P0170 fuel trim bank 1

Bill Mac · 6th May 2016, 11:18

I have been looking on the forum for any resolution to this quite common problem and don't seem to see any real fix. Most of the information is disjointed.

I have Rover 75 tourer 1.8 operating on petrol and LPG.

Have had head gasket done and initially no problems for the first four weeks. The car started to lose power and felt as it was stuttering slightly when below the 2000 rpm range. Not all the time. EML light on then went off for about a week.

New ignition coils put on.
New upstream lambda/02 sensor replaced.
Air filter replaced.
MAP taken off and cleaned.

Since doing this the car is certainly more responsive but the fault is still the same and EML light still on. Is the next step to look at the IAC valve? or possibly reduce spark plug gap.

Any help from fellow sufferers would be grateful.

fandango151 · 6th May 2016, 12:03

Quote:

Originally Posted by Bill Mac

I have been looking on the forum for any resolution to this quite common problem and don't seem to see any real fix. Most of the information is disjointed.

I have Rover 75 tourer 1.8 operating on petrol and LPG.

Have had head gasket done and initially no problems for the first four weeks. The car started to lose power and felt as it was stuttering slightly when below the 2000 rpm range. Not all the time. EML light on then went off for about a week.

New ignition coils put on.
New upstream lambda/02 sensor replaced.
Air filter replaced.
MAP taken off and cleaned.

Since doing this the car is certainly more responsive but the fault is still the same and EML light still on. Is the next step to look at the IAC valve? or possibly reduce spark plug gap.

Any help from fellow sufferers would be grateful.

LPG is a fudge of petrol injection times. Run it on petrol onl and see if code returns once you have cleared it and if you have the ability ... Reset fuel adaptations. If the light stays off and you are running fine... It's the gas system.

To find the faults then you'll need to work out exactly what system you have, buy the cable and software then do some learning. My v6 threw a running too rich code, injectors were worn so replaced and retuned then we were away. That was until the vaporiser died, so replaced and we are off again.

Parts are generally fairly cheap in the grad scheme.

Edit: if anybody tells you this is normal behaviour on LPG is a liar. Running correctly there will be no eml issues.

xsport · 6th May 2016, 21:09

totaly agree fandango.about time this was made abundantly clear ! especially to those who dont understand what lpg is all about. im so glad you have said this.the easy part is the fitting of an lpg system and the hardest part is tune up and regular monitoring of the system so as not to pollute or indeed damage your engine. a correctly installed and tuned system should not throw eml.took me 6 mths to master this with software i bought but its well worth it. also dont be fooled by people who decat and remove o2 sensor function as they are polluting big time.contrary to what people think your mot tester should look on his system,type in your vin number and up will come the emmision tolerances that he has to work within.if he then chooses lpg as the fuel source the machine will apply a negative multiplier to arrive at your emmision levels / to pass or fail.this is done automaticaly by the machine.all cars that were originally fitted with o2 sensors have to be tested this way by mot laws.it is only vehicles that were not fitted with o2 sensors pre obd that have a smoke test only mot.the rules state that ALL spark ignition engines are tested this way.any tester that does not do this wants reporting.its not fair on others who have to follow the letter of the law and indeed polution deliberately is very wrong . so if you do the job please do it right for your sakes and that of others. thanks again fandango... YOUR SO RIGHT ..

Bill Mac · 9th May 2016, 09:22

Thanks very much guys for your responses. Update to you both. After cleaning MAP sensor with proper cleaner and replacing the upstream O2 sensor the EML stayed on. The car was sitting on my driveway when I completed the work.

I thought I would give it a short test drive to put the engine through the gears and one full driving cycle. While driving light went off and no fault code showed on reader. Since then the car is a much happier wee girl and at time of posting this is running fine.

