Alfa Romeo Forum banner

1 - 16 of 16 Posts

·
Registered
Joined
·
6 Posts
Discussion Starter #1
Hi guys. I'm new to the forum having just brought my first Alfa, a little 147 :) I've had it five days and the mcsf has come on. The guy that I got it from has put a nasty cone filter on it straight to the maf sensor without a cold feed and it's definitely not been cleaned since its been fitted. I took it off today and cleaned it out and the warning went away.....it's back! Do you think I should change the maf sensor or could it be something else? Many thanks in advance.
 

·
Registered
Joined
·
2,370 Posts
You can buy a code reader for about £15 on ebay or buy a set of leads and download MultiEcuScan (MES) and use a laptop. Note that MES is an amazing piece of software but can be a bit frustrating to set up.

First thing is clear all codes as some may be old and unrelated.
Start the car and drive it and re-read the fault codes.
 

·
Registered
Joined
·
6 Posts
Discussion Starter #6
Reset the ecu today and that got the light to go out for about ten minutes of driving and now it's back. Do you need a fairly recent laptop to run the diagnostic software and is there a set of leads that you'd recommend?
 

·
Registered
Joined
·
6 Posts
Discussion Starter #9
Not great news. I got two codes, p0100 which is for the maf sensor which I thought was on its way out and the other is p0340....crankshaft sensor. Just checked through the old receipts I got with the car and the cam belt was do 20k ago, for £125. No water pump, no pulleys, tensioners or variator. I think that the belt is starting to slip and that's what's setting the mcsf off. Any solutions would be greatly appreciated.
 

·
Registered
Joined
·
187 Posts
I'm having 2 fault codes P0135 and P0141. I understand they are oxygen sensors. will removing the sensors get rid of the MCSF message?

The car runs fine, just that it's irritating having these messages come up
 

·
Registered
Joined
·
5,266 Posts
No, removing it will cause an error! You risk damaging the CAT as well if you have faulty lambda sensors which will hurt you come MOT time (assuming you are in the UK). The light being on will also be a fail.
 

·
Registered
Joined
·
2,757 Posts
I'm having 2 fault codes P0135 and P0141. I understand they are oxygen sensors. will removing the sensors get rid of the MCSF message?

The car runs fine, just that it's irritating having these messages come up
no.

The ECU will still throw a code as it won't be able to ''see'' the sensors if you disconnect them.

your choices are limited, buy new lambda's or live with it. point is the lambda'a are either toast or they are picking up a discrepancy, I wouldn't run the car for too long with the management lights on as your mixture most likely is outside of expected parameters.

running like ths can cause all sorts of issues , not least killing your cats.


get it sorted asap.
 

·
Registered
Joined
·
187 Posts
no.

The ECU will still throw a code as it won't be able to ''see'' the sensors if you disconnect them.

your choices are limited, buy new lambda's or live with it. point is the lambda'a are either toast or they are picking up a discrepancy, I wouldn't run the car for too long with the management lights on as your mixture most likely is outside of expected parameters.

running like ths can cause all sorts of issues , not least killing your cats.


get it sorted asap.
when u mean new lambdas, you're referring to the oxygen sensors?

emissions isn't a big deal in my country. is removing the cat a possible option? thanks for the replies btw
 

·
Registered
Joined
·
2,757 Posts
the lambda'a (yes O2 sensors) are their to help your car ecu calculate how much fuel needs to be injected by evaluating how much 02 is in the exhaust gases , along with the maf sensor and various other things they keep your engine efficient and burning fuel as cleanly as possible.

if you want remove the cat,lambda's Map sensor, fuel rail pressure sensor ...etc etc, the car will either revert to baseline settings or go into limp mode...without trying it there is no way to know what will likely happen.


yes you can remove them but it will have an effect is what I am saying...

you are better off trying to get to the bottom of the problem so your engine can run as intended, it will last longer and produce more HP with better economy (most likely)

good luck with it:thumbup:
 

·
Registered
Joined
·
2,271 Posts
The cone filters are sometimes oiled. This oil can damage the platinum wire in the maf sensor. You maybe able to clean it but it is a sealed unit. New lambdas and maf will set you back a few quid but it's what those codes are telling you is wrong so it's probably the most sensible course of action.
 
1 - 16 of 16 Posts
Top