E34 without O2 Sensor have 1221 Error Code

[redled]

My 1992 525i e34, US version M50 non-vanos engine have check engine light permanently while driving. The error code on its OBC is 1221 which is oxygen sensor. But this version is without O2 sensor and catalyst from the factory. What are the possibilities to have this error code and check engine light.

[Tiger]

Reset the DTC and see if it reappears.

[shogun]

a 1992 E34 US version without oxy sensor and without cat?
let me know the VIN and I will check that out.
So far I have only seen U.K. and Italian spec cars without cat, as that was an option in these countries in these days, but USA in 1992?
I thought almost all gasoline cars in USA were equipped with cats since around 1975?

[redled]

VIN- BF97758, in realoem there is O2 sensor and cat, but actually no. The entire exhaust system of the car is all original.

[shogun]

Nothing mentioned in the VIN decoder that the car came without cat originally ex factory. Normally in case of U.K. cars that is mentioned.

VIN WBAHD531XNBF97758
Type code HD53
Type 525I (USA)
E series E34 ()
Series 5
Type LIM
Steering LL
Doors 4
Engine M50
Displacement 2.50
Power 141
Drive HECK / rear
Transmission MECH
Colour ISLANDGRUEN METALLIC (273)
Upholstery (0409)
Prod.date 1991-12-16
S242A FAHRERAIRBAG MIT SERIENKRANZ(PUR) Steering wheel airbag
S288A LEICHTMETALLRAEDER BMW light alloy wheel, cross spoke 29
S428A WARNDREIECK Warning triangle and first aid kit
S458A SITZVERSTELLUNG ELEKTR.FAHRER/BEIF. Electr. front seat adjustment
S472A MITTELARMLEHNEN VORN FAHRER/BEIF. Armrest, front, driver/passenger
S640A AUTOTELEFONVORBEREITUNG Preparation f tel.installation universal
S686A ANTENNENDIVERSITY Antenna-Diversity
S694A CD-WECHSLER VORBEREITUNG Provisions for BMW 6 CD changer

[whiskychaser]

My Feb '92 525i M50 NV went to the breaker's a short time ago so feel free to use the VIN: GA11907. That certainly left the factory without a cat/O2 sensor and unlike yours, you can see they are not listed in realoem. I dont think ZA bothered with emissions until about 2005 :-) BMW probably used the same ECU with software differences for with/without CAT.

[shogun]

That was assembled in ZA. Not much data available in VIN decoder

VIN ZBAHD68090GA11907
Type code HD68
Type 525I (ZAF)
E series E34 ()
Series 5
Type LIM
Steering RL
Doors 4
Engine M50
Displacement 2.50
Power 141
Drive HECK
Transmission AUT
Colour ( *)
Upholstery ( *)
Prod.date 1992-02-18

[whiskychaser]

Yes, I contacted BMW ZA but they couldnt provide any more information than what you posted. It is a little poor when they didnt even record the colour of the car :-) The VIN plate said it was an AHL. BMW ZA had to contact Germany about that and confirmed it was similar to what the UK calls 'SE'. I have only seen HL it applied to a 6 series! Anyway, getting a bit OT.

Has the car had an ECU change or electrical issue recently?

[Bill R.]

If its a US version then it definitely had a o2 sensor and a cat in 1992

[myles]

I had a UK import 525i without cat and o2 sensor. This is how it was listed on a vin decoder. I believe that your car would have left the factory with the cat and o2 sensor.

I actually added the cat and sensor to this car and it ran so much better. I took the front exhaust section from a wrecked car, so it was a straight bolt on and plug in job.

Type

Value
VIN WBAHC22090BK97614
Type code HC22
Type 525I (EUR)
E series E34 ()
Series 5
Type LIM
Steering RL
Doors 4
Engine M20
Displacement 2.50
Power 125
Drive HECK
Transmission AUT
Colour GLETSCHERBLAU METALLIC (280)
Upholstery (0271)
Prod.date 1990-01-29

Close Options
Code

Description (interface)