However I will take your advice further and next month book it in for a LPG check. Thanks guys.

rich17865 · 9th May 2016, 10:12

Your LPG kit is running rich or lean and the car's ECU can no longer correct it enough, that is what brings that fault code on.

fandango151 · 9th May 2016, 10:16

Quote:

Originally Posted by Bill Mac

Thanks very much guys for your responses. Update to you both. After cleaning MAP sensor with proper cleaner and replacing the upstream O2 sensor the EML stayed on. The car was sitting on my driveway when I completed the work.

I thought I would give it a short test drive to put the engine through the gears and one full driving cycle. While driving light went off and no fault code showed on reader. Since then the car is a much happier wee girl and at time of posting this is running fine.

However I will take your advice further and next month book it in for a LPG check. Thanks guys.

Just beware who you take it to. There are many systems and you need the right cables/software for the right ones. Always best to find out exactly what you have before you chose the fitter. Some fit italian, some fit polish and whilst they do the same job you have to have the right kit else you can end up in a mess.

It does sound like you may have a problem unrelated to LPG if cleaning sensors fixed it. Really as above needs a run on petrol to see what giving you the problem before spending cash.

xsport · 9th May 2016, 22:04

before you go to get the car remapped,which is what he will do .. you need to run the car for 2 to three weeks on petrol only. although the light may be off the car still needs time for the fueling adaptations to fully adapt.this must cover all temp ranges and situations of idle/cruise and hard acceleration and warm up senarios. dont use lpg at all as the fuel trims on gas will start to move away from the petrol trims. a good lpg tune is a compromise at best between petrol and gas as the cars ecu mapping is and has all adaptations written in for petrol. so once you have done this then the car is ready at least for gas mapping.he will try to follow the petrol injector opening times for petrol as best he can to acheive this.this will include live mapping whilst driving under load and hard acceleration times and other senarios.once he has achieved this it will come under lambda control hopefully and the cars ecu will do the rest to keep it in check. the software can be downloaded free on the net and if you buy a lead (cheap to buy ) to connect to your lpg ecu and a laptop you can do this yourself , and save a lot of money .this is the way forward if you want to keep lpg.its not that daunting once you wrap your head around it its just a bit confusing for a start ... but thats the way of most technologies these days. wish you all the best.

Bill Mac · 16th May 2016, 14:45

I have a zavoli lpg system, do I just run it till the gas is finished and then continue to run on petrol only for a few weeks. I don,t have a manual switch over, the car automatically switches to LPG. I have never let it run out of gas before.

xsport · 16th May 2016, 23:48

Quote:

Originally Posted by Bill Mac

I have a zavoli lpg system, do I just run it till the gas is finished and then continue to run on petrol only for a few weeks. I don,t have a manual switch over, the car automatically switches to LPG. I have never let it run out of gas before.

you dont say how old the system is but if its fairly modern you should have an indicator light /gas operation switch on the dash. this should flash continuously whilst its on petrol.once warmed up and changed over automatically to gas by the system the light should stay illuminated. next time you start the car and the light flashes repeatedly just press the button once and this will abort the gas operation that follows. it will stay at this setting every time you drive until you set it back to petrol/gas auto change over again by pressing the button once. i hope you can follow what i mean. try this out next time you start her up.

6th May 2016, 11:18	#1
Bill Mac Newbie Rover 75 Tourer Join Date: Jan 2016 Location: Glasgow Posts: 12 Thanks: 4 Thanked 1 Time in 1 Post	P0170 fuel trim bank 1 I have been looking on the forum for any resolution to this quite common problem and don't seem to see any real fix. Most of the information is disjointed. I have Rover 75 tourer 1.8 operating on petrol and LPG. Have had head gasket done and initially no problems for the first four weeks. The car started to lose power and felt as it was stuttering slightly when below the 2000 rpm range. Not all the time. EML light on then went off for about a week. New ignition coils put on. New upstream lambda/02 sensor replaced. Air filter replaced. MAP taken off and cleaned. Since doing this the car is certainly more responsive but the fault is still the same and EML light still on. Is the next step to look at the IAC valve? or possibly reduce spark plug gap. Any help from fellow sufferers would be grateful.

