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Not sure if this counts as electric or oil. I figure there'll be both involved so i posted it here. This links on from my original post about the non exsistant fuel filter and my reason behind wanting to change it and also the chat about cleaning the injectors.

Got myself a cheapo elm327 obd reader and i have the following codes.

p0135 - Rave says Upstream heater LH bank - Short circuit or open circuit
p0155 - Rave says Upstream heater RH bank - Short circuit or open circuit
p0154 - Rave says Upstream sensor RH bank - electrical Open circuit
p1319 - Rave says Misfire detected with low fuel level

What's the score here then?

Lambda sensors? or a misfire that's causing the sensor(s) to not function correctly?

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A bit more info that most likely relates to this.

Was talking to GilbertD about a rough idle. I said i'd chucked some injector cleaner in there but it hadn't seem to help. Thats when i got on with thinking about getting in there and cleaning them.

Yesterday, i started it up and it immidiately revved to 2000rpm and climed slowly to about 2500rpm. Eventually settled down and i took the Mrs to McDonalds for her hangover burger pick me up.

When i got home, i googled the problem and since i still have the other p38 (which i know works fine), i was able to go parts robbing. I first changed the IAC valve. Started the car but didn't recreate the issue. Probably since it was warm. I figured while i was there, why not swap the MAF too and be done with it. I thought the idle was much better.

Today i started her up and she ticked over nicely. Went about 1 mile up to the shop and by the time i got there, the idle was rough. Also Noticeable when your just coming to a stop, it's as though your about to stall a manual car. Then it settle down once you're at a complete stop. Once you're on Gas it's about 80% improved but still not right.

I have no issues once we're moving. Gear changes all good. No pops or stutters.

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Clear the codes (if the elm327 can clear them or can it only read them?) and see if they return. If you can view live data, see what the lambda sensors are doing, are they stuck at 0 or 1V or are they flip flopping between the two? Can you read the long and short term fuel trims? What are they showing? To start I'd ignore the heater errors as a lambda sensor will work without heaters, it just takes a bit longer to give an output. The open circuit fault on bank 2 would give no output from that sensor which the ECU would see as 0V, or a lean mixture. The trims would then go fully rich to compensate but if the sensor isn't doing anything, it will still think it's lean and richen it up further still so you end up with one bank drowning in fuel.

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i cleared the codes on Friday. Got a couple of the codes back Saturday and today we've got the ensemble encore. I didn't want to post about it until i was sure the codes were right.

Can you or anyone recommend an app that will give me the data you've requested or should i just get torque pro? I got torque lite to begin with just to see what was going on.

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Not sure Torque Pro can do live data from what I've been able to find on it. But for under 3 quid it might be worth a go.

I use the Nano on the P38 but for everything else I use one of these http://www.ebay.co.uk/itm/Creader-6-VI-Car-Engine-Fault-Diagnostic-Scanner-Code-Reader-OBD2-obd-Scan-Tool-/112128720181 as it can show live data as a graph rather than changing numbers (which is better than the Nano in that respect). Set it to display long term trims and lambda outputs and you can easily see if one bank is switching while the other is flatlining. Until I got the Nano I used to use it on the P38 too. I only bought it to replace one of these http://www.ebay.co.uk/itm/U581-Car-Diagnostic-Scanner-CAN-OBD2-EOBD-Scan-Tool-Engine-Fault-Code-Reader-UK-/222440809157 purely because the Creader can do Japanese OBD and my daughter bought a Jap import MR2 Roadster and it wouldn't work.

If Torque won't do it, I might be persuaded to bung the U581 in a Jiffy bag for you to borrow if you ask very nicely.

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Right, lets see how we get on with this then.

I've set up torque. I've got displays as follows

O2 Volts bank 1 sensor 1
O2 Volts bank 1 sensor 2
O2 Volts bank 2 sensor 1
O2 Volts bank 2 sensor 2

Fuel Trim short term

Fuel Trim bank 1 sensor 1
Fuel Trim bank 1 sensor 2
Fuel Trim bank 2 sensor 1
Fuel Trim bank 2 sensor 2

Is that correct?

Thanks for your help GilbertD :-)

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Forget references to sensor 2, only US spec cars had post cat sensors, so you are only interested in sensor 1 on each bank. Short term trims will tell you what the fuelling is doing at any particular time. That won't have much affect on the running but if the short term trims are always going one way, the long term will slowly drift away to try to get the short terms back in range. So long term will tell you more that short term if Torque has that option.

Fuel trims are one of those things that confuse a lot of people but are actually simple when you get your head around it. The ECU has a pre-programmed map that adjusts the fuelling depending on load, throttle position, airflow, air and fuel temperature, etc. It adjusts by altering the length of the open time of the petrol injector (as fuel pressure is regulated and the injector has a hole of a set size) which alters the amount of fuel going in. The lambda sensors act as a final check that it has got it right. With manufacturing tolerances and wear in components, the amount of fuel for a set pulse length may be slightly out so the short term trims fine tune the pulse length a bit one way or the other to keep things correct. But, short term trims only have a limited amount of adjustment so if, for example, your fuel pressure is a bit low, then the short term trims will always be going positive to shove a bit more fuel in. If the short term trims are always one way or the other, the long term trims will adjust so that the short term are always hovering around the centre point.

So, if you have a duff lambda sensor, the ECU will see the output from that as showing a lean mixture. Short term trims will always be going positive to shovel more fuel in to correct it. As the output from the sensor doesn't change, it will still keep going positive so the long term will alter to try to get the short term central again but it never does so more and more fuel is chucked in until the car starts to run like a dog as it is being fed far more fuel than it needs. Extra fuel when cold isn't noticeable as extra fuel is needed when cold anyway, but once it warms up it will be like leaving the choke on when it doesn't need it.

