So it seems my first emissions test has failed because of CO. Limit was 1.10 and test value obtained was 2.41. This is a 95 F355 and there are no check engine lights. There are the intermittent SLOW 1/4 and SLOW 5/8 lights however and a rattle in the (stock) exhaust in a narrow range around 3k RPM. I couldn't eliminate the rattle so it's internal to the exhaust. Bad cat? Does anybody know what I should do first before taking it to a specialist? I figure if there are no check engine lights then there's no problem with the O2 sensors.
Are you sure that someone hasn't removed the bulbs from the check engine lights in the dash . Seriously, is the check engine light self-test working OK? 2.41% CO is high for a modern injected car even with no cats. What version 355?
If I were you, my first course of action would be to consult Dave Helms at Scuderia Rampante. I would hardly venture a guess without seeing your car - and Dave knows a whole lot more than I do, anyway. I solved my own emission failure problem by having Dave put in Hyper-Flow cats - and I absolutely love them! Great sound, better performance, greatly reduced likelihood of fire and I barely registered in any category when I had the emissions re-checked here in Colorado. I don't work for Dave or get a kickback from him. I have no association with Hyper-Flow, either. Just that Dave is, IMO, the best Ferrari mechanic available, and I know that Hyper-Flows work great.
Check your cats!!! I had the same issue with my 93. Ended up being the cats. Hyperflow is the ticket. Good luck.
There's always a Check Engine Code associated with a SLOW DOWN LIGHT illumination. Now, whether that code is lighting up your CEL on your dash is another matter, but at least one code will be in your engine computer(s). So pull your engine codes (for a 1995, push the red button near each ECU, for other year 355's you'll need an ODB2 scanner).
When I bough my 355 I had some similar issues. The rattle in the muffler was the cat that blew out and the metal was rattling in the muffler. After some time it blew out. I had Dave Helms put in the free flow cats that fixed that issue. From what the dealer tells me the cats all will blow out if the are stock cats so might as well just go the high flow and never deal with it again. I agree also, the high flow cats made the whole engine bay much cooler which is good for everything. My car still passed emmisions in CO with bad cats, bad plugs, and never had a 15/30k done with 13k miles on it. So, the damn engines are built good and will pass with most of the equipment broken from my experiences. With everything working the E test was a joke. Hope that helps.
1995 F355 Spider. 100% stock as far as I know. Check engine light self-test is working so yes the bulbs are present and functional. ... The SLOW lights are a different story. I had to find replacements for them. Thank you for sharing your experience. This was my theory as well - that or a loose baffle in the muffler. It doesn't seem like it will launch out of the tail pipe anytime soon, however. I've been ripping under bridges and overpasses ever since I got my car to hear that glorious F1 sound and the rattle remains at 3k or there-about. It's true what this guy says at http://www.nsxfiles.com/f355_update.htm; "Whoever is the "sound" engineer at Ferrari that tunes the exhaust/headers should get a huge contract like Michael Schumacher, as that sound engineer makes magic happen with these cars." I wanted to address the exhaust when I perform the 30k service in a couple months (it just turned 30k last week and there are no service records at any FNA dealers that it was ever done - 13yr old timing belts?!) but it looks like replacing the cats will be relatively easy with the engine in. What about the other two cats? I guess they aren't a factor given normal test parameters for the Pennsylvania.
I tried to do this tonight, however, I don't see a red button. I see a black button as circled in red in the picture attached. Is this the right button? Regarding the yellow circle on the temp sensor wire (would these sensors also be known as a thermocouples? And if so, what type - K?). I take it these are the very sensors setting off the SLOW lights? Would that be another sign the cats are hosed? http://en.wikipedia.org/wiki/Thermocouple#K Once I obtain the codes, where do I look the codes up for the english interpretation? Image Unavailable, Please Login
I am 99% certain it's your CATs. I have the same year as yours & I failed. I took off the CATS & the element was the size of a cigar! You can get some Hyper Flows from Ricambi. Thats the way i would go. Good Luck!
Thanks everyone. I concluded it was the cats too. Regarding this red button for each ECU, where is it? I see a black button but don't want to press it unless I know what it does. Panic button?
+1 I also think the problem is most probably your cats. . . but see if Dave Helms is available to check it out. If you do need new cats, I also recommend them - as I said above. You can get them through Dave, which MIGHT actually cost less than going through another source.
+1 I also think the problem is most probably your cats. . . but see if Dave Helms is available to check it out. If you do need new cats, I also recommend them [edit: Hyper Flow] - as I said above. You can get them through Dave/Scuderia Rampante, which MIGHT actually cost less than going through another source.
The problem with the cats is Ansa did a crappy job of securing the ceramic cores within the stainless steel housings...so they eventually come loose, roll and rattle around and start to crumble and break apart. One less expensive option is to send them to Miller Catalyzer. They will cut the housings open, remove what is left of the cores and install new ones, properly secured. According to Rifledriver (brian crall) he has had good luck with them, and yet to have one fail. About $600 to $650 per side. http://www.millercat.com/ Just another option. The Hyperflows are very nice.
