Hi I just got my "new" car delivered. It is a really nice car and I am very happy and about to get familiar with it. The check engine lamp is on. As i can tell from the workshop manual this means on Euro cars that either there is something wrong with the AFM or the throttle positioning sensor.. I am waiting for the parts, to replace and see what happens. either way it is down on power. Noticably. It runs out of breath above 6500-7000, about where I expected the 40 valve 8500 engine to shine. A 348 I hve been driving for the last months is quicker. I hope that it might just be the check engine lamp that initiates a conservative ignition curve in the ECU and by doing so takes away top end power for safety matters. Any thought on this? I could not find anything said about that in the manual. If it does not improve after getting rid of the "check engine" lamp I will take it to the chassis dyno and have it tested and take it from there. It has stock headers, test pipes, stock secondary cats. and capristo muffler. ( I removed the bypass valve butterfly at is did not operate. ( testet it at full throttle in different gears and novacum was delivered to it.) Since I am already at it with the writing... I am experiencing also that as the oil temp approaches 200-210 F (100C) the pressure drops from 70ish ti 40-50s... at only slightly lower oil temp it stays at 70 (5bars) The oil pressure sender has never been replaced so I will anyway replace it before I start crying, hehe. What temps and pressures do you guys experience on your 355s? My numbers are taking from "cruising" at 3000-4000 rpm different speeds, ambient temp 20 deg C. Any clues? best regards
Just to be clear... You did check for ECU fault codes with an OBD2 scanner, didn't you? If so, what were the codes? A check engine light can be caused by hundreds of different things. If you removed the butterfly on a USA/Australian bypass valve, I believe this alone would generate a check engine light. However, you have a Euro car (perhaps it's not checked). Do you have vacuum elsewhere on the car? e.g. going to the bypass valve solenoid valve? Do you have a stock bypass valve or a Capristo?
There is something wrong woth your car if you think it runs out of breath. I would like to help you but you need to fix the things that are broke. Its hard to know whats wrong if things are just bypassed or removed. Often they effect each other. Let us know the codes and start getting everything working properly.
Allright thanks. I will have it scanned for error. As mentioned the manuals says that on euro cars only the air mass meter and throttle potentiomenter are related to this light. On US is it related to lots od things. Anyway I will check it. I thought only that the SD1 scanner could read codes? OBD2 is something most workshops have I assume. Bypass valve is std. The butterfly has been out of the valve for years without any error message. I put it back in because I thought it made sense to have it. I then realized it did not get vacuum when it should hence it stayed closed. I took out the butterfly but everything else is connected. Vacuum hose that is. Not been fiddled with anything else.
Yes, all workshops will have these. Depending on the type, you can buy them for less than $100. You may need an adaptor, though, if you don't have a standard 16 pin OBD2 port. Many 355s only have a 3 pin diagnostic port. Adaptors can be bought for a few dollars or you can make one yourself. It's a great investment. Here's an adaptor I bought, but you may find one closer to Europe. https://www.ebay.com.au/i/132561893496?chn=ps I wired it up to my cigarette lighter Indeed, that's what the manual says (on page C24), but your engine may still be suffering because of all the unknown faults. An OBD2 reader will help with these. Perhaps other 355 owners from Europe can comment on this. My Australian car certainly has the same system as the USA.
I have a euro car, your car doesnt have a OBDII plug. You would have to access your engine data via the ecu's 3 pin plug behind the passenger seat. Id just take it to a dealer have them scan it find out exactly whats wrong and go from there.
Thanks for the useful info. The adapters look simple enough and fiat sounds about right Just another noob question here. In the manual they talk about the SD-1 diganostic system.. Where does the OBDII come into play and how does it relate to the SD-1? I also heared that you need very expensive SD-1 factory computers/software to diagnose these cars? I will definately invest in my own diagnose tool if it is as simple as using that adapter and run it against any OBD2 reader M
The SD1 tool allows diagnosis of all the computers on the car. The OBD2 scanners can only see the data in the engine Motronics ECU behind the passenger's seat on the 5.2 car (Left Hand Drive cars). If you are lucky, the diagnostic plug will already be hanging from the leather cover panel. I soldered the wires on the Fiat adaptor to a cigarette lighter adapter (found at electronics stores or online). After you have acquired the codes, let us know what they are. Just get the numbers (Pxxxx). Your OBD2 scanner probably won't have a Ferrari selection telling you exactly what the codes are. One code may indicate a different fault on other manufacturer's car. If you haven't already ordered both the MAF and TPS, you can probably save money by buying the OBD2 scanner (It should tell you exactly what is broken).
