Alfa Romeo Forum banner
1 - 20 of 64 Posts

· Registered
Joined
·
27 Posts
Discussion Starter · #1 ·
Hi guys,
Took my immaculate, perfect-running 29,000 mile 147 GTA in for a timing belt change on Monday. Its a 2004 so was overdue a belt on a time-based interval.

Belt, tensioner, pulleys changed - even got the correct cam lockers from EB Spares for the mechanic to use. Also new plugs fitted.

Got the call "your car's ready", and when I got there it was parked ticking over. As soon as I opened the door I heard it grumbling and misfiring like a pig. Tailpipes were jumping back and forth, engine jiggling violently on its mounts. Also, 'monitor control system failure' was up on the dash pod. Plugging it in revealed 'random multiple misfire' cylinders 1/3/5 (or 1,2,3 - it was all one bank anyway)

Long story short, I left and politely asked them not to phone until it was as perfect as it was when I left it.

A day later and they said the timing was out half a tooth causing the poor idle, and it was ready to collect.

Although now much better, the idle was much rougher than it was prior to the car being worked on, on the the test drive it felt down on power (and the exhaust stunk of catalytic converter).

Sensing I was getting nowhere, I paid up and said I would take it to an Alfa specialist to which they eventually agreed to subsidise.

By the time I'd got home in the car, monitor control system failure was back, the idle was still rough and was still slightly down on grunt.

The car has been at the specialist today (I will keep them anonymous for the time being - they are doing everything they can to sort it), and they confirmed the timing to be bang on, and said they wouid proceed to do a compression test, as all the coil packs and wiring seemed to be in order.

So I'm sure you can appreciate how well and truly gutted I am that my baby has been unnecessarily buggered up, for the sake of a non-critical t.belt change (the belt that came off was in as good a condition as the new one)

Any help/suggestions as to the culprit will be very much appreciated

Cheers
Ben
 

· Registered
Joined
·
26 Posts
We would go with the compression tests as it has been know for some dirt to fall on to the inlet valves and prevent them from seating, also the back bank inlet cam can be a sod to time up, Good luck
 

· Registered
Joined
·
276 Posts
I'd start with a compression test. A couple of years ago had my cambelt changed BY THE STEALERS. Went to collect my car and it was doing exactly what yours was, misfiring and crappy idle, turns out they got the timing wrong the first time and ended up bending nearly every single valve in the engine :cry:

I got it all fixed by another mechanic who I trust, all at the stealers expense :)

So start with a compression test.
 

· Registered
Joined
·
27 Posts
Discussion Starter · #7 ·
I'd start with a compression test. A couple of years ago had my cambelt changed BY THE STEALERS. Went to collect my car and it was doing exactly what yours was, misfiring and crappy idle, turns out they got the timing wrong the first time and ended up bending nearly every single valve in the engine :cry:

I got it all fixed by another mechanic who I trust, all at the stealers expense :)

So start with a compression test.
Oh dear - thats not a nice prospect (I doubt my independant mechanic would stand the cost of replacing valves).
They claimed it was only a half tooth out at most (which you would'nt think enough to cause damage), but I suppose if you had the same symptoms and it bent valves, then its entirely possible mine will be the same.

Why didnt I just leave the old belt on :cry:
 

· Registered
Joined
·
276 Posts
Well hopefully yours is not the case.

That was just the crappy luck I had with mine :(
 

· Registered
Giulia Quad, Cayman GT4, Cayenne Turbo
Joined
·
23,441 Posts
I think the timing is still out.... is your indie guy an alfa specialist?

You need to use cam locks specific to the GTA to change the timing belt. 3.0 locks will not get it spot on.

Trust me I had a GTA that had been timed wrong.
 

· Registered
Joined
·
27 Posts
Discussion Starter · #10 ·
I think the timing is still out.... is your indie guy an alfa specialist?

You need to use cam locks specific to the GTA to change the timing belt. 3.0 locks will not get it spot on.

Trust me I had a GTA that had been timed wrong.

Yeah thats still my gut feeling too. My indie who initially changed the belt is not a specialist no. But the company it is with now are.

I will phone EB Spares on Monday and see if I can clarify that it is definitely 3.2 GTA locks that were sent out.

Fingers-crossed that its that simple.....
 

