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Discussion Starter · #1 ·
Morning all

Quick question this time
I found a guide on cleaning lambda sensors on-line.

It involves soaking them fully submerged in petrol overnight and giving them a light brush with a soft tooth brush the next morning before re-fitting. As I've had a previous fault which I have turned off, I'm thinking if it comes back on I might try this (given that they seem to be at a minimum 55quid ea and that's on a CP4L sale!)

Is this a valid option to try before having a to buy new!?

Thanks
 

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Personaly I've found that any sensor that needs "cleaning" will fail so i think it's a waste of time. If you can see a part number on the cable on yours then try ebay first as that can work out cheaper.
 

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Agree with that. Sensors only tend to develop deposits if the heater coil fails (would put management light on) or they become degraded and start switching slowly which means it runs rich and this causes deposits.

O2 sensors (including wideband sensors) have a design life of 100000 miles. They may last longer (life span is better than 15-20 years ago) but its really a bit of a gamble.

On Euro 3 or later, the post cat sensor (JTS has 2) is only for cat monitoring and only need changed should the heater coil fail. It is the pre cat sensors which control fuel trim.

The pre cat wideband sensors on the JTS switch faster than the old Zirconia type and are assessed by output voltage rather than speed of voltage fluctuation (which is around 1 hertz for older sensors).

Older Bosch type sensors were noted to switch faster than the NGK, NTK branded sensors. That may have changed but even as recently as 3 years ago, I noted an old Bosch switching faster than a new NTK which is why I fitted Bosch wideband sensors (known good supply chain) to my JTS at 101k. I noticed the output voltage on the old ones appeared similar to the new one so they appear to be in good shape. I may still have the old ones in the garage.
 

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Discussion Starter · #4 ·
The eml hasnt come back on yet but there is a slight stuttering now and again. Particularly when cold and when hardly on the throttle.
If they do fail perhaps the pair in your garage could find their way to mine at some point for a fee!?
 

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Discussion Starter · #6 ·
I'll get a look tomorrow and let you know.

EML light hasn't come back on? What was the code?
I cant remember Fruity. I remember it stated Lambda1 and Lambda 2 fault/fail or something like that. The live voltage was just over 2volts for each. It was not exactly the same if memory serves. One was about 2.2v and the other 2.1v and there was a very small variation like 2.18-2.22 on the 1st as an example
 

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Discussion Starter · #7 ·
I'll get a look tomorrow and let you know.

EML light hasn't come back on? What was the code?
I cant remember Fruity. I remember it stated Lambda1 and Lambda 2 fault/fail or something like that. The live voltage was just over 2volts for each. It was not exactly the same if memory serves. One was about 2.2v and the other 2.1v and there was a very small variation like 2.18-2.22 on the 1st as an example
Just to add...my fuel economy seems appropriate. Ive worked it out myself as the computer is overestimating....surprise surprise!
Its about 33.6mpg. A fair amout of town running though early and late each day as my shifts are long. Its not nose to tail. Then ill take it out on a 20mile run round local country roads a couple of times a week due to the aforementioned low speed runs and give it a bit of an Italian tune up. Last night, judging roughly by how much the ecu is overestimating, i covered 22miles and got 26mpg. A gallon of petrol well spent :0)
 

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Just to add, I had a couple go as I'd managed to contaminate them with silicon spray - no amount of cleaning, high revs or heating with a torch got them working again - I bought a pair of good used ones from Autolusso as I wasn't sure it wasn't a wiring fault at the time - they lasted me the rest of the 8 years I had the car.
 

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Discussion Starter · #9 ·
Right fruity
Max i could get out of it was 401kg/hr
The errors, whilst the eml is not on, are still there. Stupidly i didnt note them but from memory its p0420 and p0430. Maybe new or better lambdas and better fueling will increase the output a bit.

Worryingly , my temp gauge is correct and 1st fan speed does not come on till 96oC. I wonder if this can be recalibrated somehow using the software.

Ive ordered a bluetooth obd cable and downloaded torque pro. Ill do a couple of 0-60 runs in due course and see how the drop in the maf reading translates to horsepower
 

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The temperature trigger is set, AFAIK. Are you sure it is fan 1st speed (as it seems more like high speed). Anyway, I did a thread which is in the help section (top of forum) where I went into the fan stuff.

I have had the P0420 and P0430 codes. That in itself is nothing particularly to worry about as I had this after doing EVERYTHING. The JTS management is set a bit too tightly and once of the benefits of a Squadra remap is the triggers for the cat codes are relaxed a bit for real world conditions. It is more likely to be an injector issue but frankly, I wouldn't worry as they are triggered occasionally when dribbling along at around 40mph.

Haven't had a chance to look for sensors as yet but generally they should see 4.0+ volts at maximum attack and around 0.5 volt on overrun.
 

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Discussion Starter · #12 ·
The temperature trigger is set, AFAIK. Are you sure it is fan 1st speed (as it seems more like high speed). Anyway, I did a thread which is in the help section (top of forum) where I went into the fan stuff.

I have had the P0420 and P0430 codes. That in itself is nothing particularly to worry about as I had this after doing EVERYTHING. The JTS management is set a bit too tightly and once of the benefits of a Squadra remap is the triggers for the cat codes are relaxed a bit for real world conditions. It is more likely to be an injector issue but frankly, I wouldn't worry as they are triggered occasionally when dribbling along at around 40mph.

Haven't had a chance to look for sensors as yet but generally they should see 4.0+ volts at maximum attack and around 0.5 volt on overrun.
If the software is right its fan one. I was pottering about with engine and i ticked the two fan options and the engine temp just to see(im only allowed to choose 4 with the free version)
Fan 1 came on as i was watching the screen and temp was 96.2oC. The dial seemed to indicate the correct temp. Can i add that the fan blades are SHAAARP! Maybe not indicative of a fan thats been in the car for 91k!? But im not certain if the blunt over time.

Funny you should say "dribbling along" as thats exactly what i was doing in 5th the first time when the eml beeped at me.

I guess the voltage readings im seeing in the lambdas suggests theyre broken with a capital 'F'!! If you find your old ones pm me. If theyre gone i might just have to go for a couple of new ones
 
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