6th May 2016, 21:09	#3
xsport Posted a thing or two rover 75 club se Join Date: Apr 2011 Location: Leicester Posts: 1,639 Thanks: 358 Thanked 419 Times in 310 Posts	lpg totaly agree fandango.about time this was made abundantly clear ! especially to those who dont understand what lpg is all about. im so glad you have said this.the easy part is the fitting of an lpg system and the hardest part is tune up and regular monitoring of the system so as not to pollute or indeed damage your engine. a correctly installed and tuned system should not throw eml.took me 6 mths to master this with software i bought but its well worth it. also dont be fooled by people who decat and remove o2 sensor function as they are polluting big time.contrary to what people think your mot tester should look on his system,type in your vin number and up will come the emmision tolerances that he has to work within.if he then chooses lpg as the fuel source the machine will apply a negative multiplier to arrive at your emmision levels / to pass or fail.this is done automaticaly by the machine.all cars that were originally fitted with o2 sensors have to be tested this way by mot laws.it is only vehicles that were not fitted with o2 sensors pre obd that have a smoke test only mot.the rules state that ALL spark ignition engines are tested this way.any tester that does not do this wants reporting.its not fair on others who have to follow the letter of the law and indeed polution deliberately is very wrong . so if you do the job please do it right for your sakes and that of others. thanks again fandango... YOUR SO RIGHT ..

9th May 2016, 22:04	#7
xsport Posted a thing or two rover 75 club se Join Date: Apr 2011 Location: Leicester Posts: 1,639 Thanks: 358 Thanked 419 Times in 310 Posts	lpg before you go to get the car remapped,which is what he will do .. you need to run the car for 2 to three weeks on petrol only. although the light may be off the car still needs time for the fueling adaptations to fully adapt.this must cover all temp ranges and situations of idle/cruise and hard acceleration and warm up senarios. dont use lpg at all as the fuel trims on gas will start to move away from the petrol trims. a good lpg tune is a compromise at best between petrol and gas as the cars ecu mapping is and has all adaptations written in for petrol. so once you have done this then the car is ready at least for gas mapping.he will try to follow the petrol injector opening times for petrol as best he can to acheive this.this will include live mapping whilst driving under load and hard acceleration times and other senarios.once he has achieved this it will come under lambda control hopefully and the cars ecu will do the rest to keep it in check. the software can be downloaded free on the net and if you buy a lead (cheap to buy ) to connect to your lpg ecu and a laptop you can do this yourself , and save a lot of money .this is the way forward if you want to keep lpg.its not that daunting once you wrap your head around it its just a bit confusing for a start ... but thats the way of most technologies these days. wish you all the best.

9th May 2016, 09:22	#4
Bill Mac Newbie Rover 75 Tourer Join Date: Jan 2016 Location: Glasgow Posts: 12 Thanks: 4 Thanked 1 Time in 1 Post	Thanks very much guys for your responses. Update to you both. After cleaning MAP sensor with proper cleaner and replacing the upstream O2 sensor the EML stayed on. The car was sitting on my driveway when I completed the work. I thought I would give it a short test drive to put the engine through the gears and one full driving cycle. While driving light went off and no fault code showed on reader. Since then the car is a much happier wee girl and at time of posting this is running fine. However I will take your advice further and next month book it in for a LPG check. Thanks guys.

9th May 2016, 10:12	#5
rich17865 This is my second home Transit Connect Join Date: Feb 2011 Location: Crewe Posts: 9,532 Thanks: 868 Thanked 1,619 Times in 1,095 Posts	Your LPG kit is running rich or lean and the car's ECU can no longer correct it enough, that is what brings that fault code on.

16th May 2016, 14:45	#8
Bill Mac Newbie Rover 75 Tourer Join Date: Jan 2016 Location: Glasgow Posts: 12 Thanks: 4 Thanked 1 Time in 1 Post	I have a zavoli lpg system, do I just run it till the gas is finished and then continue to run on petrol only for a few weeks. I don,t have a manual switch over, the car automatically switches to LPG. I have never let it run out of gas before.