Description (EPC)
S200A KATALYSATOR - ENTFALL without catalytic converter
S219A SPORT-LEDERLENKRAD Leather-covered sport st. wheel 380 mm
S288A LEICHTMETALLRAEDER BMW light alloy wheel, cross spoke 29
S314A FRONTSCHEIBENWASCHDUESEN BEHEIZT Door mirror, driver lock, heated
S401A SCHIEBE-HEBEDACH, ELEKTRISCH Lift-up-and-slide-back sunroof, electric
S411A FENSTERHEBER,ELEKTRISCH VORN/HINTEN Window lifts,electric,front/rear
S428A WARNDREIECK Warning triangle and first aid kit
S472A MITTELARMLEHNEN VORN FAHRER/BEIF. Armrest, front, driver/passenger
S498A KOPFSTUETZEN IM FOND Headrests mechanically adjustable, rear
S520A NEBELSCHEINWERFER Fog lights
S570A STAERKERE STROMVERSORGUNG Reinforced power supply
L812A ENGLAND/IRLAND AUSFUEHRUNG NATIONAL VERSION GREAT BRITAIN
S850A ZUSAETZL. TANKFUELLUNG EXPORT Additional Export tank filling
S869A RADIOVORBEREITUNG ZG/ZZ Radio preparation for ZG/ZZ
S925A VERSANDSCHUTZPAKET Dispatch protection pack

[redled]

My Feb '92 525i M50 NV went to the breaker's a short time ago so feel free to use the VIN: GA11907. That certainly left the factory without a cat/O2 sensor and unlike yours, you can see they are not listed in realoem. I dont think ZA bothered with emissions until about 2005 :-) BMW probably used the same ECU with software differences for with/without CAT.


Ill'd take a look on your VIN in realoem and that is exactlly what exhaust system installed in my car, parts# 18101728445.
Realoem give a wrong info on my VIN. By the way the car is US version shipped in the Philippines.

[whiskychaser]

Ill'd take a look on your VIN in realoem and that is exactlly what exhaust system installed in my car, parts# 18101728445.
Realoem give a wrong info on my VIN. By the way the car is US version shipped in the Philippines.
I doubt you have that actual part number as it is exclusive to S Africa. But nothing to say somebody didnt fit something very similar to your car. The issue though is that your ECU is expecting a signal from an O2 sensor and isnt getting one. The only way I can see the fault/CEL going away is if you fit a cat/O2 sensor or alter the software in the ECU

[BlackOnBlack]

If you need another to check..my vin is GB34488;
It's a 06/92.
525i M50 non-vanos;
Always has had O2 and cat.

[whiskychaser]

VIN WBAHD5311NGB34488
Type code HD53
Type 525I (USA)
E series E34 ()
Series 5
Type LIM
Steering LL
Doors 4
Engine M50
Displacement 2.50
Power 141
Drive HECK
Transmission MECH
Colour SCHWARZ 2 (668)
Upholstery (0325)
Prod.date 1992-06-11



Options

Code Description (interface) Description (EPC)
S240A LEDERLENKRAD Steering wheel, leather
S458A SITZVERSTELLUNG ELEKTR.FAHRER/BEIF. Electr. front seat adjustment
S472A MITTELARMLEHNEN VORN FAHRER/BEIF. Armrest, front, driver/passenger
S553A BORDCOMPUTER IV MIT FERNBEDIENUNG On-board computer IV with remote control
S640A AUTOTELEFONVORBEREITUNG Preparation f tel.installation universal
S686A ANTENNENDIVERSITY Antenna-Diversity
S694A CD-WECHSLER VORBEREITUNG Provisions for BMW 6 CD changer
S818A BATTERIEHAUPTSCHALTER Battery master switch
S925A VERSANDSCHUTZPAKET Dispatch protection pack

Looks like they dont even bother to mention an O2 sensor if it for the US market

[BlackOnBlack]

I just did some searching and found this site from one of Shoguns old posts that notes "Catalyzer" at the end:
BMW VIN Decoder - By Mitsuhiko Kanekatsu (http://www.bmw-z1.com/VIN/VINdecode-e.cgi)

Chassis number GB34488
Vehicle code HD53
Series E34
Model 525i ( 525i M50 )
Body type saloon
Catalog model USA
Production date 1992 / 06
Engine M50
Transmission Manual
Steering Left
Catalyzer YES

[shogun]

In general the VIN decoder does not mention an item which is standard, the items listed are just the optional extras.

[redled]

Yes, I contacted BMW ZA but they couldnt provide any more information than what you posted. It is a little poor when they didnt even record the colour of the car :-) The VIN plate said it was an AHL. BMW ZA had to contact Germany about that and confirmed it was similar to what the UK calls 'SE'. I have only seen HL it applied to a 6 series! Anyway, getting a bit OT.

