Error Code 21

[GazS14]

I've just got myself a 1991 LS400 (247k miles!) and have been using this site to help me with some of the maintenance that may have been missed by the former owner.

This afternoon I cleaned out the throttle body and found that the car is now showing error code 21 (main O2 sensor). This error wasn't there this morning so I'm wandering what I could have done to cause it. Could it simply be as a result of some of the deposits I've flush out of the throttle body working their way through the system and fouling the sensor? The car seems to now be running very rich and does not start well from cold.

Does anyone have any ideas?

[GazS14]

Is the car safe to drive with this error (apart from overfueling!)

[aido]

Should be ok mate, just like you say it'll be running rich as chuff now.

The o2 sensor will have been coated in a film of the cleaning stuff and all the deposits so probably dead, you could always rip it out and sit it in lemon juice for a day or two as that might sort it.

Might be worth trying a universal o2 sensor and hooking that up as they're cheap and it'll save you a fortune in petrol with the milage you'll be doing!!

[GazS14]

Should be ok mate, just like you say it'll be running rich as chuff now.

The o2 sensor will have been coated in a film of the cleaning stuff and all the deposits so probably dead, you could always rip it out and sit it in lemon juice for a day or two as that might sort it.

Might be worth trying a universal o2 sensor and hooking that up as they're cheap and it'll save you a fortune in petrol with the milage you'll be doing!!

Thanks for the advice - I'll try clean the sensors at the weekend. I've seen a few universal sensors around, is there a particular type I need?

[aido]

Honestly don't know on the LS mate - sitting it in lemon juice will probably sort it as it's been contaminated for a short while.

Think the universal one I got reads from 0v to 1v, I think some go higher, someone on here was saying something about some are 4 ohm resistance and some are 12 ohm but that bits beyond me!

Maybe one of the LS guys will know?

[GazS14]

Honestly don't know on the LS mate - sitting it in lemon juice will probably sort it as it's been contaminated for a short while.

Think the universal one I got reads from 0v to 1v, I think some go higher, someone on here was saying something about some are 4 ohm resistance and some are 12 ohm but that bits beyond me!

Maybe one of the LS guys will know?

Thanks for your help - hopefully an LS guy will be along soon!

[aido]

Actually fella according to this site the universal one will work and is 30 quid:

http://www.gendan.co.uk/oxygen_lambda_sens...exus_LS400.html

Thing is though that's a screw type one, I just had a nosey at the EPC on toyodiy.com (http://www.toyodiy.com/parts/p_E_1991_LEXUS_LS400_UCF10R-AEPGKW_8401.html?hl=89465) and it looks like the front o2 is one with a flange, if so you could get the screw type one for 30 quid and then just get a flange from a guy called Chris Wilson - I'll pm you his details if you like as that's where I got mine from and it works fine with the Bosch sensor I got. If they are actually screw types ignore the flange stuff!

The Bosch one will last longer they reckon but if you're only wanting to use it for that run you're doing just go with the cheaper one, I would anyway mate.

[aido]

This might help as well fella:

http://www.lexls.com/tutorials/EFI/mainoxygensensor.html

[GazS14]

This might help as well fella:

http://www.lexls.com/tutorials/EFI/mainoxygensensor.html

Cheers for your help mate you've done everything apart from fit them for me :winky:

It looks like they just screw in so they should be ca bit cheaper than I thought!

[aido]

That's because I'm dangerous with spanners!

It's weird as that EPC pic shows one with a flange on it, I made the same mistake when I bought mine, got the screw type and turned out I needed the bloody one with a flange on it!