Ford Focus ST Forum banner
1 - 12 of 12 Posts

·
Registered
Joined
·
127 Posts
Discussion Starter · #1 ·
Hey guys,

Been having a few issues this week with the ST

checked my error codes and found:

P0101- MAF A circuit fault
P0133- 02 Sensor circuit slow responce
P2178- too rich off idle.

After a quick look around (and the descriptions) I figure I need to change the MAF...again and the O2 sensor aswell. Can any one tell me where the O2 sensor is?

I assume that both of these sensors failing would cause the over fueling?

I am currently running with the MAF disconnected.

Cheers

Simon
 

·
Registered
Joined
·
510 Posts
O2 sensor is the lambda sensor, not sure which one would need replaced tho

Sorry didn't say, it's in the exhaust, there's 2, one in the downpipe and one after the cat
 

·
Registered
Joined
·
127 Posts
Discussion Starter · #3 ·
O2 sensor is the lambda sensor, not sure which one would need replaced tho

Sorry didn't say, it's in the exhaust, there's 2, one in the downpipe and one after the cat
...I cant believe I didnt make the link haha good job im blonde or id have never got away with it
 

·
Registered
Joined
·
3 Posts
P0133 is Bank 1, sensor 1 so is referring to your pre cat sensor.
P2178 will be related to this...
Firstly check if your car is running rich - it may not be the sensor at fault, it may be telling the truth...
Have you got a de-cat pipe on?

Phil..
 

·
Registered
Joined
·
127 Posts
Discussion Starter · #6 ·
P0133 is Bank 1, sensor 1 so is referring to your pre cat sensor.
P2178 will be related to this...
Firstly check if your car is running rich - it may not be the sensor at fault, it may be telling the truth...
Have you got a de-cat pipe on?

Phil..
Iv got a full DS exhaust and race cat. How would I be able to check if its running rich or not?
 

·
Registered
Joined
·
1,316 Posts
If it was me, the fact that there is a MAF fault would lead me to change that first.

The MAF is the first sensor in the loop really because the fueling adjustments start with the readings taken from that sensor.

It may be that because the MAF is reporting incorrectly that the car is being overfuelled unnecessarily.

Chances are you may not even need the O2 sensor (unlikely but it is possible that the MAF alone is causing the problem), so if you have time to fault find i would either borrow a MAF to see if it sorts it, or even try and clean your's first with electrical contact spray (IPA) by spraying it lightly over the actual element in the MAF and then leaving it to dry properly and then if none of that works buy one.

again if this doesnt solve it completely and you are still showing hego sensor errors then you can shell out the £70 for a new hego sensor
 

·
Registered
Joined
·
127 Posts
Discussion Starter · #8 ·
If it was me, the fact that there is a MAF fault would lead me to change that first.

The MAF is the first sensor in the loop really because the fueling adjustments start with the readings taken from that sensor.

It may be that because the MAF is reporting incorrectly that the car is being overfuelled unnecessarily.

Chances are you may not even need the O2 sensor (unlikely but it is possible that the MAF alone is causing the problem), so if you have time to fault find i would either borrow a MAF to see if it sorts it, or even try and clean your's first with electrical contact spray (IPA) by spraying it lightly over the actual element in the MAF and then leaving it to dry properly and then if none of that works buy one.

again if this doesnt solve it completely and you are still showing hego sensor errors then you can shell out the £70 for a new hego sensor
Iv cleaned the sensor twice now, before and after re oiling the K&N. iv got a lambada on order now. like you say 70 quid and thats never been changed against 130 and iv already changed it once.

thanks for the responces !
 

·
Registered
Joined
·
1,316 Posts
How long ago did you change the MAF and the hego sensor?

Strange that they should be playing up again (i misread your first post and didnt see that you had already changed these before).
 

·
Registered
Joined
·
127 Posts
Discussion Starter · #10 ·
How long ago did you change the MAF and the hego sensor?

Strange that they should be playing up again (i misread your first post and didnt see that you had already changed these before).
Iv only changed the MAF once before about 4-5 months ago.
 
1 - 12 of 12 Posts
Top