I am interested in hearing from anyone with a 355 and Hyper-Flow cats as to whether they get CELs for the cat codes p0422 & p0432. I am having these two codes trigger a CEL and they won't stop popping up. I installed the cats with rebuilt QV London headers and a Quicksilver exhaust JUne 2009 during my 30k. I was under the impression from their website that they maintain OBDII compatibility.
Actually I just had to replace my Hyperflows during my 30K service. We put on new headers and all new exhaust ECU's but kept getting error codes. Richard then advised me that the exhaust temps were the same at both ends of the cats. The only option was to get new cats. The Hyperflow people were very fair with me but I was under the impression they had an unlimited warranty when in fact it's a five year warranty. Since putting on the new cats then we've had zero problems.
Is it possible to test and determine that they are in fact bad? I know very little about cars. Yes, I bought them from Daniel @ Ricambi.
I have them on my 97 355B with no problems at all. I've had them for over 3 years. They improve the sound if you can believe that. I have Tubi and Hyperflow cats. Great combination. Sorry, don't know if there is a way to test what you have unless it fails the Emissions testing. Your Ferrari tech can also test the exhaust temp and give you an indication. Or, you might get a CEL telling you that there is a problem. That is what I had and we found the insides of the stock cats broken up into little pieces on one side.
Interestingly enough, my left OEM cat was completely hollow when my tech took it out during my 30k last June. I never got any cat codes then! LoL! I'll ask him tomorrow if he can check the cat temps. But seriously, what is the chance that BOTH are bad?? That's my question..
When I had mine replaced one was bad and the other wasn't. However, if the one went, likely the other would sooner or later. So, one bad, one alright- replaced both. No worries.
And, by the way, if you go Hyperflow, you will like what you hear and feel. It may be in my head but I believe I got a bit of a power boost.
I think you may have misinterpreted my post. I installed Hyper-Flows back in June 2009 during my 30k. The cat that was bad was the factory left one--but I never got any CELs even though it was completely hollow with the pieces stuck in my OEM exhaust (We replaced that, too). I am doubting that BOTH Hyper-Flows went bad at the same time. And I doubt they were defective when new because I drove the car 2000 miles before I got any CELs--when I clear the codes they always come back in 150-200 miles.
Since it's now happening every 150 - 200 miles before the CEL pops back on again, how many times did you start the car after clearing the code before seeing the CEL? My understanding is is takes three starts before it will throw the code again after its been cleared. The only way to check the cats is to have a Ferrari tech hook it up to check the exhaust gas temp readings from the front and rear O2 sensors and measure the difference in temps. In my case, they were the same which threw the code. With the cats working properly, the rear temps should be higher. I would strongly recommend taking the car in and having it thoroughly checked out. It's likely the cats went bad but there is usually a contributing factor that caused it. Hyperflows are high quality and I doubt they went bad all on their own since they are less than a year old. It could be a mixture issue, etc. Net, find the cause otherwise you may have the same problem down the road.
Here's the deal. First, there is no incompatibility whatsoever between the Motronic 5.2 (OBDII) and aftermarket catalysts such as the Hyper-Flows. The Motronic 5.2 *may* throw on a Check Engine light after installation of the catalysts because it has not yet learned the new parameters that the new catalysts are providing to the Motronic. After a few start-stop cyles, the light should go away. The Motronic is able to adapt to the new parameters and accept them. What error codes are you receiving? You may have an underlying problem that has nothing to do with the catalysts. If you had a bad catalyst previously, simply slapping on a Hyper-Flow is not going to solve your problem. You must have your mechanic disconnect the oxygen sensors and perform a 4-gas analysis on the exhaust gases BEFORE the catalysts. If the numbers are out of range, your problem has nothing to do with the catalysts or the oxygen sensors. If they are normal, then the problem exists elsewhere: next have him check the oxygen sensors -- are they doing their job? How is their condition? Finally, you may want to test the exhaust gases out of the exhaust to see if the catalysts are doing their job. But the most important thing is the 4-gas test before the catalysts. If your mechanic cannot perform this test, take the car elsewhere to have it performed.
I was getting codes very often after switching my cats back 3 years ago. Had to replace a couple O2 sensors that were flawed and problem resolved. Sorry, missed the point of your previous post. I changed the sensors myself. Easy job.
I don't understand this. O2 sensors don't measure the exhaust gas temperature so they can't be "seeing" a temperature difference. Temperature measurement is the job of a thermocouple and you would need two on each cat. (before and after) to measure a difference. PERHAPS the single thermocouple is not seeing a temperature as high as expected at the output of the cat. (because it's not functioning correctly or missing) and then generating a code based on this. I don't see any temperature DIFFERENTIAL coming into play here.