Has the car had an ECU change or electrical issue recently?


Never replace the ECU, replace one ignition coil before. There is also a relay for O2 sensor color orange, ill try to unplug it and start the car, the engine would not run. How to alter the ECU, it is just by changing its chip?

[whiskychaser]

If it has that relay, there is no way it ever left the factory without a cat. Yes, you will have 3 relays in the ebox - main, fuel pump and O2 sensor. Of course, mine only had the first two. I cant explain why your car didnt throw the CEL before or how to go about changing the ECU software. The simplest solution may be a trip to the breakers to get a cat? If you fit one, the car will probably run better, use less fuel and have a cleaner exhaust.

[genphreak]

In addition to what everyone else said:

You only have the relay if it has a 4 wire sensor (it pre-heats the O2 sensor to operational temperature at start time). All M50s and M60s have 4 wire sensors, so all cat versions should have the relay. Check for that before deciding your car came from the factory without the cat as cars can get messed with in strange ways over the years.

An example might be
Plenty of people get bad exhausts and buy pre-loved replacements from wreckers who buy parts from overseas. Few use part references as anything other than to work out what might fit and run, rather than what will fit or work properly.

If your car was non-katalyst;
- you may have a faulty coil. Engine will not run right, may be intermittent and heat related.
- you may have a faulty ECU. Burnt out transistor/s. May still work intermittently though- again same symptoms as having bad coil/s.
- you may need a non-kat ROM chip (check the ECU part number in the ETK parts manual).
i. If it is (your problem is above) and you are able, please copy the chip and share it with me- I need one!)

If you have a kat version ECU maybe the ECU was swapped at some point (unless it was a factory kat version). Like me, you will need a ROM chip with the right fuel map to make it run properly and possibly stop throwing errors. A good option might be a Miller performance WAR chip (http://millerperformancecars.com) which you can self-program to match the exhaust (you can even save sports and economy mode fuel maps which you can switch on the fly :-).

Other far less likely possible causes:
Engine coolant temp sensor (ECU one nearest the driver, not the gauge one)
Crankshaft sensor (CPS)
Cam sensor
Knock sensor

[redled]

I'll check

[Dave M]

1991 CAN M50 with Cat from factory. Cat was removed by the previous owner who had a (very thick walled) straight pipe welded in with a thread for an O2. Car runs as it should.

Dave

http://img.photobucket.com/albums/v11/dave_macisaac/Bimmer/Exhaust/Exhaust.jpg (http://smg.photobucket.com/user/dave_macisaac/media/Bimmer/Exhaust/Exhaust.jpg.html)

[whiskychaser]

1991 CAN M50 with Cat from factory. Cat was removed by the previous owner who had a (very thick walled) straight pipe welded in with a thread for an O2. Car runs as it should.

Dave



Now that I can understand. But as OP states he has an OE non-cat front box, there is nowhere to put the O2 sensor. I may not be the only assuming OP was indicating he doesnt have an O2 sensor either. Perhaps he can confirm?

[Tiger]

REDLEF, either install a new aftermarket cat and O2 sensor

or

cut a hole in the straight pipe, weld in a nut for the O2 sensor thread and put O2 sensor in.

[Dave M]

REDLEF, either install a new aftermarket cat and O2 sensor

or

cut a hole in the straight pipe, weld in a nut for the O2 sensor thread and put O2 sensor in.

This is why I posted my photo. Also, if I had to guess, I would say the vehicle came with a cat.

Dave

[redled]

7822

This is the exact parts installed in my car. No modification or repair yet. Original parts.
Where can I put a hole for the sensor and do you think it will work w/out cat?

[Tiger]

Hmmm... since we know the car is US import... the ECU is probably US version for cat... do you think you can source a ECU of similar engine in your country? This might be easier.

Putting an O2 sensor would be just at the bend where the pipe comes down from engine and straightens out to the muffler.

[whiskychaser]

7822

This is the exact parts installed in my car. No modification or repair yet. Original parts.
Where can I put a hole for the sensor and do you think it will work w/out cat?

I think Tiger already answered that and Dave M gave you a work around. I would go with Tiger's option a. as:

1. You are going to blow a hole in a 20+ year old exhaust pipe if you try to weld it
2. If you fit the O2 sensor to a straight pipe before the silencer box it is only going to read off 3 cylinders
3. IMHO that is what it supposed to have to make the car run properly :-)

[redled]

If I can't find CEU here, there is no option I have to install sensor. Where is the electrical connection for O2 sensor located and how to know if it is for that sensor.

