P0152-front O2 sensor hi voltage. READY TO GIVE UP.

Hey Matt, what was the cause of your repeating PO152 code?

 

Hi @RedNeck , did you manage to sort out your O2 sensors issues? I have kind of the same issue with front O2 sensor at 1.48V and throwing fault code for High o2 voltage (and back O2 sensor voltage at 0.16V).

 

Thanks, I get my 4 roll-over valves on order so hopefully will sort the issue.

 

Please post the update whether or not your roll-over valves fixed the issue.

 

Hi there, managed to replace the four roll-over valve (although I broke one of the new one when tightening it => Use a plier to screw it in by holding the central part, do not only use your hand and use the connection to the tube as a lever as it worked fine for the first 3 valves but not for the 4th one as this snapped on me and now need to buy a new part and re-lift the roof).

Unfortunately it did not change much:
- it seems 2 out of 4 roll over valves had been replaced already as 2 of them had the black seal but 2 already had the green rubber seal.
- No Evap leak detected on scan tool BUT
- still smells a bit of fuel when I drive
- no misfire detected but Engine does not seem to run as smoothly as when I bought the car / before the timing belt were replaced
- the Cat are still slightly red (very little though, you need to look very carefully) at the screwing site of the rear O2 sensors after 15km of driving including 8000 rpm at the end of the drive (on both sides) 9maybe less red than expected because I drove the car without the engine bonnet on... not sure that would change anything though).
- O2 sensors value still weird with rear O2 sensors voltage oscillating between 1.5V and 5V (whereas meant to be between 0.25V and 0.65V according to workshop manual.

I did an EVAP smoke detection test by inserting the smoke via the fuel trap. Did not see any smoke coming from any EVAP line BUT the seal with the Fuel filler was not 100% tight =? Where would you introduce the smoke hose on a 360 to do a proper EVAP leak detection?

Also, could my weird Rear O2 sensor values be due to some ECU adaptation that corrects the value? I understand from the Workshop Manual that it is necessary to initiate a "Self Learning Cycle", HOWEVER, it also says "The Motroniuc ME 7.3 ECU does NOT allow the user to delete the parameters set during the self learning cycle or to readjust them, by cutting off the power supply to the ECU. A testing step has been added to this phase, which makes it possible to reset the ECU. To ensure the engine functions properly, it is necessary therefore to delete the paraneters set during the self learning cycle, each time the actuators are replaced" => What does all this mess means? I thought that by disconnecting the ECU, these self learnt parameters were being deleted. Isn't is that the case?

I also noticed that the kind of canister to which the EVAP Roll-Over valves are connected, has a blue hose (on both sides) that clearly does not look OEM. Is that normal? (the pictures with the green valves below)

Tip of the day to lift the roof alone
By the way, for those who lift their roofs by themselves like I did yesterday (and sorry as this is really an obvious trick... but clearly I did not have it before LOL), I found that introducing threaded rods on both sides before lifting the roof was very useful to keep the rook well aligned and not risking the angular feet of hitting anything (like leather etc), and also helps guide the pillars straight into place when you put the roof back down.
Be careful though as the thread pitch are not the standard 1.5 or 1.25 (forgot which thread I used), so the rod will only go in for a few mm (as you do not want to force and mess up the thread, so be careful when you thread it in). I may buy a threaded rod with the correct thread pitch though

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Hi folks, quick update on my end.

The fuel smell remained the same despite replacing all EVAP and having replaced the fuel pumps (preventively).

Did a smoke test on the engine system and no leak whatsoever.
Did a fuel pump actuation test and no fuel leak on either side.

Turns out I think the fuel smell on the right side was mostly (if not exclusively) due to the ring being slightly loose, so pressed very hard on the fuel pump and tightened the ring more tightly and made sure there was no vertical play whatsoever on both side and noticed a very strong improvement with almost total disappearance of the fuel smell.

Maybe the remaining fuel smell is due to the remaining fuel traces where the pump seats, or maybe another minor source.