I have a similar issue that started recently (95 w/ 18k). I get a loud rattle sound between 2500-3000 RPM (sometimes lingers a bit up to 3500). It happens accelerating or decelerating. I assumed it was the exhaust valve. I wired the valve open and even disconnected the vacuum tube, still there. Am I really in for new cats? Is that the same symptom everyone else had?
Hey guys, Does anyone know if having the valve wired open affects the CO2 emissions? In other words, are the CO2 readings worse with the valve wired open than they would be with the valve close? Thanks! Martin
CO2 is a product of combustion. Sp it's unclear what you mean by worse. Ideally, when you burn a hydro carbon the products of combustion are CO2 and H2O. Everything else is the result of incomplete combustion and/or improper mixture.
For some context, 3 years ago I had technical control on the car and it passed emissions. At that time I had the valve closed as it is originally from the factory. Today I had another technical control and I left the valve wired open thinking that it would not make a difference to the emissions numbers. I've attached the readings form 3 years ago (top) and today (bottom). The car is due for a service but I wonder if the delta in emissions is mainly due to the test being done with valve closed before and then open today. Do you think I can just close the valve and the CO values will go back to acceptable range? Image Unavailable, Please Login
With the valve open, very little of your exhaust will be going through the main catalysts, so I could see where this would effect the tail pipe readings. My Ferrari dealer tried a valve switch on my 5.2 Motronic F355 spider and found after a time, the short and long term fuel trim settings were becoming way off with the bypass valve always open. (probably not enough exhaust was passing over the pre catalyst O2 sensors) They surmised the solution would be to move the pre catalyst O2 sensors to the main collector on the exhaust manifolds. I elected to just not go with the switch, and returned it to normal operation.
at the engine speed and load they do emission testing it is unlikely that the cats in the bypass pipe have reached operating temperature (“lit off” in the jargon). Even if the engine is hot. If the cats aren’t hot enough they don’t work and the exhaust gas reaches the outlets practically untreated. You also have the problem that the lambda sensor is not able to measure reliably (as mentioned in another post here) and fuelling will be directly affected — hence you can fail the emission test with a wired open valve. For emission testing it’s better to keep the valve closed. A friend of mine blocks the hose to the bypass valve during inspection because around these parts, in addition to emissions they also measure exhaust loudness in with a sound pressure meter!!
Having the valve wired open will affect your emission. If you leave it closed, it will come back to normal, providing nothing else is bad.
Wow where are you that they check noise levels I’m in westchester ny and most of my cars have load aftermarket exhaust and no one at the testing stations ever said anything about it but on the flip side I have had a few police officers tell me to take easy with revving Or get a ticket lol “ this after a big burn out “ Running in bypass will dramatically change your fuel trims do to the lambda (aka o2 sensor) is not seeing the exhaust flow and will adjust for a lean condition raising your emissions readings having a switch installed and moving the o2 sensor in to the manifolds before the bypass valve will keep the ECU in the right fuel mapping for emissions leaving the o2 sensor out of the exhaust flow will make the car run a little richer which means more power and the engine will run colder so if you are driving in the city on a hot summer day your temp gauge a little on the high side —- will not have you squeezing the steering wheel hoping traffic opens up so you can get air flow over the radiator lol either way you still need to replace your cats it’s up to you to have them reman or get new high flow (my choice) Let us after Sent from my iPhone using FerrariChat.com mobile app
I’m currently living in Switzerland, and they take the bi-annual safety inspection extremely seriously. This is the 4th country where I’ve registered the 355 and by far the strictest and most attentive to compliance. The traffic police also have portable sound pressure meters and regularly set up “noise traps” as well as the traditional “speed traps” so even if you go for the inspection with a standard muffler and later fit your Tubi they can still get you. It’s a strict regime. Predictably, my experience has been that the most “pragmatic” country was Italy.
Dave Helms now owns the HyperFlow name. Ricambi America lists them as no longer available. At last check, Dave will not re-core them himself (EPA smart man), but will send them to Troy, the original HyperFlow owner in Atlanta. Troy re-cored mine, wonderful job, also about $600.00 each. Those coupled with the SRI gold connector kit took care of my persistent CEL’s. I also replaced my catalyst control modules to solve my false slow down warnings. I used aftermarket CCU’s available from http://technistrada.com.
Many thanks for your input, guys! I un-wired the valve back to stock and it passed emissions no prob. However, when driving around I noticed that the valve never opens in 'stock' mode. Looking under the hood I noticed that there is no hose connected to the silver round thing. I can't remember if I took it off when I wired it open but I can't find the hose anywhere. On that note, what is the hose that normally connects to the silver round thing supposed to be connected to? Is it the spot that's circled in red in the attached photo? It seems like there is a very short rubber hose attached there now...not sure how it got like that tho...I'm hoping the dealer didn't cut it and do that at one of the services... Any ideas? Image Unavailable, Please Login
