Error code 66

[Problem Child]

According to NSX prime an error code 66 means: "Rear Secondary HO2S Heater Circuit Malfunction (Bank 1 Sensor 2)"

What does this mean?
How much will it cost to repair?
Must HUK do it?
Can I use the car in the meantime?

[nobby]

i think thats your O2 sensor ... they come with a heating element so its gone faulty based on my techinical understanding
what will happen is again my take on it/understanding; if heater faulty sensor will send faulty signal to ECU, she will think cat is cold therefore throw more fuel into cat to warm it up

sensors can be purchased outside of HUK, most come without the grey plug so u have to do a bit of soldering on the cheaper variants but others offer this at a price still less than HUK ... check out NTK, plenty on ebay too will depend on price point ... HUK is like over 200 quid for these. KAz sometimes has stock of these so might be worth a tinkle

check Kaz's or Sudesh's refresh page (the latter defo has info as he discusses my car)

then its gettting it fitted ... pending on how long its in there they tend to be a pain removing so some labour charge too (unless u do it urself)

car should run OK with it faulty but may not be as fuel efficient ... when my sensor was acting up, my car appeared to run OK perhaps not as lively (no proof), but on start up she was definitely running rich!

IM PREPARED TO BE FLAMED NOW if my technical assumption is completely wrong! :) (we all know about ass-u-m-ptions)

[flyingsniffer]

Geoff, I assume yours in OBD I?Mine is OBD II and I had error code P0141 which was same error. I changed the O2 sensor myself last weekend. Bank 1 is the rear of the engine, so follow your exhaust system: no 2 is the second one (derr...) at the back - actually the easiest to get to.

I got the sensor (plus one for Bank 2 sensor 2) from someone on here, or you can get them from www.sparkplugs.com,although they come with longer tails than OEM so you need to tie up some of the wiring. The biggest problem is getting the old sensor out: Kaz advised additional heat around the unit but mine came out after a good run of the engine

To make it easier if you can, remove the heat shield around the rear box. My bolts were all shagged so I stuck a spanner on the old one and eventually got enough grip to shift it. Once that's done, it's simple.

TIP: to undo the grey plug, slide the still connected joint off the little spigot first, then undo. Or do it like I did and skin the backs of your hands.

[Kaz-kzukNA1]

Hi, Geoff.

CEL #66 is for the electronics circuit related to the O2 sensor Rear Bank AFTER (secondary, downstream) the CAT.
It could be the sensor itself but also the loose connection or wire damage between the ECU and the O2 sensor could trigger this.

You can check the O2 sensor with multimeter but it’s not easy getting to the connector even with the small hand.

If you had any services involving the access around the rear valve cover recently, please double check that the connectors are securely locked.
There are three O2 sensor connectors at the rear valve cover and the 2 x secondary ones are hard to reach from the under/side of the car even keeping the car on the lift.
Hence, from time to time, I saw connectors not being fully locked.

Please never use UK year model when ordering the parts around the exhaust manifold/back box area from US because of the different timing of the OBD2/EOBD enforcement.
You will end up with wrong spec parts resulting in too short cable or something that won’t fit.

Also, on the later-later model, the CAT/header spec was different between UK and US and thus, the O2 sensor cable length was different between the two country spec.
You will need to change the routing of the cable slightly on certain UK models.


For the secondary O2 sensor, although the connector housing looks the same, the actual terminal inside the connector is different between the front and the rear bank so you must order the correct replacement sensor.
If I remember correctly, I think front secondary uses male terminal whereas the rear secondary uses the female one.


The best way to order the O2 sensor from US is to find out the Honda parts no for your existing sensor and cross reference it at the sparkplugs.com.

If you can email me your VIN, I can look it up for you.


Kaz

[Problem Child]

hi, geoff.

Cel #66 is for the electronics circuit related to the o2 sensor rear bank after (secondary, downstream) the cat.
It could be the sensor itself but also the loose connection or wire damage between the ecu and the o2 sensor could trigger this.

You can check the o2 sensor with multimeter but it’s not easy getting to the connector even with the small hand.

If you had any services involving the access around the rear valve cover recently, please double check that the connectors are securely locked.
There are three o2 sensor connectors at the rear valve cover and the 2 x secondary ones are hard to reach from the under/side of the car even keeping the car on the lift.
Hence, from time to time, i saw connectors not being fully locked.

Please never use uk year model when ordering the parts around the exhaust manifold/back box area from us because of the different timing of the obd2/eobd enforcement.
You will end up with wrong spec parts resulting in too short cable or something that won’t fit.

Also, on the later-later model, the cat/header spec was different between uk and us and thus, the o2 sensor cable length was different between the two country spec.
You will need to change the routing of the cable slightly on certain uk models.