That said, despite no misfire anymore, no evap warning, no dash lights, no fuel smell, my o2 sensors (both sides) are still a tiny bit red at the thread level and I cannot explain why.

Also noticed that my f1 gear oil is leaking slightly as the hose seems to have aged, but looked at the price and by principle refuse to pay USD 200 for a 10cm hose that costs Ferrari USD 5 to manufacture so if you know the internal and external diameter of part 179338, please let me know as planning to make it myself

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My Issue continue with small improvements every time I change something.

Yesterday I tested by Rear O2 sensors and looks like they work OK (unless you tell me otherwise based on the pictures) as I tested them reaching 0.95V when heated very hot with a lighter, and the resistance to measure the heating elements are at c. 13 Ohms.

Since the sensors read fine, I am not too sure how my diagnostic tool tells me that my Rear O2 sensors fluctuate to up to 5 volts :-(

So looks like my issue of very slightly glowing red around the rear O2 sensors come from my rear O2 sensors.


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Gvan ...

I am not sure if the heat-the-O2-sensor thing is a valid test of the O2 sensor functionality.

 

Hi @yelcab , the test was only to see whether the sensor provided values between 0.1 and 1V, which it does. So indeed it is not really a valid test to see if the value is correct, but a valid test to demonstrate that the sensor is not fried and provides values to the ECU. It also proves that my OBD 2 reader saying that the rear lambda has a reading of 4.5V from time to time (and I have read the same from other people) is just not right.

However, the more I look into this, the more I think that my Right MAF might be faulty.
Talking of MAF, looks like Bosch upgraded the MAF and that we now should use BOSCH reference "028021808M" rather than the original "0280218012"

G

 

I see that Bosch 028021808M on Amazon goes for $65. Surely, that is fake Bosch, is it not?

 

I am not sure if the one on amazon is fake but if you are refering to "https://www.amazon.com/0280218190-0280218191-0280218173-A2730940548-LIUMO-AUTO/dp/B0BFQ6KHD7/ref=sr_1_1?crid=2ZRZC8CPFKKPX&dib=eyJ2IjoiMSJ9.KhJz44sy8pmWKW9IfR62xg.hUSydmsM-GAY7s4_d17ipjUWOzsEzrMjs64Dg75XraM&dib_tag=se&keywords=028021808m&qid=1731950432&sprefix=%2Caps%2C126&sr=8-1" then it clearly states that it is from a Brand called LIUMO-AUTO so is NOT a BOSCH part

The Bosch official Website (https://www.boschaftermarket.com/gb/en/parts/-/Details_of_Air_Mass_Meter_for_vehicle_Ferrari_360_Spider_2000_-_2005_294kW_F131B/pi/categories/,Electric_Parts,Fuel_Supply,Gasoline_Parts/products/028021808M/vi/vehicle/SR4JMI8/) states that the 028021808M is the reference needed on 360s (they also have the part ending 012 on their website).

When you look at the reference, it is a 7th Generation MAF where a 5th Generation MAF was initially installed on our cars (the part ending "012"). I don't think it makes much difference (except I hope a more stable voltage etc), but note that the "08M" version is cheaper on quite a few websites, including that website : https://cars245.com/en/item/bosch-028021808M-mass-air-flow-sensor/ from where I bought my Fuel pumps last year and were absolutely legit Bosch Fuel Pumps => so I think/assume the MAF on that website should also be legit MAF.

G

 

I will second the vote that the O2 test is not valid. They have a heater circuit in them but that just gets them up to temp quicker and if faulty usually throws a heater circuit code. The sensor itself measures oxygen. Its only job is to determine if the cat is functioning or not. The front O2 changes the engine parameters but the rear has no affect on drivability. Now a faulty front O2 can send incorrect readings to the ECU causing it to dump fuel and run rich which will overload the cat and throw a rear O2 code. Seeing as yours are flowing red that could be an issue but I have never looked at mine in the dark to see if they glow or not.