355 exhaust valve not opening

355 exhaust valve not opening

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red_slr

Original Poster:

17,234 posts

189 months

Sunday 25th June 2017
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Pretty sure my valve is not opening. Is there an easy way to test it?
Also if its duff is replacement fairly easy?

132

474 posts

263 months

Sunday 25th June 2017
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It's been a long time since I had a 355, but from memory, if the valve is not opening you will not get the high pitched howl the 355 is renowned for.
You can used some steel wire and tie the valve open. Take it for a drive and if there is noticeable change in the exhaust note at high revs, your valve is not working.

Good luck

red_slr

Original Poster:

17,234 posts

189 months

Sunday 25th June 2017
quotequote all
Yep pretty sure its not opening but trying a few pulls from 2000 to about 6000 its actually hard to tell. I think its meant to open around 3000? Not sure if there are other factors too, speed etc?

It was wired open when I got the car but I got the supplying dealer to put it back to stock and the valve was defo working when it came back. I have driven it 4 times since and the first 2 times its was working but last night and the time before that I was thinking it sounded rather muted.

F1Sean

207 posts

182 months

Monday 26th June 2017
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Mine was wired open when I bought the car. Then I changed the exhaust and it was way too loud when driving in the lower rev range (leaving housing estate etc.) so I un-wired it, but to check it was working properly, I installed a GoPro in the engine bay using cable ties and took it for a blast.

Downloaded the footage and all was revealed - works perfectly!

Cerberaherts

1,651 posts

141 months

Monday 26th June 2017
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Get someone to rev it hard (once it's warm!) and look down at the arm on the vacuum solenoid, you'll see it poking through the black heat shield behind the air boxes. It should move under hard acceleration. If they fail they stay closed. Eventually it can trash the cats, so its best to get it sorted out. The capristo replacement valve is cheaper than the Ferrari unit, and if it ever fails it fails open rather than closed. As above, DO check the vacuum pipe, and also the metal section that runs along the length of the silencer and into the R/H inner wing, as they can fracture

red_slr

Original Poster:

17,234 posts

189 months

Tuesday 27th June 2017
quotequote all
fesuvious said:
It's probably just the vac pipe has come off.

Whip the air intake boxes out, undo the black exhaust cover and the valve is there for you.

Likely the rubber pipe has come off. Very very easy fix.
Cheers I did check that and it was in place. I checked visually along the hard pipe but its a bit hard to see so I will take the cover off like you suggest and have a proper look.

Will report back!

phib

4,464 posts

259 months

Tuesday 27th June 2017
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red_slr said:
Cheers I did check that and it was in place. I checked visually along the hard pipe but its a bit hard to see so I will take the cover off like you suggest and have a proper look.

Will report back!
Should be about 2,900 revs, mine is most noticeable in 3rd or 4th gear when it opens

Phib

red_slr

Original Poster:

17,234 posts

189 months

Tuesday 27th June 2017
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Cheers will have a better look tonight.

F1Sean

207 posts

182 months

Tuesday 27th June 2017
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One of the points above mentioned high revving whilst on the drive. I tried that, but nothing happened at all. I couldn't see the valve mechanism moving. So I took the vacuum pipe off and sucked it to check it worked OK (which it did).

Hence the GoPro route for me, which confirmed all was well. I read somewhere on the internet (must be true) that the car has to be moving, with a combination of speed, revs and under load (i.e accelerating) for the valve to open.

red_slr

Original Poster:

17,234 posts

189 months

Tuesday 27th June 2017
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I think you are right I think its about 50kph as its for EU noise regulations or something?

F355GTS

3,721 posts

255 months

Tuesday 27th June 2017
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Simon

Valve is operated by vacuum, basically there is a small soleniod mounted on the backside of the o/s wheel arch next to a vacuum tank, there are 2, only one is for the exhaust valve the other is for the air pump I think.

If the hose from the rail to the valve is not split then the normal failure point is the vacuum canister itself which rusts through.

The valves rarely fail but can be checked, they should have a permanent 12v with ignition on and the valve is switched by the ECU proving a ground signal to the other pin, once you've established which is the earth you can take a direct earth feed to it and you should hear it click and the valve should open assuming there is stored vacuum in the tank.

If you suspect the tank, take the feed to the tank and connect it straight to the exhaust valve solenoid, if the valve opens you'l know it's the tank/ local pipes

The signal goes through a white connector behind the panel behind the drivers seat, can't remember the pin number/ colour but orange and 27 rings a bell, check Ferrarichat for detail, if you get the wrong wire the air pump will start up smile


red_slr

Original Poster:

17,234 posts

189 months

Tuesday 27th June 2017
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Thanks I will try those things tonight. biggrin

red_slr

Original Poster:

17,234 posts

189 months

Tuesday 27th June 2017
quotequote all
Sorted!

It was the hose from the valve to the vac rail. On visual inspection it looked ok but after removing it and putting my finger on one end and sucking on the other I was getting air so on closer inspection I found a small tear at the end nearest the valve. I cut that section off as it was so close to the end that there was enough to reach the hard line and bingo!! Working again now. biggrin

Thanks all!!!

Kyodo

730 posts

124 months

Wednesday 28th June 2017
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Cool. That just saved you a couple of hundred quid of 'investigation' at a dealership!

red_slr

Original Poster:

17,234 posts

189 months

Wednesday 28th June 2017
quotequote all
Indeed!!!

Also some Google searches revealed that the valve opens at 4,000 RPM in 3rd gear and 2,800 RPM in all other gears.
There is also a suggestion it does not open below 80% throttle and that there might be differences between 2.7 and 5.2 and also manual vs F1!.
Ferrari don't do simple it seems!

phib

4,464 posts

259 months

Wednesday 28th June 2017
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red_slr said:
Indeed!!!

Also some Google searches revealed that the valve opens at 4,000 RPM in 3rd gear and 2,800 RPM in all other gears.
There is also a suggestion it does not open below 80% throttle and that there might be differences between 2.7 and 5.2 and also manual vs F1!.
Ferrari don't do simple it seems!
Mine is a 5.2 Manual, with foot to the floor in high gear going slowly you can seriously hear the difference

Phib

geopetrolhead

263 posts

97 months

Wednesday 28th June 2017
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Hi

Mine has stopped working since I had the switch put In to open and close it, couple of times it got stuck when hitting switch, I Want it opening And closing automatically, Is that possible with the switch wired up?

F355GTS

3,721 posts

255 months

Wednesday 28th June 2017
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geopetrolhead said:
Hi

Mine has stopped working since I had the switch put In to open and close it, couple of times it got stuck when hitting switch, I Want it opening And closing automatically, Is that possible with the switch wired up?
if the switch has been wired correctly it should still open at the appropriate revs

HardtopManual

2,430 posts

166 months

Thursday 29th June 2017
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Solenoids can also fail, so another thing to check.