As the LPG system slaves off the petrol ECU, then that will suffer too.

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yes, i would liken it to having the choke on the car at times. I've got mobizen rigged up with android on my laptop. I'll go for a spin and record the torque app. Then i can play the video back and see what's happening.

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right. made me a little video of what's happening.

fuel trim bank 2 sensor 1 doesn't read any data.
02 volts bank 2 sensor 1 doesn't move either. Constantly reads 0.4v

bank 1 sensors move all over the shop, as does the short term fuel trim.

does that translate into English meaning a new o2 sensor on bank 2 is required?

Bank 2 is drivers side yes?

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Yes, but before spending the money you can confirm a sensor problem by swapping them from side to side. If the one not giving any readings moves to the other side, you know it's the sensor. Bank 2 is right hand bank as seen from the drivers seat, so yes, drivers side.

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Gilbertd wrote:

Yes, but before spending the money you can confirm a sensor problem by swapping them from side to side. If the one not giving any readings moves to the other side, you know it's the sensor. Bank 2 is right hand bank as seen from the drivers seat, so yes, drivers side.

Champion. I've read they can be a pain to get out? Sensor located just before cat under car yes?

Thanks alot (again!) and we shall have neutral soon.

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I've never had a problem getting one out but I know others have. With a new sensor you should get a small sachet of lube to put on the threads so it doesn't seize in but if someone has changed it in the past and didn't use it then you might have problems. You can buy a special socket for them or if you don't have one and are at risk of rounding the hex, use a pair of Stillsons that tighten up the more grunt you give them.

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blueplasticsoulman wrote:

A bit more info that most likely relates to this.

Was talking to GilbertD about a rough idle. I said i'd chucked some injector cleaner in there but it hadn't seem to help. Thats when i got on with thinking about getting in there and cleaning them.

Yesterday, i started it up and it immidiately revved to 2000rpm and climed slowly to about 2500rpm. Eventually settled down and i took the Mrs to McDonalds for her hangover burger pick me up.

When i got home, i googled the problem and since i still have the other p38 (which i know works fine), i was able to go parts robbing. I first changed the IAC valve. Started the car but didn't recreate the issue. Probably since it was warm. I figured while i was there, why not swap the MAF too and be done with it. I thought the idle was much better.

Today i started her up and she ticked over nicely. Went about 1 mile up to the shop and by the time i got there, the idle was rough. Also Noticeable when your just coming to a stop, it's as though your about to stall a manual car. Then it settle down once you're at a complete stop. Once you're on Gas it's about 80% improved but still not right.

I have no issues once we're moving. Gear changes all good. No pops or stutters.

Have you checked that one of the cats is not blocked, if its when warm it means that the cats are getting to work and on gas it will flow slightly better, just a point I thought I would put accross as I have just done a de cat and a center box delete and she does seem to run alot better on petrol at least !

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dazer2000 wrote:

blueplasticsoulman wrote:

A bit more info that most likely relates to this.

Was talking to GilbertD about a rough idle. I said i'd chucked some injector cleaner in there but it hadn't seem to help. Thats when i got on with thinking about getting in there and cleaning them.

Yesterday, i started it up and it immidiately revved to 2000rpm and climed slowly to about 2500rpm. Eventually settled down and i took the Mrs to McDonalds for her hangover burger pick me up.

When i got home, i googled the problem and since i still have the other p38 (which i know works fine), i was able to go parts robbing. I first changed the IAC valve. Started the car but didn't recreate the issue. Probably since it was warm. I figured while i was there, why not swap the MAF too and be done with it. I thought the idle was much better.

Today i started her up and she ticked over nicely. Went about 1 mile up to the shop and by the time i got there, the idle was rough. Also Noticeable when your just coming to a stop, it's as though your about to stall a manual car. Then it settle down once you're at a complete stop. Once you're on Gas it's about 80% improved but still not right.

I have no issues once we're moving. Gear changes all good. No pops or stutters.

Have you checked that one of the cats is not blocked, if its when warm it means that the cats are getting to work and on gas it will flow slightly better, just a point I thought I would put accross as I have just done a de cat and a center box delete and she does seem to run alot better on petrol at least !

I haven't done this. However, data shows that there's nothing going on with bank 2 and the sensor is before the cat isn't it?

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both heaters are faulty anyway, so just feed it two new sensors and save the messing about!

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Both heaters faulty could be a manky supply connection to the ECU.

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One of my O2s was tightened by a gorilla and needed Marty hanging off the bottom of the car for several minutes before it shifted. I'd already wimped out after slipping the spanner off it a couple of times - I didn't want to round it.

The other one popped off just fine.

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A mate of mine had codes come up on his Focus for multiple lambda sensors and it turned out to be a blown fuse, after replacing the sensors and finding the faults still present.

Checked the wiring/power supply?

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Good point, as it's showing heater faults on both sensors. They are both powered from fuse 28 in the engine bay fuse box. Although even if it was a heater circuit failure, there would still be a reading from the sensor once the exhaust had warmed it up which is why I suggested swapping them over to make sure the fault swaps banks.

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Changed o2 sensor.

Still same.

Bank 1 - moves in both o2 voltage and Fuel trims.

Bank 2 - O2 volts read 0.0 and fuel trim doesn't shift from 0.0 neither.

What's my next move?