· Registered
Joined
·
397 Posts
Sorry to hear about this.

I happen to have the eb spares 3.2 camlocks and they have the numbers 4891/1-4 engraved on them. I presume the 4891 is the part no so if your set has the same it should be correct.

Half a tooth out should not damage your valves. Mine were off a full tooth and valves are intact. In spite of the timing being off, my idle was pretty good, certainly no misfires! Of course the timing can be off in 2 directions, and one of them could have bigger impact on idling.

In worst case they had the timing off by way more than half a tooth the first time they fired it up damaging the valves, and then set it almost straight hoping you wouldnt notice and come back in a few weeks for a large and expensive repair :(

Let's hope for the best, damaged cables to coilpacks or similar.
 

· Registered
Joined
·
27 Posts
Discussion Starter · #12 ·
Sorry to hear about this.

I happen to have the eb spares 3.2 camlocks and they have the numbers 4891/1-4 engraved on them. I presume the 4891 is the part no so if your set has the same it should be correct.

Half a tooth out should not damage your valves. Mine were off a full tooth and valves are intact. In spite of the timing being off, my idle was pretty good, certainly no misfires! Of course the timing can be off in 2 directions, and one of them could have bigger impact on idling.

In worst case they had the timing off by way more than half a tooth the first time they fired it up damaging the valves, and then set it almost straight hoping you wouldnt notice and come back in a few weeks for a large and expensive repair :(

Let's hope for the best, damaged cables to coilpacks or similar.
Very helpful info Mathias, thankyou. I was infact wondering earlier if the locks had some sort of engraving. That can be my first thing to check on Monday.

Would I be right in thinking if it was mis-timed by being advanced, damage could occur, but if retarded there is no chance of damage? You would think though, even if the 3.0 locks have been supplied by accident, it wouldnt knock the timing out enough to cause damage?

Wishful thinking perhaps - I suppose its all speculative until I get some concrete evidence i.e. compression test results.

Typical for this to fall over the weekend - it doesnt half prey on your mind!

-Ben
 

· AO Car Of The Year Winner 2015
Joined
·
3,202 Posts
I had very similar problem about a year ago. Even though proper 3,2 camlocks were used, I didnt have DTI gauge so the proper crank position was set just by some marks on the pulley form the past. Also the cam pulleys were tightened before the cambelt tensioner was put under pressure and after releasing the camlocks the cams turned a bit under belt tension...

Just an example how main things can go wrong even if you use proper 3,2 camlocks
 

· Registered
Joined
·
890 Posts
I had the same problem with my GT a few years ago after having a new cambelt installed. Rather upsettingly got it back from the local alfa specialist indy with a rough idle and engine warning light. They actuallly tried to fob it off at first but on my second return agreed to have a look and told me the timing was out on one cam. They reset the timing and it was fine after that with no other changes.

Hope that does it for you!
 
G

·
Very helpful info Mathias, thankyou. I was infact wondering earlier if the locks had some sort of engraving. That can be my first thing to check on Monday.

Would I be right in thinking if it was mis-timed by being advanced, damage could occur, but if retarded there is no chance of damage? You would think though, even if the 3.0 locks have been supplied by accident, it wouldnt knock the timing out enough to cause damage?

Wishful thinking perhaps - I suppose its all speculative until I get some concrete evidence i.e. compression test results.

Typical for this to fall over the weekend - it doesnt half prey on your mind!

-Ben
Using 3.0 / 2.5 cam locks shouldn't put the timing out far enough to bring the MCSF light on. There use wont result in bent valves either. Where abouts in lancashire are you BTW?
 

· Registered
Joined
·
27 Posts
Discussion Starter · #20 ·
Just had word back from the specialist. The compression test came back good on all cylinders, they checked the timing with their own tools so that is spot-on, coil packs were swapped over from another vehicle and still the misfire on 1, 2 & 3 remained. All the wiring is supposed to have been checked too.

Their conclusion for the time being is that my recently fitted cone filter could be causing the problem (even though I'm very skeptical that it would cause a misfire on 1, 2 & 3 - surely it would be a random misfire on all 6??? Surely the air flow meter would compensate regardless of the filter??

Anyway I'm off to pick the car up now - at least I know I can drive it without fear of damaging it.

-Ben
 
1 - 20 of 64 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top