Officially it says that you need to loosen the camshaft pulley bolt with camshaft locked to get the belt tightened correctly. Read about that from the guides section. Were you able to tighten the pulley at max tension and rotate engine twice before setting the tension? Or has tensioner lost its setting or has it jumped tooth?

Does the set also have a lock for the cam pulley so that it can be loosened and tightened?

I have taken this shortcut too and got no fault codes.

 

[jrkitching]

You have to follow the procedure described on the installation instructions.

I've seen more than one set of instructions!

There are other ways to do this which don't require the cam sprocket to be loosened. It's even possible to do this without any timing tools, providing you're absolutely certain the timing is correct before you start, and you mark the position of everything before loosening anything (apart from the covers, obviously).

Loosening the cam sprocket has its own risks; personally I'd not want to do this if there is any other alternative. It's very tight; some folks have incurred collateral damage just trying to undo it.

I guess I'll have to remove either the Cam lock or Crank Lock and rotate slightly to get the belt past the tensioner.

Others have reported that to get the belt to fit correctly, you either have to do this, or you have to loosen the cam sprocket.

Providing the crankshaft is positioned so that all four pistons are positioned approximately midway down the bores, you can't damage anything by rotating the camshaft with the crankshaft locked. What you don't want is to have the crankshaft rotate when a piston is near the top of its stroke; if it moves further than intended, you could make contact with a valve.

Removing the plugs makes it easier to position the crankshaft exactly where you want it, and with them out, it's easy to check the piston position with a length of dowel.

Try removing the camshaft tool and rotating the camshaft as necessary. Then tension the belt, and refit the camshaft tool as a final check.

 

[andrewpsmith]

Thanks both for your replies.

I don't have the right size drive to loosen the cam sprocket by the look of it. I have a 50 and 60 but neither fit so I guess it is 55. I'm hoping I can get away without repositioning that. As far as I know it's been on since the car was new and the car has only done 49K so hopefully it is still where it should be. There wasn't any faults on the car prior to changing the belt so fingers crossed the position is OK.

I'll go down the route of moving the pistons midway then positioning the cam. Fingers crossed that will do the trick.

 

[puntodeltathema]

Did you plug the VVT solenoid back in after putting the cam cover back....just a thought.

 

[andrewpsmith]

Hi. Thanks for the reply re the solenoid. Yes, I made sure that was plugged in properly after seeing the error at first. It seems fine and is reporting VVT angle through the software I have.

 

[andrewpsmith]

Hi,
I'm not having any luck moving the cam by a tooth. I'm unable to refit my timing tool after rotating the crank 2 turns. So I'm going to assume I had it in the right place the first time.

I have read that due to stretch in the original belt, the ECU not knowing that the belt has been changed, it necessary to do a "phonic relearn". This makes some sense as my ecu says the timing is only a couple of degrees out at idle. Just wondering if this is worth a try?

Finally, I'm struggling to find a good set of instructions for changing the timing belt. Could anyone point me at where the intructions are on this forum?

 

[Mike1alike]

Have you tensioned the belt correctly? You shoud be able to turn the belt 90 degrees on it's longer section between two points. Here's a video about it:


And if you want to move the cam one tooth, this is an easy and effective way to do it:


PS: Yes, the drive for cam screw is torx 55.

 

[andrewpsmith]

Have you tensioned the belt correctly? You shoud be able to turn the belt 90 degrees on it's longer section between two points. Here's a video about it:


And if you want to move the cam one tooth, this is an easy and effective way to do it:


PS: Yes, the drive for cam screw is torx 55.

Thanks for the heads up. I tensioned the belt correctly. The tensioner has markers on it that have to align for the belt to be correctly tensioned. I checked these multiple times after setting and rotating the crank. All looks good.

I am leaning towards VVT pulley needing to be slackened as this will likely move the VVT pulley slightly as it will evenly tension both sides of the pulley. I can imagine this causing a 2 deg shift in my case. Thanks for the info on the torx. I'll grab one tomorrow. From what I have seen that bolt looks to be really tight so no idea how I'm going to get it off but I guess thats a problem for another day!!

 

[Mike1alike]

I wouldn't get it off, considering the engine worked just fine before you replaced the timing belt.
To get it off, you need to take the cam cover off and hold the camshaft, it has a segment for that, size 24 hex.
Can't you reset the VVT (does it have that possibility)?
If you need to move the belt on the cam one tooth (or two), do it using the method from the video I've posted above. It's really easy and it works.
About the cam pulley, I just replaced it's seal on my Punto 1.2 8V, I think the pulley and camshaft on yours are the same. At mine, the pulley has a "spur" (don't know if this is exactly how it's called) on it and the camshaft has a cut wider than the pulley's spur. The correct position at mine was exactly on the middle of the cut and there is space if you position it to the extreme, to move it exactly one tooth in either direction. I have some photos of it, put them here.
So, to your problem, I'd say you can fix it way easier if you move the belt on the cam like in the video above than fiddling with how the pulley sits on the camshaft.

