Don't worry .
O2 means oxygen , so O2 sensor = oxygen sensor which is another name for lambda sensor.
You have a 4 cylinder in line engine so you only have bank 1.
O2 sensor 2 is the sensor after the cat.
Technical Brava 1.2 obd location and alternator lead question
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Technical Brava 1.2 obd location and alternator lead question
O2 means oxygen , so O2 sensor = oxygen sensor which is another name for lambda sensor.
You have a 4 cylinder in line engine so you only have bank 1.
O2 sensor 2 is the sensor after the cat.
Use live data and look at coolant temp with engine running , pref starting from cold,
See what it reads and if it goes up as engine warms up. Make a note so you can share with us.
When the engine warm turn off, turn back on straight away and check temperature reading live data,is temp reading same as just before switching off?
Or is it reading really cold?
Give us the numbers.
See what it reads and if it goes up as engine warms up. Make a note so you can share with us.
When the engine warm turn off, turn back on straight away and check temperature reading live data,is temp reading same as just before switching off?
Or is it reading really cold?
Give us the numbers.
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Any code that starts p0
Means the same for all manufacturers.
So almost all code readers can come up with its meaning on screen.
Codes starting p1
Mean different things for different manufactures. So not all code readers have all the different meanings programmed in , so you have to search for the meaning of FIAT P1141.
Search fiat forum
Means the same for all manufacturers.
So almost all code readers can come up with its meaning on screen.
Codes starting p1
Mean different things for different manufactures. So not all code readers have all the different meanings programmed in , so you have to search for the meaning of FIAT P1141.
Search fiat forum
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Brim987
Member
Well I found this, looks like bad news...
The reason of P1141 OBD-II Engine Trouble Code is Fuel Rail/System Pressure - Too High.
http://p1141.enginetroublecode.com/fiat-brava
The lambda is not a big deal, just slightly worse mpg I guess.
The temp sensor seems not to be a problem.
But the p1141..... oh dear.
:-(
The reason of P1141 OBD-II Engine Trouble Code is Fuel Rail/System Pressure - Too High.
http://p1141.enginetroublecode.com/fiat-brava
The lambda is not a big deal, just slightly worse mpg I guess.
The temp sensor seems not to be a problem.
But the p1141..... oh dear.
:-(
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Brim987
Member
10 minutes frantic googling later, might be the MAF sensor. 100 quid maybe?
Quote Start:
A MAF sensor that continuously over-reports or under-reports airflow into the engine will cause an engine to run rich or lean. If the engine control system is working correctly, you will probably never notice this except for a change in fuel economy. A trained technician will have to look at fuel trim status with the use of a scan tool to verify this. A MAF sensor that behaves like this will require replacement. Before replacing the sensor, however, the rest of the circuit should be checked for proper operation. If the circuit has an issue, replacing the sensor will not solve your problem.
Quote End:
I'm just worried this is a rabbit hole. Try this, try that, mechanic time, mechanic time...
The car drives perfectly, is much quicker than I expected
and is even doing over 500 miles on a tank.
Do I just go with the sticker over the engine light approach?
Should I reset the codes and see if they come back?
What does the panel think?
Quote Start:
A MAF sensor that continuously over-reports or under-reports airflow into the engine will cause an engine to run rich or lean. If the engine control system is working correctly, you will probably never notice this except for a change in fuel economy. A trained technician will have to look at fuel trim status with the use of a scan tool to verify this. A MAF sensor that behaves like this will require replacement. Before replacing the sensor, however, the rest of the circuit should be checked for proper operation. If the circuit has an issue, replacing the sensor will not solve your problem.
Quote End:
I'm just worried this is a rabbit hole. Try this, try that, mechanic time, mechanic time...
The car drives perfectly, is much quicker than I expected
and is even doing over 500 miles on a tank.
Do I just go with the sticker over the engine light approach?
Should I reset the codes and see if they come back?
What does the panel think?
Well good news you can't trust everything people put on the web.
The site you got to is total boll$$$$
Not your fault.
Do the live data test on coolant temp sensor and report results.
Unfortunately you can't always say if gauge works the ecu is getting told correct temp from sensor .
Tests will help.
O2 sensor after cat .
Yes clear codes and see if they stay cleared.
But also get under car and fund the wiring at o2 sensor , follow wires looking for damage .
Do you have a multi meter?
Unfortunately you can't always say if gauge works the ecu is getting told correct temp from sensor .
Tests will help.
O2 sensor after cat .
Yes clear codes and see if they stay cleared.
But also get under car and fund the wiring at o2 sensor , follow wires looking for damage .
Do you have a multi meter?
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Brim987
Member
Ok well I'm genuinely pleased it's total boll$$$$.
Can I ask where you found the correct info?
I'll do the temp tests ASAP.
Thanks
Steve
P.S
Yes I have a multimeter.
I don't know where I'm looking for the o2 sensor..
Can I ask where you found the correct info?
I'll do the temp tests ASAP.
Thanks
Steve
P.S
Yes I have a multimeter.
I don't know where I'm looking for the o2 sensor..
Ok well I'm genuinely pleased it's total boll$$$$.
Can I ask where you found the correct info?
I'll do the temp tests ASAP.
Thanks
Steve
P.S
Yes I have a multimeter.
I don't know where I'm looking for the o2 sensor..
Hi Steve,
Lots of googling and using experience to weigh up which results to trust.
