Good Evening folks,

I have a 2009 1.4 grande punto with a suspect o2 sensor circuit fault. I am throwing codes P0130 (O2 Sensor Circuit Bank1 Sensor1) & P1135 with Torque Pro.


Car has had EML with codes for a while so I decided to replace both O2 sensors as these were straight forward enough. Faults cleared temporarily but came back after a short drive.

Therefore I feel I can rule out O2 sensors themselves and look elsewhere.


My only other line of thought is that when I replaced the O2 sensors I also changed spark plugs/coils and one of the coil connectors was damaged. I resecured it pretty well. Could this throw these codes???

If anybody has any experience of these codes together could you please shed some light?

Many Thanks in advance


Mark

Have a look here: https://www.fiatforum.com/punto-ii/353247-p1135-what-look-mes.html

Ziggy 122 was a great source of information !!


BRs, Bernie.

ps: the sensor heater can still be ok, just a bad fuse, relay, wiring ...

Thanks for the link , I'll check the resistance on heater circuit. I'll have a look for fuse diagram ?

Thanks again will keep updated

Mark

Soooo...
6ohms on O2 sensor , couldn't get meter onto heater wiring to ECU as test leads wouldnt fit into connector pins ?

Checked all fuses in engine compt and they were ok. Earth's ok as well from battery to chassis on top of valve cover.

Another symptom to report is power loss/engine stuttering around 2000-3000rpm.

This leads me to a fueling issue?

I will clean map sensor and maybe replace fuel filter as haven't changed this since weve had it.

Any other ideas most welcome ?

Cheers

Mark

Am I right in saying only diesels have a filter??

11thevans said:

Am I right in saying only diesels have a filter??

Click to expand...

No petrol have filter too .
It is likely part of in tank fuel pump.

However You really should check integrity of wiring between o2 sensor and ecu first. I do not think you have fuel issue.
A reader that can give live data of o2 sensor voltage would help you massively.

Unfolded paper clips may fit into connector block of ecu, unplug it from ecu safely before probing

To clarify you must check all wires between o2 connector and ecu connector have continuity i e very low resistance.
You can do this with a multimeter and long leads.
Disconnect ecu and o2 when doing this.

What brand o2 sensor did you fit?

I doubt very much spark plug/ coils could throw your o2 codes.

Are you still getting o2 heater circuit fault code with new o2 sensor?

Hi Jack, I've still got the old sensor so can cut connector of that and test using leads. The o2 sensors I changed didn't have a brand ? but resistance is OK at 6 ohms? And yes still throwing codes up with new sensors ?

jackwhoo said:

No petrol have filter too .
It is likely part of in tank fuel pump.

However You really should check integrity of wiring between o2 sensor and ecu first. I do not think you have fuel issue.
A reader that can give live data of o2 sensor voltage would help you massively.

Click to expand...

I've managed to set up torque to monitor sensor voltages what am I looking for specifically?

The pattern I see is sensor 1 goes high voltage and sensor 2 goes low, there are a few hiccups in the graph where sensor 2 spikes voltage on its own??

11thevans said:

Hi Jack, I've still got the old sensor so can cut connector of that and test using leads. The o2 sensors I changed didn't have a brand ? but resistance is OK at 6 ohms? And yes still throwing codes up with new sensors ?

Click to expand...

Did you fit cheapo o2 sensors from the likes of ebay?

Ignore the o2 sensor after the converter for now as you have not had a code for it.

With engine running at normal temperature. What voltage are you reading from ecu for o2 sensor ,roughly.

Then stop engine , unplug o2 sensor then tell us what the voltage reading from ecu for o2 sensor is.

11thevans said:

Hi Jack, I've still got the old sensor so can cut connector of that and test using leads. The o2 sensors I changed didn't have a brand ? but resistance is OK at 6 ohms? And yes still throwing codes up with new sensors ?

Click to expand...

Did you work the colour code of the wires on o2 sensor?
Do you have 4 wires? Two white? One grey? One black?

Check there is a decent earth connection between better and body too , not just battery to engines

jackwhoo said:

Check there is a decent earth connection between better and body too , not just battery to engines

Click to expand...

λ (O2) sensor's heater is two wires fed and the signal is returned to ECU with two wires, so it should not be sensitive to battery to boddy earthing, while A LOT of other errors and misbehavior would pop-up.

Here are some info about the λ sensors ...

BRs, Bernie

If someone here helped You fix -or better, understand- your issue, hit the thanks icon @ bottom right corner, it's free and makes us feel helpy ;-)

Thanks for the pinout I've been looking all over for it ? I have found oem sensor on fleabay so have ordered and will make sure its not the one I've fitted playing up ?

11thevans said:

Thanks for the pinout I've been looking all over for it ? I have found oem sensor on fleabay so have ordered and will make sure its not the one I've fitted playing up ?

Click to expand...

Great, in the meantime do the checks previously posted .
you may have broken wire/ wires and the checks are designed to help.

If on o2 sensor you removed it has two white wires,white is usually heater wires, measure resistance on those wires and post result.

A sensible check is for battery +ve feed at the o2 sensor plug on one of the heater wires with ignition on, checking fuse for heater and relay for heater working.

From the battery positive to heater pin on o2 connector? Sorry I'm just double checking don't want to blow anything up ?