Allright. Then I am much wiser thanks to a good friend. At least more data for those of you that a more skilled with these cars. We did not manage to establish contact with OBD connector. tried 3 different readers. and also checked the the pins where going to the right pins on the ODB2 plug. Anyway, we found that the TPS did not recieve voltage supply, hence it is not functional. Tried to drive without the plug connected and it behaved just like before. Lack of power, and partly rough idle. two more things we discovered: 1. The idle regulator that sits close to the TPS made a constant humming noise when IGN ON and it was quite warm. Is this normal? The plug to this is identical to the one going to the TPS, can there be a mixe up here? I did not dear to swap them around... 2. The Air mass sensor recieves 12v should it not get 5V? And the Idle regulator had 9V does that make sense? All help is greatly appreaciated! Mats
Got it scanned. Needed to immobilize it.... Shows 2 error codes only. P0181 - fuel temp....? and more strange the P076D - shift solenoid. its a manual car. Any clues? best Mats
I Ohmed the tps connector to see what pins it went to on the 1-88pin plug motronic 5.2. The potentionmenter is number 09016 on the drawings. as far as I can tell. In the wiring diagram right and left pin where supposed to go to 43 and 51. instead they went to 69 and 16.. which according to the diagram is something very different... Either I am mixing up something or there is indisrapencies in the wiring diagram. I am at least certain that it is for the 5.2. US and Euro diagrams are similar in this area. Running out of options. Is the ECU broke and wont supply 5V to either pin 16 or 69?? I would imagine this to be very unlikely. Mats
I meant it where supposed to be 43 and 52 pin according to the documents. There is no supply voltage reaching the TPS either way.. also checked when engine was running. I found some links in here to a older thread about someone who had voltage issue at TPS but it seemed it as related to connector mixed with knock sensor.. M
As some of you perhaps was waiting for..... I swapped the knock plug and the TPS and at made sense. Now its working! It pooring down here now, will go for a test drive later. Just at idle its already better sounding and more responsive so its promising! Puh. After the service they propably did the mistake of swapping. I would assume the check engine light to disappear after a while. I disconnected the battery now, lets see Mats
Well done! Yes, those 2 plugs do get mixed up sometimes. That's why it's necessary to use the diagram. Plug colour can also be a clue. On many cars, the TPS plug is black (so I've marked the diagram accordingly). 5.2 Engine Control Hope the test drive goes well. If the check engine light doesn't disappear, you may need an OBD2 scanner to erase the fault in the ECU memory. Did you deactivate the immobiliser?
Yeah thats what I had to do to make it work... so I have no erased the fault codes, allghough there where no code for the TPS or knock. 2 codes only for fuel temp and for gear shoft solenoid... dont ask me why. Anyway I erased them. maybe after som driving the check engine light will go away.. On the live stream via OBD2 I know see that I have a working TPS, I did not have that before.. M
I can only think of two things... You either have the wrong ECU fitted, or, as I mentioned previously, most OBD2 scanners won't have a selection for F355 5.2 cars. The codes may be correct, but not the faults displayed on the scanner. Can you remember what the codes were?