 

[andrewpsmith]

I wouldn't get it off, considering the engine worked just fine before you replaced the timing belt.
To get it off, you need to take the cam cover off and hold the camshaft, it has a segment for that, size 24 hex.
Can't you reset the VVT (does it have that possibility)?
If you need to move the belt on the cam one tooth (or two), do it using the method from the video I've posted above. It's really easy and it works.
About the cam pulley, I just replaced it's seal on my Punto 1.2 8V, I think the pulley and camshaft on yours are the same. At mine, the pulley has a "spur" (don't know if this is exactly how it's called) on it and the camshaft has a cut wider than the pulley's spur. The correct position at mine was exactly on the middle of the cut and there is space if you position it to the extreme, to move it exactly one tooth in either direction. I have some photos of it, put them here.
So, to your problem, I'd say you can fix it way easier if you move the belt on the cam like in the video above than fiddling with how the pulley sits on the camshaft.

Hi Mike. Thanks for the feedback. My car has a VVT sprocket on the camshaft so looks different to your pictures (2017 1.2 8v 500) . Apparently it's supposed to be loosened as part of the belt change but it's rediculously tight (200 NM I think). Apparently an alignment procedure may be required after a belt change (phonic wheel reset) which is done through MES (which I have) so I'm planning on reassembling and trying that before removing the sprocket as a last resort.

 

[Mike1alike]

A simpler way (than taking the cam cover off) to loosen that bolt: put the engine in the fith gear and have someone pressing the brakes (or just pull the hanbrake way up). Then you can loose it.

 

[andrewpsmith]

A simpler way (than taking the cam cover off) to loosen that bolt: put the engine in the fith gear and have someone pressing the brakes (or just pull the hanbrake way up). Then you can loose it.

Thanks Mike. That's an approach I never would have thought of thats for sure!!

 

[eeeno]

The right side wheel has to come off so applying brakes or keeping it on gear doesn't always prevent the engine from rotating.

Engine is not timed correctly if locking tools don't fit after tensioning the belt. That might happen when tensioner loses the setting. Did you use correct torque to the tensioner nut? It's not supposed to be very tight. Get a new lock nut to it.

Some adventurous people just set the cam in advance and let the tensioner pull it back. Making your own markings the pulley and belt might be helpful in this method. Unfortunately VVT- engines were not supposed to be rotated backwards.

You're just going to have to do it again. Good luck.

No phonic wheel relearn is needed in your case. EML should be blinking after the belt change and then you need to carry it out.

 

[andrewpsmith]

The right side wheel has to come off so applying brakes or keeping it on gear doesn't always prevent the engine from rotating.

Engine is not timed correctly if locking tools don't fit after tensioning the belt. That might happen when tensioner loses the setting. Did you use correct torque to the tensioner nut? It's not supposed to be very tight. Get a new lock nut to it.

Some adventurous people just set the cam in advance and let the tensioner pull it back. Making your own markings the pulley and belt might be helpful in this method. Unfortunately VVT- engines were not supposed to be rotated backwards.

You're just going to have to do it again. Good luck.

No phonic wheel relearn is needed in your case. EML should be blinking after the belt change and then you need to carry it out.

Thanks eeeno,
in my case I have done the whole procedure 3 times now. Every time the timing tools have fitted to the crank and cam perfectly after tensioning and the tensioner guage fits perfectly. THe only issue I have is that there an EML light on when I run the car. (P0009-62 - VVT (phase variator) - Signal Compare failure, P0011-61 - Phase Variator position - Signal Calculation Failure) and a -2.00 deg difference on the cam position parameters in MES. The car sounds fine and appeared to run fine. I could do it all again but I wouldn't know what to do differently! There only two things I believe I haven't tried now (1) releasing the VVT sprocket, and tensioning with it loose (2) a phonic wheel reset.

 

[eeeno]

https://www.carobdcode.com/p0011-fiat-intake-valve-timing-control-performance-bank-1

You also took good care to align the valve cover and the o-rings correctly because it could be related to oil circulation to the VVT solenoid. Also it could be a wiring issue.

 

[andrewpsmith]

Hi Eeeno. I was pretty careful putting all that back and connecting it properly. I get timing angle parameters in MES. It not very clear in the picture, but the car is at idle. The green line bouncing around 2.00 (desired cam position) is the measure 'Cam Position'. Engine revs are shown in blue at the top. The car is generally managing to align the cam position to the desired cam position (according to the sensors at least). May be I need to put the car back together and do a trace like this until I get the EML light to see what it's doing at that point, or may be I just to a phonic wheel relearn first. I'm baffled!

 

[eeeno]

Have you tried resetting the code to see if it comes back?

Engine timing changed slightly even with the locks on so I'm just guessing it needs to be driven a bit to self-adapt. VVT hasn't activated at lower rpms so before taking it to a drive you might want to elevate rpms to over 5000 several times. If you are lucky these codes might disappear.

Of course you did align the auxiliary pulley hole correctly to the dimple on the crankshaft pulley? Obviously that isn't the issue now.

You could try with MES to force phonic wheel relearn procedure. Did you put oil into the solenoid when you put it back? I'm only speculating that if it had run dry for a bit ECU would just disable VVT and set those codes.