97 F355 Spider ECU Issue/Smog Issue

I have emailed Bosch a couple times about the confusion in part numbers for F355's, and they always thanked me and said they would attempt to correct this.

Another example:

Ferrari lists the O2 pre cat sensor as part number 169953 for 1996 to 1999 F355's for North America

Ferrari also lists the O2 post cat sensor as part number 165170 for 1996 to 1999 F355's for North America

But, depending on what year you punch in with the Bosch online look up http://www.boschautoparts.com/Resources/VehiclePartFinder/ Bosch lists two different "oem" O2 sensors that come with the correct factory length cable and plug for the pre cat location.

You can get the following numbers:

Pre cat #13309 (which is for the 2.7 Motronic F355's made from late 1994 to 1995), 13819 or 15727 (the 15727 is supposed to be the "universal" replacement for the 13309) So it doesn't seem to make sense that either the 13309 or 15727 should be listed for 5.2 Motronic, it should be either the 13819 or it's "universal" equivalent, which I believe is the 15730.

Post cat #13820 or 15738 (the 15738 is "universal" equivalent to the 13820)

You might try calling Bosch customer service/tech support at 1-888-715-3616 8am to 5pm CST, to get a more definite answer

 

Pre and post cat sensors are not the same, and the difference is not only the length of the wires.
- heater resistance is not the same. Motronic may set a code if it sees a too high or too low heater resistance. Interverting the pre-cat and post-cat can lead to that but not to fry the sensors.
- On Bosch sensors the tip of pre and post cat are not the same. Post-cat sensors have only a small hole to sense the exhaust gases while the pre-cat have large slits. Pre cat sensors need to have large communication with the gas to react quickly to mixture change, that is not the case for post cat which need some filtering to assess the cat efficiency. Interverting the two types will probably lead to a poor closed loop behaviour, the pre-cat (which is supposed to be a post cat) being too lazzy (too filtered) for an efficient mixture control. Aagin I don't think it can fry the sensors, I suspect that the active part of the sensors are very similar.

So I would suggest to stay with the original Bosch sensors : 3819 for pre-cat and 3820 for post-cat

 

Thanks for clarifying Eric on the differences on the various O2 sensors, that makes complete sense. I have just called Bosch and waiting for a reply as to what is the "universal" equivalent to the Bosch 13819. That should help Tom get what he needs today.

Edit: I just confirmed with Bosch that the #15730 is the "universal" equivalent to the #13819 pre cat oem sensor. I also confirmed that the #15738 is the "universal" equivalent to the #13820 post cat oem sensor. I also discussed the confusion and errors in their look up again...he said they would review it with the manager....

 

I also confirmed the Bosch #15727 is the "universal" pre cat O2 sensor only for the 2.7 motronic (1994 to 1995) F355. He says they do list it for the 1996 to 1997 F355, but agrees, that must be in error. What happens is all the different parts houses are perpetuating that error by copying that information from Bosch and using it in their own parts look ups. I asked the tech what is going on, and he said they (Bosch) show a model change/break between 1997 and 1998. I explained that the change took place between 1995 and 1996 and to confirm it with FNA.

 

I would take them back to Kragen, since their website is all fubar-ed... Worst case you posted them on ferrariads.com...

 

I installed a 15730 for the pre-cat on my car last year. The tip configuration looked different than the oem one I removed. I questioned this with the Bosch tech, and he said they did have a number of tip designs, but that was still correct for my application, and not to worry. My car has been running great, no "check engine" lights and the dealer performed a major service on my car last winter, and ran the SD2 and checked all parameters and everything was good.

If you run all four part numbers on www.rockauto.com they have pictures of all of them, and you can see the slight differences in the tip design between the oem sensor and the "universal" sensor.

 

Have you checked the connector to the MAF? With your fancy new software, can you verify or confirm proper operation of your MAF?

Might simply be time for a new MAF. But order it by the Bosch part number. It is the same as an E34 BMW 540, so there are decent prices on them. Just make sure you get a Bosch one, as there are a lot of fakes/repros that are made in China...mostly on Ebay.

Best price I can find with a quick check is $269.95 with free shipping

http://www.importeccatalog.com/

Bosch part # 0 280 217 800

If it comes in the yellow Ferrari box it is over $800

 

It looks far better now. Congratulations !!!
At that stage have you try to clear the DTC, to reset the ECU and to relearn the idle parameters?
Your MAF value at idle, 12 g/s, is OK. What is the max MAF value you can read during a run?

 

BTW, have you been able to find a definition of what the P1691 is? I cannot find it listed anywhere in my Ferrari documents and files.

 

I have one of these you can borrow if you need to.

Jay

 

I was aware that there was some issue with the wrong O2 sensors being listed for early 5.2 cars and though I had it sorted out.

As it is I guess I'm still confused. I replaced both of my precat sensors with Bosch 15738 (universal splice) and 13819 OEM style with connector.

So is everyone in agreement that 15730 is the correct precat sensor for our cars (96 to 99)?

 

Tend to believe the Bosch/Rockauto part #s. I'm going to pick up the 15730 tonight at NAPA. Only about $10.00 higher than Rockauto. Will do some readings with both on Sunday

 

I find most of the errors in the various parts lookups, occur when you run a F355 with a year of 1996 to 1997. If you run 1998 or 1999, it is usually accurate. Not sure how this started, but they still have not cleaned it up completely. It was worse a couple years ago.