430 Exhaust Valves... Disconnected, now a prob

This can cause engine damage. Search Technical.

 

See post 27:

http://www.ferrarichat.com/forum/showthread.php?t=8543&page=2&highlight=muffler+valve

The Poster is a serious Ferrari Technician.

The check engine light came on because you have raised your exhaust temp. which can cook your CATS and other engine parts.

To do this properly requires engineering, heat shielding and more under hood cooling.

 

Generally a check engine light is telling you something. It may only be a loose gas cap and it may be a fault but in this case I think it's telling you you're getting the Cats too hot.

A good tech and a service computer will tell you for sure.

 

I'm sorry, but Post #27 is retarded and unfactual. I seriously doubt that poster is a Ferrari Technician. Your assertation that open bypass valves increases temps is also incorrect. Have you even examined how the bypass system works on a Ferrari? Like actually installing an exhaust yourself?

The reason that the CEL comes on, at least on my 355, is because there is a temperature probe behind the bypass which is detecting hot exhaust gas when the valve should normally be shut. The CEL is coming on because your car thinks the bypass valve is not working, not because temps are too high.

Pull the CEL code, i bet it's a P1448 (at least that's the code for bypass on my 355).

 

You can doubt away but He is a Ferrari Tech at a major dealership and unlike you has the latest factory certifications.

As for me yes I have. I have also had Pininfarina engineer an "off road" shunt for P 4/5's exhaust that addresses these issues. The proof is in the pudding. The system that they engineered throws no codes.

 

The ferrari dealership disconnected mine and four of my friends 430's with no problems. I doubt seriously that the dealership would do this to cars under warranty if it was a problem. Call the dealership and ask. They plug the vacuum lines with screws. Did you do this?

 

Great point! Unless you capped the vacuum lines you will have a vacuum leak which can cause a CEL.

 

Yep, that's what they did on my 360 as well. Ferrari dealership as well.

 

I don't need factory certifications, just my intelligent brain. This "Ferrari Tech" said in your referenced post that by disconnecting the valves you are keeping them shut. This is infact opposite of the truth; you are actually keeing them open. This alone is enough for me to discredit his technical abilities.

 

Post #27 refers to having the valves closed at all the RPM ranges (the opposite of what the F430 does with the vacuum lines disconnected).

There are two types of systems, the ones that need vacuum to keep the valves closed, and the ones that need vacuum to keep the valves open.

The F430 needs vacuum to keep the valves closed, so disconnecting the vacuum line causes the muffler to be bypassed (and it gets loud, and more powerful down low). This actually helps release exhaust gases easier and the engine compartment runs cooler.

Now, with the valves closed at all times (requires a modification on the vacuum controller), yes the exhaust will run very hot and the engine won't be able to properly release the exhaust gases, causing overheating on the mufflers, cats, headers, possible damage to the engine heads. The stock mufflers are very restrictive, so shutting the valves permanently closed would likely cause damage. This is the same problem with SCCA racers installing supertrapps with multiple discs to pass sound at certain racetrack, and then blowing head gaskets, burning valves, etc.

However, a free flow aftermarket system is designed to have low restriction flow, so that's why some systems don't use valve control. In this case one needs to trust the exhaust manufacturer, because they could make a product that is still restrictive and at high RPM the engine heads/headers/cats/exhaust would overheat.

That's why I have such a hard time choosing an exhaust for my cars, when the car comes equipped from the factory with a valve control system (Ferrari/Porsche).

The F430 is designed to bypass the muffler at WOT or high RPM, essentially there is no muffler at play, just headers and cats.

Disconnecting the valves in the F430 helps the car run cooler, but there is too much drone a low RPM.

I have had 6 different CEL in my 09 Scuderia, and the car is bone stock except suspension. Curiously, when I disconnected the vacuum lines, no CEL at all for the miles I drove like that, I just didn't like the sound quality at low RPM (and I don't like it at high RPM either, matter of taste).

