1992 GTR R32 - o2 Sensor question

[Rides]

Can someone let me know the product code for OEM o2 Sensor on a GTR R32, and also where i can get a set of new ones? i was hoping to get the code so i can check to see if nissan had a similar set. Please point me in the right direction if anyone knows where to get them.

thanks in advance

also, would a bad o2 sensor put the car into limp mode after car has been fully warmed up (20 mins of driving)

[Skym]

They are NTK / NGK o2 sensors and just have "Nissan" stamped on them.

Can buy them here -

http://www.kudosmotorsports.com/catalog/ngk-ntk-lambda-sensor-oxygen-ntk-nissan-skyline-r32-gtr-rb26dett-p-1024.html

You'll need to buy 2x o2 sensors and change the plug on front o2 sensor that you buy with the plug on the front o2 sensor that's currently on your car.

From what I understand, limp mode is when you can't access Consult with stock ECU (to see, clear error codes, etc) and can happen when EPROM chip dislodges itself from a EPROM socket or main circuit board. I think ECU should run engine rich in this mode.

When unplug sensors or sensor is faulty, stock ECU uses a default value for that sensor (value / number that doesn't change). It does it with MAF's (also can activate a 2500rpm rev limiter when MAF's are disconnected), o2 sensor (slightly richer value and engine idles smooth without missing) and I think TPS.

From my experience with faulty o2 sensor, the o2 sensor becomes sluggish with readings (slow to fluctuate from lean to rich and rich to lean). Basically o2 sensor + ECU can make engine stay rich longer, pop flames from exhaust (popping sound from exhaust).

[Rides]

if indeed the EPROM chip is dislodged, it would be in limp mode right away or stay in limp mode right? if i experience limp mode after 20mins of fine driving, would you think i should be looking at mafs and not the ecu or o2 sensors?

[Skym]

It should stay in limp mode until problem is corrected. I think some get confused with "Limp home mode" (ECU using the default values for sensors and is a stock ECU only feature) and "Limp mode" where you can't access Consult, engine runs rich, etc when EPROM chip dislodges.

If still running rich when engine is warm, o2 sensors (unplugging o2 sensors makes ECU ignore o2 sensors or can disable them if have Nistune, but check with wideband afterwards to make sure engine isn't running lean), coolant temp sensor for ECU (error code on ECU and is a common problem).

When MAF failed on my car, engine idled at 1500rpm when cold, hot and had MAF error code on ECU. Replaced MAF, problem solved. Some say they get other symptoms like stalling, etc, just I haven't experienced that type of MAF failure on my car.

Knock / low octane maps are another due to engine running lean (leaking intake, exhaust manifolds, etc making engine run lean, knock or running on low octane gas).

TPS is another that can affect fueling and is a common failure part, that like o2 sensors is replaced as part of routine maintenance. o2 sensors are checked every 40-60,000kms and replaced if faulty. You hold rpm at 2000rpm and note how quick they switch (consult engine manual for procedure or search forum).

Engine manual -

http://www.jpnz.co.nz/afawcs0131170/CATID=24/SUBID=273/page=1/products.html

[Rides]

when i say limp mode, i mean the car would limit the rev to 2500rpm. and it usually happens when i've been running the car for about 20mins fine. After i turn off the car for about 2-3 hours and the engine is cool down, the rev limit "limp mode" is gone, and i can drive it fine again.

[Skym]

Probably have bad solders inside square part of one of the MAF's. It probably would explain why one of them doesn't work when hot and works when cold. If remove rubber sealant (need to buy high temp sealant to replace it), pop lid on both MAF's and check for bad solders on plug side. Engine ECU, HICAS ECU, MAF's, Speedo, aircon control unit suffer from this bad solder problem.

[Rides]

ok, i will check out maf solders first. Hopefully that will be the problem. thanks for the info. I'll keep this thread updated