For the secondary o2 sensor, although the connector housing looks the same, the actual terminal inside the connector is different between the front and the rear bank so you must order the correct replacement sensor.
If i remember correctly, i think front secondary uses male terminal whereas the rear secondary uses the female one.


The best way to order the o2 sensor from us is to find out the honda parts no for your existing sensor and cross reference it at the sparkplugs.com.

If you can email me your vin, i can look it up for you.


Kazjhmna2********1

[Problem Child]

jhmna2********1

Thanks editing the VIN Kaz, never thought!

[Problem Child]

Thanks editing the VIN Kaz, never thought! Just thinking, is it worthwhile getting both sets of sensors done at the same time. Labour at Norton Way is only 1/2 hour job, so wondered if there is any benefit to getting both done (accepting that Labour will be more)

[Kaz-kzukNA1]

Hi, Geoff.

There are lots of 'bot' hovering over the internet such as these car forums and they are looking for specific info and wording so best not to post private info that can be used for other purpose. It's almost impossible for me to delete the cached info but better than doing nothing.


Based on the information, your OEM parts no. for the Rear bank Secondary O2 sensor is 36542-PR7-A01.

For this, you can order one of the following from sparkplugs.com in US.
Just to be sure, please measure the cable length of your existing sensor but I never had any problems ordering the parts by using their cross-reference chart.



NTK #24061: about US$50, cable length 580mm, OE connector already fitted, female terminal.
Denso #234-4092: about US$40, cable length 595mm, OE connector already fitted, female terminal.




I prefer NTK but the OEM sensor on our NSX is from Denso.

Both are probably the most reliable ones on the market.

Kaz

[Problem Child]

Hi, Geoff.

There are lots of 'bot' hovering over the internet such as these car forums and they are looking for specific info and wording so best not to post private info that can be used for other purpose. It's almost impossible for me to delete the cached info but better than doing nothing.


Based on the information, your OEM parts no. for the Rear bank Secondary O2 sensor is 36542-PR7-A01.

For this, you can order one of the following from sparkplugs.com in US.
Just to be sure, please measure the cable length of your existing sensor but I never had any problems ordering the parts by using their cross-reference chart.



NTK #24061: about US$50, cable length 580mm, OE connector already fitted, female terminal.
Denso #234-4092: about US$40, cable length 595mm, OE connector already fitted, female terminal.




I prefer NTK but the OEM sensor on our NSX is from Denso.

Both are probably the most reliable ones on the market.

Kaz
Thanks, Kaz
Yes, that's the Part No that Brian Smith at Norton Way has quoted, although at £398 I will be buying it somewhere else other than HUK. Next question was which brand, from the research I have done the NTK one seems to have a good reputation so that's what I was going for. Is it worth doing all the sensors together?

[Kaz-kzukNA1]

There is not much duplicated procedures when replacing the front and rear bank O2 sensors so it won’t save much in doing other sensors at the same time.

For your year model, if you have already covered about 60K miles with your primary (upper stream, before CAT, sensor1, etc) sensor, then you may want to replace both primary ones even they are not failed because the delivery charge won’t change a lot from US for sending extra one or two sensors.

However, if your total mileage is well below 60K miles or if you are talking about the secondary sensor, then personally, I’ll just leave [Edit: the primary ones until they fail or cover enough mileage. For the secondary ones, I'll just leave them until they trigger the CEL because as far as I know, the EFI control around NSX era was not that complicated/powerful enough to utilise the secondary sensors for any controls apart from monitoring the CAT performance.]

O2 sensor will fail or the output signal will shift eventually during your ownership and the timing depends on many factors such as your engine condition, driving environment, fuel quality, etc.
It may fail tomorrow or it may last another 10+ years.

The best we can do is to use good quality fuel and use the car regularly.

Kaz

[Problem Child]

Hi, Geoff.

There are lots of 'bot' hovering over the internet such as these car forums and they are looking for specific info and wording so best not to post private info that can be used for other purpose. It's almost impossible for me to delete the cached info but better than doing nothing.


Based on the information, your OEM parts no. for the Rear bank Secondary O2 sensor is 36542-PR7-A01.

For this, you can order one of the following from sparkplugs.com in US.
Just to be sure, please measure the cable length of your existing sensor but I never had any problems ordering the parts by using their cross-reference chart.



NTK #24061: about US$50, cable length 580mm, OE connector already fitted, female terminal.
Denso #234-4092: about US$40, cable length 595mm, OE connector already fitted, female terminal.




I prefer NTK but the OEM sensor on our NSX is from Denso.

Both are probably the most reliable ones on the market.

Kaz

Finally got around to ordering this part. On the off chance that the price difference wasn't too much I called Honda Oxford (Johnsons). Firstly they wanted £400 for the part, and said that they would only fit Honda parts to the car because the "system" would reject anything else. They also said that if I put it in for a service and found any non Honda parts they would remove them!...They have just lost a customer. I then called Brian Smith at Norton Way and got completely different response. Yes both the Denso and the NTK products would fit and be OK; he'd be happy to fit the part (£40 labour). Imported the part from sparkplugs.com for $34 and $44 post. Oxford Honda can go and HUK themselves!

