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Discussion Starter #1
Hi Everyone,
I would like to start off this discussion by saying please don’t flog this off before you have read it. Yes this is yet another variator diesel noise problem but I have replaced the variator, twice.

I bought my Alfa 147 16ts a year ago, only 40000miles on the clock. I got it at a reasonable price because of the noisy engine and the requirement of a service, but I like a challenge most of the time so I thought I would get it anyway and give it a service while replacing the noisy variator at the same time. So about a month after getting the car and allot of reading of mechanics manuals I ordered all the kit I needed to replace the variator, cam locks, variator removal tool, TDC, etc. During the service the following parts were replaced, timing belt, pulleys, tensioners, water pump, coolant, variator, fan belt. Car was running allot better after that but still noisy in the first 2500RPM. After 2500RPM then it is like a switch is flicked and the noise goes away.

So after some more reading on forums I was told that an engine flush and oil change may fix the problem, both by cleaning out the variator and cleaning out the tappets. So I put a can of Whynns engine flush into the engine, revved the car at 2500rpm for about 15 mins, engine off, drained the oil from the sump, replaced the oil filter and the sump bolt, refilled the oil with castrol magnatec part synthetic 10w40 (not cheap). Turned the car over and gave it a rev, still the same noise from the engine.

Back on the forums again. This time got told the rank sensor could be the problem. I replaced the crank and cam sensors, and reset them using fiat ecu scan. Still the same problem.

More advice from the forums, the battery, which needed to be replaced anyway because I had fitted a power hungry stereo. Same noise.

Again more advice from the forums, possible dodgy second variator, so again new timing belt and variator. No change.

Unrelated but encase anyone suggests this, I replaced the first cat after it had a hole in the flexy pipe, also replaced the manifold cover with heat wrap and I heard that the cover has a tendency to crack and rattle.

More research and have traced it down to the variator solenoid, have taken it apart and cleaned it. No joy. Replaced it with a second hand one, no joy. Tested the solenoid by putting a 12v power source though it and it worked, so the solenoid works. Checked the voltage of the cables going to the solenoid with a multi meter, getting a constant 7.5v from the cables in the lower revs and above 2500rpm which is when it should be at 12v. Further testing the theory I have tried connecting a separate 12v power source to the solenoid when the car is running, it makes the engine choke a bit while connected but if you take it for a run after then it sounds slightly quieter for a couple of hundred meters then goes back to the diesel noise. Another test I tried was to remove the power cables to the variator completely and try running the car. The car behaves the same as when the solenoid is plugged in (noisy first 2500rpm, quiet after) so it makes me think that it is the power to the variator solenoid that is causing the problem. It is supposed to kick in after 2500rpm to feed the variator oil to allow it to advance, and then that oil it stored in the variator once it goes below 2500 again to keep that noise down.

I have plugged my car into my laptop and have used fiat ecu scan to check if the “variable cam timing” is working and it says it is off. No option to turn it off or on in the software.

So questions:
1: Does anyone know what fuses control the power to the variator solenoid?
2: Does anyone know if there is anything else that could be causing the problem with the power to the variator solenoid?
3: Is there any way that I can turn the variable cam timing system on again?

Please any input would be nice, I am running out of cash and sanity.

Thank you in advance for any input.
 
L

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did you blow out the oil passage ways between the solenoid & the variator?

the noise at 2500 could be related a broken exhaust bracket

try running the engine with the AUX belt fitted, if the noise goes away then the probelm is AUX belt or tensioner related.
 

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Discussion Starter #6
Thanks for the responses guys.

The problem seems to be the opposite of the one davealfa11 suggested, the engine gets quieter after 2500rpm. The engine runs quite well in the low and high revs, it’s just noisy in the low revs. There is no miss fires of anything like that. No fault codes in the ECU.

Yes I tried blowing out the oil lines in the cam and the line under the 2nd cam lock on the inlet cam with a tin of compressed air.

It’s definitely not the exhaust bracket, have checked all of them.

I will try and get a youtube clip done tonight if possible.
 

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My alfa specialist mechanic mentioned something about the catalytic convertor being one of the main reasons for my similar complaint about diesel noise on startup. Not worth the repair cost to fix, other than the noise, it's no drama he said...... Maybe??
 

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Discussion Starter #9
Good shout, I will try running it with the aux belt off at the weekend, see if that makes a difference.

I have already replaced the first cat because the flexy pipe had a hole in it. £260 plus £15 for a fitting kit, not cheap. That was noisy with the hole in it but it’s definitely a different noise coming from the top left hand side of the engine
 

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Discussion Starter #11
Have cleaned the plunger and the hole it sits in a couple of times. Its deffinately not sticking and the spring it fine. No difference to the noise.

The cam lobes are fine, not a scuff on them. Gave them a clean with some Gunk engine degreaser the last time I replaced the variator and timing belt.

Definitely think it’s an electrical problem on the variator solenoid. Will try and get a video of the multi meter readings but might be tricky to record and take the reading at the same time.
 

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Discussion Starter #13
If I disconnected the solenoid and the noise stayed the same as when it is plugged in then it means the solenoid isn’t working when it is plugged in. The solenoid is supposed to kick in at 2500rpm to feed the variator oil, I don’t think it is doing that hence the noise.

I will try and get a video of the solenoid connected and disconnected with the engine running for comparison.
 

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If I disconnected the solenoid and the noise stayed the same as when it is plugged in then it means the solenoid isn’t working when it is plugged in. The solenoid is supposed to kick in at 2500rpm to feed the variator oil, I don’t think it is doing that hence the noise.

I will try and get a video of the solenoid connected and disconnected with the engine running for comparison.
or it is working and noise is something else:thumbs:
 
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did you buy the 1.4/1.6 cam locks or 1.8/2.o cam locks which are different. I'm starting to think that the noise you are hearing are the valves lightly touching the pistons & when the variator is activated it advances the timing which allows clearance between the psitons and the valves.
 

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Discussion Starter #18
I’m pretty sure. While the cams were locked in the right position and before I put any of the belts back on I ensured that the 1st cylinder was at TCD, I used a DTI and a TDC to check this. I can run some sort of dyno check with the fiat ecu software I have if that helps.
 

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I’m pretty sure. While the cams were locked in the right position and before I put any of the belts back on I ensured that the 1st cylinder was at TCD, I used a DTI and a TDC to check this. I can run some sort of dyno check with the fiat ecu software I have if that helps.
did you fit and then rotate then get no1 to tdc again and tried fitting cam locks agin to check?
 
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