Technical Random limp mode after belt/pump change

[phyconia]

As the title states I'm getting random limp mode it happened 3 times after I had the belt and pump changed. Mechanic stated that they performed a phonic wheel relearn. But I'm lost I connected a obd2 tool to see if there are any codes. The only thing i saw is that longft1 was at -35% is it normal but nothing else.

Does anyone know what it could be ?

 

[steveras57]

Get whoever changed the cam belt to re-check there work limp, mode and loss of power over 3 thousand rpm ,often means the timing is at least one tooth out!.

 

[John202020]

This is why our15 year old car is going to Fiat for the change

 

[varesecrazy]

As the title states I'm getting random limp mode it happened 3 times after I had the belt and pump changed

See posts by @AppleFarmer

The only thing i saw is that longft1 was at -35% is it normal but nothing else.

Does anyone know what it could be ?

What was - 35..?

 

[phyconia]

See posts by @AppleFarmer

What was - 35..?

Longterm fuel trim was -30%

 

[puntodeltathema]

One (or more) of three things - timing out of tolerance (the engine management is very sensitive to this), phonic learn not done correctly, or O-rings between head and cam cover not replaced (if the cam cover was off). If the cam cover wasn't removed to use the proper locking tools then it is easy to get the timing one tooth out as others have said.

 

[vexorg]

I'd be very surprised if the timing belt was out at all, anyone that does a timing belt would know how critical that is. Plus you check and recheck.
Far more likely to be the ecu nonsense that some seem to suffer. Something to do with slackening the cam bolt, but it's a low power 1.2 8v engine, why any of it needs to be that sensitive is beyond me - and someone from fiat needs a good slap for the design.

 

[jrkitching]

I'd be very surprised if the timing belt was out at all

I wouldn't. Running issues after cambelt changes are reported almost every day now, and the cause is almost always down to the procedure not being carried out correctly.

anyone that does a timing belt would know how critical that is. Plus you check and recheck

You'd think so, but judging by the number of posts we get about this problem, that's not what's happening in the real world.

The problem is that most independent garages think it's just a belt change, so should be straightforward. It isn't, and if you just do what you'd normally do on most cars, you'll likely go wrong and get into difficulties.

Far more likely to be the ecu nonsense that some seem to suffer

Highly unlikely, If it was running properly before the belt change and it isn't now, it's almost certainly because the belt change wasn't done correctly.

and someone from fiat needs a good slap for the design.

Absolutely, 100% spot on. The number of times we've seen this happen now is beyond ridiculous.

but it's a low power 1.2 8v engine, why any of it needs to be that sensitive is beyond me

I'd agree. Putting VVT onto the 1.2 FIRE was, in my opinion, a big mistake, and spoiled what was previously an excellent and reliable engine. My non-VVT Euro 4 1.2 Panda drives better than any 1.2 500.

 

[vexorg]

I'm not so sure, if you lock the crack and cam then change The belt it does just work, I've done it, jock's done it.

The error can only be electrical due to the cam position being changed.

 

[jrkitching]

The error can only be electrical due to the cam position being changed.

I disagree, it's most likely mechanical, due to the belt not being in the same place as it was before. The relative position of the cam and crank must have changed. If it hadn't changed, you wouldn't get any errors.

If the alignment between the camshaft and crankshaft were exactly the same after the belt change as it was before, there's no way either the engine or the ecu can know the belt was changed, and it should just work without the need to run any software.

Replacing the belt without changing the relative alignment between camshaft and crankshaft is much harder than it should be, and that's what's causing all these issues.

 

[phyconia]

Another layer of craziness one thing I just noticed while I was driving round the upshift downshift indicator on the dash is acting strange I went all the way to 6k in first and didn't indicate for upshift. This is the gift that keeps on giving