[britlude]

They also said that if I put it in for a service and found any non Honda parts they would remove them!...

lucky escape then, you would have lost your wheels.... stereo.... rear wing.... lol

[Problem Child]

lucky escape then, you would have lost your wheels.... stereo.... rear wing.... lol

Car booked in to have the 02 sensor replaced at Norton Way on Friday (assuming it arrives from the UK in time). If it doesn't will the faulty O2 sensor result in a failed MOT?

[NSXGB]

Car booked in to have the 02 sensor replaced at Norton Way on Friday (assuming it arrives from the UK in time). If it doesn't will the faulty O2 sensor result in a failed MOT?

AFAIK it will only fail if it's causing your emissions to run bad.

[Problem Child]

AFAIK it will only fail if it's causing your emissions to run bad.

at Norton way today to have the sensor fitted and then a new MOT. Got to say what great customer service....sky tv, free WiFi and a cafe on site serving complementary coffees. Just tucking into a lovely latte and a freshly made bacon and egg sandwich!

Another NSX outside....K50NSX. Looks like its been here a while

[Problem Child]

at Norton way today to have the sensor fitted and then a new MOT. Got to say what great customer service....sky tv, free WiFi and a cafe on site serving complementary coffees. Just tucking into a lovely latte and a freshly made bacon and egg sandwich!

Another NSX outside....K50NSX. Looks like its been here a while

Flew through its MOT today...no advisories, nothing!

[Senninha]

So having read the thread on this topic (thanx Simon) I thought I'd try the US supplier mentioned ... However, as it won't register a UK postcode I was forced to look elsewhere ... So over to our friends at fleabay.

searched by the part numbers advised above and if all goes well, postie should be at my door in 7days and then it's out with the spanners ....

[Kaz-kzukNA1]

Hi, Senninha.

If you tried sparkplugs.com, surprised that their website didn't register the UK post code.
Never had problem with the delivery to UK address.

Last time when I ordered NTK #24172 (not the same one as yours), it came in the same NTK package but they changed the way they seal the box and also additional sticker/tape was applied.
If the box was opened, it could be noticed.
Not much difference for me as the sensor itself is in a sealed bag and because of the way NTK delivers their sensor with specific grease applied to the thread with protector cover or included in a separated sachet, can be easily identified.

Amazon US delivers the NTK sensors through their AmazonGlobal program with import fee pre-paid but unfortunately, they don’t deliver some of them for some reason.
One time, I tried NTK #24172 from them but they won’t deliver it to UK.
Other shopfronts do ship to UK but I prefer delivery through amazon.
Never tried Denso one from amazon so that could be another option.

Rockauto is good for personal DIY purpose and probably the cheapest but I don’t know their batch control so prefer sparkplugs.com.


Hope you will get the correct parts as secondary sensor has different terminal type (male/female) depending on the bank.

Kaz

[Senninha]

Hi, Kaz

Thank you for your reply. The supplier has sent me shipping details so it's on it's way. Providing the details are correct then I'm expecting a plug and play item to arrive.

Once I have the delivery and know all is in order I'll share the supplier details and pricing.

regards, Paul

[NSXGB]

Rock Auto also sells the NTK sensors, I just ordered 2 x #24172 for £66 shipped.

[Pride]

Cheers again Simon, any other suggestions on saving a few bob on the parts??:)

12964

[NSXGB]

ill save them for another day. ;)



Cheers again Simon, any other suggestions on saving a few bob on the parts??:)

12964

[NSXGB]

Rock Auto also sells the NTK sensors, I just ordered 2 x #24172 for £66 shipped.

Received today and no customs charges, bargain even with the poor current exchange rate.

[Senninha]

Received today and no customs charges, bargain even with the poor current exchange rate.

Received mine today...



Genuine NGK / NTK # 24061 Oxygen Sensor (http://rover.ebay.com/rover/0/e12429.m43.l3160/7?euid=fd3a76d0aea14bff8fbc3451030146e5&bu=43125354306&loc=http%3A%2F%2Fpages.ebay.com%2Flink%2F%3Fnav%3D item.view%26id%3D200862112055%26alt%3Dweb%26global ID%3DEBAY-GB%26referrer%3Dhttp%253A%252F%252Frover.ebay.com% 252Frover%252F0%252Fe12429.m43.l3160%252F7%253Feui d%253Dfd3a76d0aea14bff8fbc3451030146e5%2526bu%253D 43125354306%2526cp%253D1%2526sojTags%253Dbu%253Dbu )


Sold for: US $15.95


Item number: 200862112055



no surcharges, so just have to install now ...