[genphreak]

Talk to millerperformance.com, someone on the WAR chip forum might be able to share a suitable bin file with you.

To add an O2 sensor you would have to add the factory cat and engine pipe assembly (easy to source in the US- all M50 powered 525is had them) and they come with the sensor, wire and plug. Ask for the wire support/metal encasement, plastic bolts and so on too.

Does your car have the female side of the sensor plug on the LHS of the engine? It's about 40mm in diameter, goes through a black metal bracket mounted down under the intake.

[redled]

Yes there is. Its hard to find factory cat and engine pipe assembly here in the Phils.
I might do what Dave did in his car.

[shogun]

no need to find a factory cat. A universal steel cat is better, takes less space and even might give some more HP.
Just search in the net for Universal High Flow Catalytic Converter

But I assume in the Philippines it does not matter if there is a cat installed or not?

Then there is another option: Oxygen Sensor Simulator
Oxygen Sensor Simulator (http://bobblick.com/techref/projects/o2sensor/o2sim/o2sim.html)

Or the version Dave made, maybe the easiest, welding a O2 sensor thread into the pipe.
Thread size I believe it is M18 x 1.5. Or use a thread chaser and make the thread into the pipe.
Go to your local parts store and ask for an O2 sensor thread chaser.

[redled]

Yes I will copy Dave's version anyway you are right there is no restriction here about environmental compliance.

[Dave M]

Not sure if you covered this, but you will need to find the wiring harness that the new O2 sensor will connect to. If I recall correctly, the end of mine is clipped somewhere below the starter.

Dave

[632 Regal]

He doesn't have original O2 wiring? It must be stuffed away somewhere. In general if you want to ad 1 O2 sensor it would go right before the mufflers. If you have 2 O2 sensors the reading one goes right infront of the muffler and the other after. The secondary O2 sensor just has to have a reading different than the first so it wont trip the CEL code.

[redled]

There is a threaded plug for 4 wire sensor below the starter.
Can I use any brand of sensor, is the reliability with different brand the same?

[Tiger]

Any brand will do... just make sure you get the one with wire harness on it rather than universal.

[genphreak]

They can be broken if the box is dropped so it may pay to use a half-decent supplier.

Avoiding universal is important, don't go soldering wires, they are stainless steel and can get hot enough to melt any type of solder. Hella and Bosch make them with the required (about 35mm diameter) Bosch 4 wire plug, just search the web by part number.

If you have a bung already in your pipe (is that what you meant by under the starter?), you will need to drill it through and/or tap it. Beware as you may hit stainless steel. Whatever happens, beware welding- you need someone good to weld stainless engine pipes. If any part you need to weld is rusty and does not clean up well, the welding will be challenging (stainless is seldom quick to rust though)...

[genphreak]

no need to find a factory cat. A universal steel cat is better, takes less space and even might give some more HP.
Just search in the net for Universal High Flow Catalytic Converter

Are you sure, Erich? On many sixes people seem to end up using a single large bore universal rather than the two that BMW fit- and the BMW ones are wider and lower to fit the tunnel without hanging down. They are also better insulated than the Universal ones. If you use one and it isn't shielded as well, it could do things like cause grass fires if you leave your car on the side of the road (http://www.exploroz.com/Forum/Topic/70155/Grass_fires_under_vehicles.aspx)one day...

http://www.exploroz.com/Utilities/showImage.aspx?i=%2fUploads%2fMembers%2f143056.25% 2fForum%2fPic_12__TN800.jpg&w=500

[Dave M]

They can be broken if the box is dropped so it may pay to use a half-decent supplier.

Avoiding universal is important, don't go soldering wires, they are stainless steel and can get hot enough to melt any type of solder. Hella and Bosch make them with the required (about 35mm diameter) Bosch 4 wire plug, just search the web by part number.

If you have a bung already in your pipe (is that what you meant by under the starter?), you will need to drill it through and/or tap it. Beware as you may hit stainless steel. Whatever happens, beware welding- you need someone good to weld stainless engine pipes. If any part you need to weld is rusty and does not clean up well, the welding will be challenging (stainless is seldom quick to rust though)...

He's referring to the plastic threaded O2 wire harness he needs to connect with the new one. He may need to use your welding advice further downstream.

[genphreak]

Duh! Silly of me...