Hi guy's, Timing belt issue? I changed the Timing belt on my 2013 fiat punto popular 1.2 8v and belt has slipped and has a permanent engine management light on, what is the best solution to rectify this problem. Piston 1 TDC and valves on piston no1 just rocking? Any help would be most welcome
General Timing belt issues
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General Timing belt issues
Others here can give more current advice, I am retired, however this is from a 2012 Cambelt Data manual if relevant to your engine number.
The bit about ECM learning may be what is needed.
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These are simple engines, it's hard to screw-up 8V FIRE timing so bad it flips the Check lamp.
Guide (plus read the Discussion tab, important): https://www.fiatforum.com/guides/1-2-8v-evo-2-engine-cam-belt-replacement.732/ !
Guide (plus read the Discussion tab, important): https://www.fiatforum.com/guides/1-2-8v-evo-2-engine-cam-belt-replacement.732/ !
Hi. it's very difficult for the belt to "slip" unless something is significantly wrong, like maybe a failed tensioning spring on the spring loaded tensioner. What is much more likely, especially as you've just done a belt on it, is that the belt has been fitted one tooth retarded and this is a much reported problem here on the forum. So I'd recommend that you first recheck the belt timing. Ok, I know that means a lot of work taking the mount and covers off again but unless you can be absolutely sure your timing is lined up correctly there's no point in mucking about with anything else. A 2013 engine will require timing tools to check this properly as it will have no timing marks due to the cam pulley being unkeyed. Did you use timing tools when you fitted the new belt? if so did you slacken the cam pulley retaining bolt? I ask because it's virtually impossible to fit the new belt with the cam locking tools in place if the cam pulley bolt is not slackened and trying to do so will almost certainly result in the timing ending up one tooth retarded. There's an excellent guide by Andy Monty in the Punto section on how to do the belt change on these later engines - follow the instructions for the VVT engine which also has an unkeyed pulley.
So, I think it likely that that's your problem, however, even with a correctly timed belt change, you can still end up with the EML lit. This can be due to the very sensitive engine ECU detecting that there's a difference in the timing it's previously been seeing between the crank sensor signals and those from the cam sensor. There are two forces acting here, one being simply that there may be a very slight difference between the old and new belts (personally I'm not a great subscriber to this view, I just don't believe there's any measurable difference as long as you buy a good quality belt from a "known name" manufacturer). More likely in my view is that there is a small difference in angular displacement between the cam pulley and camshaft after it's bolt is slackened to allow the new belt fitment and retightening. By the way, this particular "fault" is often recorded by the ECU as a timing fault so if you scan it for stored codes you may well find a misfire code/codes stored which can lead you a merry old dance trying to sort the non existent misfire when it's actually the relearn that's needed.
If you are absolutely certain your crank/cam timing is correct, but the EML/MIL or whatever you want to call it, is still lighting up - typically it won't light as soon as you first start the engine but after a short run - then it's very likely you need to perform a "Phonic Wheel Relearn" (This is what Mike is referring to in his post above. You'll need something like Multiecuscan or a dealer tool to perform this procedure.
Hope that's helpful and good luck sorting this out - do let us know how it goes won't you.
Edit & PS - Just noticed GrandePunto PL above has posted the link to Andy's helpful guide. Thanks.
If I remember correctly the timing tools lock the engine up with all 4 pistons at "half mast" - ie half way up, or down if you prefer, in the bores. - it's all irrelevant though because you need to use the locking tools which make no reference to piston position. The much earlier versions of this engine, our old 1992 Panda being one, were timed up using marks on the crank and cam pulleys and they were set up with one and 4 on TDC. You can't really do this on the later engines as the marks on the crank pulley and, more importantly, complete lack of marks on the cam pulley don't allow it.
The biggest problem for someone trying to do this without having access to the locking tools is that there's no way to check if the can sprocket is correctly timed to the camshaft. There's no key/locating dowel in either the end of the cam or it's sprocket so once the retaining bolt (very tight retaining bolt, so hold the cam itself when trying to tighten or slacken this bolt) is slackened the pulley can be spun on the end of the cam whilst the cam remains stationary. Once that bolt is slackened you're only going to get the correct timing back with the locking tools and that's where one of the problem lies because if you are very experienced and feel you can tackle this job without the timing tools (and actually it can be done by the "tippex" method but I wouldn't recommend it unless you really really know what you're doing with 4 stroke engines) then the problem becomes " I wonder if the cam/pulley relationship is correct on this engine. Did the last person in here set it up correctly before retightening that bolt"? and you can only answer that question by installing the timing tools and locking the engine in the timing position.
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Guide contains tools drawings (Discussion tab). You can print crankshaft tool and roughly set the crank, "eye ball" it. You don't need real tool.
Then you peep through camshaft sensor hole. Camshaft tool sets it at 10 degrees = by "coincidence" the part of the "reluctor" (or whatever you call that funny shape sheet of metal) should be right on the edge.
Then you peep through camshaft sensor hole. Camshaft tool sets it at 10 degrees = by "coincidence" the part of the "reluctor" (or whatever you call that funny shape sheet of metal) should be right on the edge.
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