I thought that might be a possibility, but I don't know why an F1 car would have a fuel temperature sensor (perhaps it doesn't). Getting back to your codes... Strange.... Those codes are not even on the Ferrari list that I have. Also, none of the codes I have show letters at the end. Your check engine light didn't go out after you erased the messages? Or didn't you start the car yet? Note that some faults only illuminate the Check Engine light after a couple of drives. However, on your Euro car, it seems that very little puts on the light anyway. It might be a good idea to run an OBD2 check from time to time to see if everything is ok. Anyway, please let us know how the test drive goes
Hi yes. Drove just about 35 kms. Not enough to get the lamp away it seems. It idled better but not faster under full load. It seems that my obd reader cant get rid of those two strange errors mentioned above. They are still there. I will try with a more pro diagnostic tool and see. From 6500 and up it feel like it lacks about 100 hp. It has peak power at 8200 ish pr the documents. Perhaps there will be a change when lamp goes.. It runs clean and sounds good, but feels like accelerator is not maxed out or ign is retarded 10 degrees. I expected a difference from the 348. I think there is something fishy somewhere. Throttle position according to the tester live stream is only 37% at max pedal. This is not driving, ign on and pushing accelerator from fully closed to fully open. Could there still be something faulty with the TPS despite it now has power at function to some degree? Any good idea how to diagnose that further? Anyone has a OBD2 tester and a 5.2 car at hand capable of hooking up and see what throttle percentage you manage to get ? Mats
Drove the car 40kms since fix in total and then the check engine lamp switched off! A dash with no lights! It still feel slow at full throttle and high rpm. I brought along the OBD2 reader to check the live data. The Throttle sensor showed 38% at full throttle. Does anyone have knowledge about this value? Seems strange to me. I am used to 95-100% for full throttle. I have checked the throttle linkage and full is full, mechanically. But If the ECU still thinks I am at 38% TPS it cant possibly be good? Even though it calculate based on Air mass. Manual says that ECU makes use of 2 positions. idle and full throttle if system is normal. It propably never gets full throttle input. Secondly the ign advance is ridicolous at way over 40 at full chat. I think I saw 44 degrees as 6000-7000ish rpm full throttle. Any input on this. I guess I am very very eager to get to know my car and learn it and also get it right and in good working order. best regards Mats
Disappointing.... The throttle reading doesn't sound normal. Accidentally putting the electrical plugs on the wrong components is not uncommon, but I haven't heard of any cases where it has caused damage to the ECU or components. Perhaps it's simply a faulty TPS. TPS faults are relatively common. Anyway, the Workshop Manual gives some resistance values for the TPS: Pins 1 to 2: constant 2,000 ohms for all throttle positions (20% tolerance) Pins 2 to 3: 850 ohms +/-18% (at minimum throttle)/ 2,700 ohms +/- 20% (at max throttle) Pins 3 to 1: 2,700 ohms +/-20% (at minimum throttle)/ 850 ohms +/- 18% (at max throttle) If it's easier for you to check these resistance values at the ECU plug, then, according to the wiring diagram, pin 1 (earth) = pin 71 on the ECU, pin 2 is pin 53, pin 3 is pin 44. The wiring between the ECU and the TPS shouldn't affect the readings too much. However, I'm not sure if these min/max values are based on pedal position or TPS position. I don't know if you have the workshop manual, but it gives a good description of the operation of the TPS. Summary: The car must be started with your foot off the accelerator pedal. The ECU records this TPS position as "idle". Maximum TPS is considered as 72 degrees above idle. The ECU only looks at minimum, mid point and maximum values unless the MAF fails. Unfortunately, that puts us back to your original situation. Both your MAF and your TPS might be faulty. Here's a forum post showing how cheap TPS replacements can be: https://www.ferrarichat.com/forum/threads/355-5-2-6spd-throttle-position-sensor.557972/#post-145515775 Note that dielectric grease should NOT be put on the pins. Note that cheap MAF replacements can cause issues (at least on F348 cars). If a TPS doesn't fix your problem, then I would find a quality replacement MAF. There may be other faulty components, but they may be still within acceptable range, so not generating codes. Sorry, I'd check my own car for you, but I don't think my OBD2 reader shows throttle position. I'll let the experts comment on your ignition advance values.
Note that this earth is not an earth on the car, but an internal earth in the ECU (Your ohmmeter probe must be put on pin 71, not on the car chassis).
I am traveling so I have no resources with me to help you. What I can say is if the mechanic made a mistake with the TPS connector and the knock sensor connector, then it is possible he made other mistakes. At this point you need to find a mechanic that is very familiar with these cars and have him go through the car, or develop this knowledge your self. I don't recognize the error code you have so no opinions there. I think you need to measure out all the signals at the ECU to figure out what is going on. From your description, another look at the TPS seems to be in order. Good luck
Guys... I have found the issue. !!! As mentioned the TPS showed 38% at full throttle. I had a positive stop at this angle. I was about to replace the TPS when I saw how little the butterfly shaft actually rotated as I moved the linkage by hand (after taking off the water reservoir tank). Then I took my inspection camera and looked down into the "trumpets" whilst moving the throttle. I realized to my great relief that at "full throttle" it was not even half open... Thats the answer for why I felt id didnt pull at higher rpms..... SO.. next, why did it stop there? After some more inspection I found that the hoseclamps that secures the tubing between throttle bodies and plenum where positioned in a way causing a positive stop for the throttle mechanism one of the sides.. Loosened, rotated, fastened and put everything back together. Finally able to get full air flow at high rpm the car is transformed. It is so much more powerful. I am so happy. Anyway thanks for the help and tips guys. I really appreciate it. I am now a very happy owner. Ther sound is just ridicolously enjoyable Mats