To the OP, disconnect your battery for 2 minutes (via cutoff switch), connect it back. Drive the car, if the CEL comes back get it checked at AutoZone (unless you have a ODB2 reader).

 

Did you plug the vacuum lines? You might find some small screws to plug the end of the rubber hoses will get the CEL to go away. If it persists, then you should re-connect.

I am not sure about if running with the exhaust vlave open increases the risks of damage on a 430. You can run some quick tests with a digital temperature meter in both conditions with the exhaust plugged and un-plugged.

I ran my 360 CS sport exhaust for a year with the valves unplugged. No CEL. I reconnected it later because I thought it was too loud when at idle and the mechanic foreman told me that I was losing a little bit of torque at the low end. I thought my engine bay was actually cooler unplugged.

Obviously you don't want to do something that will cause damage.

 

I seriously doubt also that this poster is a Ferrari Technician. Doesn't make sense. Disconnecting the valves will have exactly the opposite effect and avoid over heating the engine bay. Just try it out in a hot summer and mesure the temperature in the engine bay with the bypass plugged and unplugged. The difference is huge and it make sense because unplugged, exhaust gaz take a more direct route without having to go through the mufflet which is a terrific engine bay heater. Mine are unplugged since always and I never ever had an issue. Many other did the same and never had any issue neither. The result is lower engine bay temp, cooler airboxes and no more rupture in torque and power when revving from low to above the 3200 rpm level.

Don't unplug the power of the vacuum solenoid because this will trigger a CEL for sure (P1448 is nothing to do with engine damage or engine overheating, just a warning the current is no more consumed by the vacuum solenoid). Just remove the vacuum hoses from the bypass valves and block them with a screw or something equivalent.

oups, just saw the F430GT's very good post which is stating exactly the same

 

Ps: mroberts, please read the new thread which explains also very well the myth of engine backpressure...this explains everything

http://www.ferrarichat.com/forum/showthread.php?t=280095

 

Post 27 clearly refers to a 360 not a 430 but the op in this thread did something to his 430 that threw a code. As I said it's possible to do this in a way that won't damage the engine and the code may be a false but I still think he should hook it up to a reader and see what the code is. If it's a code that indicates too much heat in the cats which as you point out can cause engine damage I would have a Ferrari Tech who knows what he's doing make this modification rather than DIY. Personally I'm not a fan of battery clearing engine check lights without knowing what code caused them. You say disconnecting your vacuum lines didn't throw a code. Whatever he did, did. His code could be anything, it's possible that it's not related to what he did and is related to something he should deal with.

 

Not Post 7 therein.

 

You have a vacuum leak. That could be the cause of the CEL.

If you are a cheapskate like me, and want to save paying a shop...try again - disconnect the hoses, plug them, reset the CEL and you are probably all set.

BTW, the 360 and 430 exhaust valves work the same way. Disconecting the vacuum hose leaves the valve open. F430GT's post explains it all.

 

Key point, when I disconnected my vacuum hoses, I plugged them with a bolt and plastic washer, and zip tied them to a line of wires nearby.

In my 04 GT3 I ran cat bypass pipes for a while (eco-friendly F-chat guys no need to reply, you should not be driving a 2mpg car). This threw a CEL (obviously). I removed the O2 sensors from the cat bypass pipe, placed a bolt and washer on that hole, and left the O@ sensor breathing fresh air from underneath the car, problem solved.

If the post-car O2 sensor are still reading not so clean exhaust gases due to the higher velocity on the exhaust bypassed at low RPM, this could trigger a cat malfunction. Anyway, get a pyrometer a check cat temperature with the valves connected and disconnected, you will notice cooler temperatures with the valves disconnected, but the cat won't be as efficient.

 

I pulled my hoses and plugged them with gold tees! Works great and I've never thrown a CEL.

I did miss the bottom-end performance, so eventually reconnected the hoses.