Google took me back to several fiat forum results that while not individually conclusive eventually lead to a trust worthy result.
Just checked the wiring diagram previously linked.
Your coolant temperature sender unit that is in engine contains two sensors, one tells gauge what to read the other sends a signal to ecu. So it is entirely possible for the gauge to work but the ecu to receive no signal at all.
Jack
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Brim987
Member
>So it is entirely possible for the gauge to work but the ecu to receive no signal at all.
Curious design.
Confucius he say man with two watches never know the time..
Curious design.
Confucius he say man with two watches never know the time..
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Brim987
Member
>Lots of googling and using experience to weigh up which results to trust.
OK, it's disappointing that a device intended to decode the codes can't, even
with the manufacturer specified. Perhaps because they are model specific, but
even then it doesn't seem beyond the wit of man to use vehicle info...
Failing that, you'd hope the manufacturers would publish something helpful but perhaps they don't want home mechanics fiddling...
OK, it's disappointing that a device intended to decode the codes can't, even
with the manufacturer specified. Perhaps because they are model specific, but
even then it doesn't seem beyond the wit of man to use vehicle info...
Failing that, you'd hope the manufacturers would publish something helpful but perhaps they don't want home mechanics fiddling...
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Brim987
Member
>Give us the numbers.
I was under some time pressure so I couldn't do a full cold to full warm test but hopefully this is good enough.
After standing for 1 hour: Live data temp 37C, ran engine until 54C.
Turn off car and vs600, reconnect, restart, live data indicates 54C.
I reset the codes and they haven't come back yet (not actually driven yet though!)
I was under some time pressure so I couldn't do a full cold to full warm test but hopefully this is good enough.
After standing for 1 hour: Live data temp 37C, ran engine until 54C.
Turn off car and vs600, reconnect, restart, live data indicates 54C.
I reset the codes and they haven't come back yet (not actually driven yet though!)
Ha ha
The ecu never "sees" the temp the gauge is showing
Looks like coolant sensor is behaving correctly at the moment yay (-:
Great that engine fault light hasn't come back on , fingers xed.
Keep us in the loop with this car and how you and your boy are doing.
Jack
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Brim987
Member
>Great that engine fault light hasn't come back on , fingers xed.
The light came back on....
Boo Hiss, but to be expected I guess.
I haven't checked if the codes are all the same yet, but I expect so.
It's not going to get a service/mot until next spring so they can fix it then.
They boy loves it, those errors aren't going to hurt it in the meantime so we'll just
keep calm and carry on for now.
A huge thank you to all!
Steve
The light came back on....
Boo Hiss, but to be expected I guess.
I haven't checked if the codes are all the same yet, but I expect so.
It's not going to get a service/mot until next spring so they can fix it then.
They boy loves it, those errors aren't going to hurt it in the meantime so we'll just
keep calm and carry on for now.
A huge thank you to all!
Steve
Only just seen this thread... I've got a 1.2 Brava Y reg 2001.
As you seem to have found (?) the ODB2 connector is in its own little panel above your right knee, not by the main fuse box cover.
I've had various issues with mine over the years, it has the later (Euro 3?) setup with the 2 O2 lambda sensors and the combined exhaust / Cat "manicat" design.
Do not mix up the 2 connectors for the 2 lambdas ! It could be that the sensor has packed up (heater and signal errors) but I had an ECU problem reported with the 2nd sensor reading with an otherwise OK sensor... turns out there was a crack on a bend at the bottom of the exhaust manifold, it was letting air in and messing up the mixture being read by the sensor and fed to the ECU. I got it welded but eventually found a good replacement Fiat manicat.
Check the cooling system is clean and free of air, there are 2 black hoses that go into the bulkhead and the heater matrix behind, with the heater on and engine running remove the little knurled screws in the hoses (flow first then return) until water bubbles out.
For the MAF sensor remove all the intake hoses etc from the airbox to the inlet, and give a good spray with carb cleaner with the engine running and revving, wipe it if mucky.
These are great cars and engines when running nicely, excellent performance and economy.
As you seem to have found (?) the ODB2 connector is in its own little panel above your right knee, not by the main fuse box cover.
I've had various issues with mine over the years, it has the later (Euro 3?) setup with the 2 O2 lambda sensors and the combined exhaust / Cat "manicat" design.
Do not mix up the 2 connectors for the 2 lambdas ! It could be that the sensor has packed up (heater and signal errors) but I had an ECU problem reported with the 2nd sensor reading with an otherwise OK sensor... turns out there was a crack on a bend at the bottom of the exhaust manifold, it was letting air in and messing up the mixture being read by the sensor and fed to the ECU. I got it welded but eventually found a good replacement Fiat manicat.
Check the cooling system is clean and free of air, there are 2 black hoses that go into the bulkhead and the heater matrix behind, with the heater on and engine running remove the little knurled screws in the hoses (flow first then return) until water bubbles out.
For the MAF sensor remove all the intake hoses etc from the airbox to the inlet, and give a good spray with carb cleaner with the engine running and revving, wipe it if mucky.
These are great cars and engines when running nicely, excellent performance and economy.
Can you take a photo of your OBD ports location
I thought the had found it 'underslung' same as my marea..
I thought the had found it 'underslung' same as my marea..
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Brim987
Member
My boy just put some pics in the members' gallery...
He's very proud.
He's very proud.