^^^ correct. Primary o2's are used for closed loop fueling control. Secondary (after cat) o2's determine catalyst operation. Thermocouples are only there to warn of catalyst overtemp. I attached a screen shot of a scan I just took on a 2010 camaro. Second chart up from the bottom. Blue lines are primary o2's in closed loop. Orange lines are secondary o2's. That's what it looks like when the catalysts are working. If they are not working the secondary o2's will follow the same pattern as the primary o2's. Image Unavailable, Please Login
hmmm...... just read something interesting in Vol. 1, C16 of the workshop manual. It says the rear o2 sensors have a DOUBLE function. a - detecting aging of the catalytic converter by comparing front and rear o2 sensor signals b - it corrects the mixture in case of front o2 sensor aging Bottom line is it appears the rear sensors can, under certain conditions, operate as the main input for mixture adjustment when the Motronic 5.2 is not "happy" with the signal it's getting from the front sensor(s).
Guys, first thing is that you have to understand exactly what the rear sensors do. let's forget the "trim" function where they can supplement the front sensors to compensate for sensor aging - you really don't need to know about it right now. lets only consider the catalyst monitoring function. Understand, that ANYTHING you read in "public documentation" (Service manuals/etc) will be digested and dumbed-down and in some cases actually technically incorrect. OK. So how do the rear sensors tell the cats are there. When your car is operating in the "emissions region" the ECU is programmed to provide a stoichiometric (Lambda = 1.00) fuel mixture to the engine. The front O2 sensors get the mixture to 1.00 precisely using something called a PID or Proportional Integral Derivative control loop. Basically by swinging the mixture small amounts rich and lean of the precise sensor switch point at Lambda = 1.00 So let's make up some stuff for example - the front sensors voltage swings from 0.150v to 0.750v as the fuel mixture is "just lean of stoich" and "just rich of stoich". Your O2 sensors are actually batteries which function based upon the natural logarithm of the ratios of concentrations of OXYGEN in the exhaust gas and the ambient atmosphere. So a very small change in AFR right around lambda 1.00 cause LARGE swings in the voltage output of the sensors themselves. Because one of the main functions of a 3-way (Red-Ox) catalyst is to "store oxygen" those swings will be MUCH LESS prevalent with a correctly functioning catalyst. (Gross simplification follows) Inside the ECU code, there is a mathematical function that essentially compares the ratio of the rich-side voltages (pre and post cat) and the lean-side voltages (pre and post cat) and sums up the values for a predetermined number of cycles. It then calculates what is effectively the "average of the ratios". (End Gross simplification) This number is compared to a preset number in the calibration. If the number exceeds the preset number in the calibration, then you get a MIL (Check Engine lamp) for "Catalyst efficiency". Anyone who tells you that a "free-flow" catalyst doesn't effect this calculation is F.O.S. The calculation coefficients are experimentally determined during actual testing using the FTP-75 procedure and NEW STOCK CATALYSTS to determine the "max allowed value" which is usually set at 1.00. The only question is does it effect the value calculated ENOUGH to violate the threshold regularly and generate a MIL. The true answer is "Sometimes yes, sometimes no" - also stated as: TANSTAAFL - There ain't no such thing as a free lunch. To make a free-flow metal matrix catalyst that can ALWAYS pass this test, you have to use HUGE amounts of precious metals - amongst other techniques. (I know all of this - because it is what I do for a living) Here (from internal documentation) is how Bosch explains it: I apologize for the translation from German thru Italian to English (sort of) Blame Bosch - I didn't do it Enjoy, Jim Conforti
Good stuff Jim. Are you able to tell us why the front and rear o2 sensors on the OBD2 355 are different part numbers? Is it just something silly like different length wires? Why all the different part #'s for Bosch o2 sensors? I mean other than 2-wire, 4-wire, different connectors, cable lengths etc. are there different "nose" lengths (part that's in the exhaust stream)? Different shielding on the noses? More powerful and less powerful heating elements?
Yes, there are different shields, different connectors, different wire lengths, etc - that will all give a Nerst sensor a different Bosch P/N. They all function the same though. Physical Chemistry is a wonderful thing - but don't tell my old PChem prof. I said that Edit: An example would be on a BMW M5 (E39) the Plastic on the pre-cat sensors is MALE and the Plastic on the post-cat sensors is FEMALE (different part #'s) this is to prevent someone from messing up pre/post connections at the ECU.
How do you feel about substituting a "universal" Bosch o2 sensor for a much more expensive one that came with with the car? Major bad idea? Hit or miss? Decent chance it will work okay? Do you know of any chart or matrix that shows superseded Bosch o2 sensor part numbers or "equivalents?" The reversed connectors on the BMW makes sense (no wonder then that Ferrari didn't do that... at least on the 355).
