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

 

[The Panda Nut]

Phonic wheel relearn is a sensible step as you seem to have done everything else. It may reset and adjust for the 2 degrees. Like the others I wouldnt undo the cam sprocket. THESE VARIATORS DO GET STICKY. Really clean it until the cleaner runs clear. Bathe it in oil before replacement. Its only there to change high revs performance should not trigger anything at low revs. If they stick Ive never had eml come on just poor performance. Belt tension is important but I cant see 2 degrees change in cam could result from tension with a new belt. Phonic relearn will allow the ecu to accept minor variations between belts and may well do the trick. Its repeatable so Whats to loose.