Help interpret my adaptives
Discussion
Gents,
I need your help, originally I thought I had a knackered lambda on the even bank. However from the looks of these adaptives both banks look to be running very rich this could explain the significant popping and banging at slow speeds.
I know I need to balance the throttles but the lamda readings are fluctuating massively almost in a close loop of increase, then decrease in fueling.
Thanks for your help
I need your help, originally I thought I had a knackered lambda on the even bank. However from the looks of these adaptives both banks look to be running very rich this could explain the significant popping and banging at slow speeds.
I know I need to balance the throttles but the lamda readings are fluctuating massively almost in a close loop of increase, then decrease in fueling.
Thanks for your help
I'm no expert but I cant see anything drastically wrong, the lamda's only work at part throttle lowish RPM, and switch between 0 and 1 which yours are doing and both banks are attempting to be trimmed to obtain the ideal mixture. What are you expecting to see?.
By all means set up the throttle pots reset the adaptives and try again. I would also check carefully any play in the linkage,and TPS. Check the tracking of both pots across the full travel then check again as they return back to their stops it should match evenly to within 1 or 2% .
If all is OK then I would look at Plugs, HT leads and coil packs if the backfire persists.
JUST TO CONCLUDE I AM NO EXPERT BUT NONE THE LESS I HOPE THIS HELPS.
By all means set up the throttle pots reset the adaptives and try again. I would also check carefully any play in the linkage,and TPS. Check the tracking of both pots across the full travel then check again as they return back to their stops it should match evenly to within 1 or 2% .
If all is OK then I would look at Plugs, HT leads and coil packs if the backfire persists.
JUST TO CONCLUDE I AM NO EXPERT BUT NONE THE LESS I HOPE THIS HELPS.
right update . . . .
Changed the ball joints on the linkage to rod ends to reduce the slack and have balanced both throttles, well as much as you can over the range with an error between 0 and 1%.
I also noticed that tpot one has noise of c0.7%, is this worth changing?
The problems are that when cold the idle is so low that if you don't use the throttle the engine just dies completely but when up to temp it idles at 1050rpm. This is with both throttles adjusted to 16.9%.
Could this be related to resetting the adaptives i.e. not giving the ECU enough time to make adjustments? How long roughly should this take?
Would anybody without running issues be willing to post up their adaptives?
Parts changed:
Plugs + full service
throttle cable
HT leads
As always thanks for all your help
Changed the ball joints on the linkage to rod ends to reduce the slack and have balanced both throttles, well as much as you can over the range with an error between 0 and 1%.
I also noticed that tpot one has noise of c0.7%, is this worth changing?
The problems are that when cold the idle is so low that if you don't use the throttle the engine just dies completely but when up to temp it idles at 1050rpm. This is with both throttles adjusted to 16.9%.
Could this be related to resetting the adaptives i.e. not giving the ECU enough time to make adjustments? How long roughly should this take?
Would anybody without running issues be willing to post up their adaptives?
Parts changed:
Plugs + full service
throttle cable
HT leads
As always thanks for all your help
Edited by e12mat on Sunday 15th April 09:38
One throttle pot always seems to be noisy for some unaccountable reason. At least it is on all the cars I have looked at. I wouldn't bother to change the pot so long as it is varying smoothly.
What are the air flows like on each bank at idle? When you work through the setup procedure, you should set the idle last, while the engine is hot. Do you mean that your hot idle is changing once you have done this?
What are the air flows like on each bank at idle? When you work through the setup procedure, you should set the idle last, while the engine is hot. Do you mean that your hot idle is changing once you have done this?
The throttle pots also seem to change in resistance terms as they warm up.
I thought I would be a able to borrow an air syncrometer from a friends garage but they seem to be few and far between these days. Is there one you could recommend that is Cerb friendly?
adjusted the throttles again and despite the idle the addaptives are definately looking better. The majority of sites are now much less than 10.
What should I in theory be aiming for between -2 and +2?
One of these will do fine http://www.ebay.co.uk/itm/CARBURETTOR-SYNCHROMETER...
There is no point whatsoever in setting the throttle pots without balancing the air flow. All the pots do is tell the ECU how far the throttle spindles have been turned. If the air flow isn't balanced between banks when you set the pots, then you do not have a known starting point and the ECU is getting misinformation and therefore will not fuel correctly.
If one bank is flowing more than the other and you set the throttle pots to the same reading then you are making the situation worse not better. You need to follow the setup procedure in the manual precisely. Measuring the air flow is not optional.
There is no point whatsoever in setting the throttle pots without balancing the air flow. All the pots do is tell the ECU how far the throttle spindles have been turned. If the air flow isn't balanced between banks when you set the pots, then you do not have a known starting point and the ECU is getting misinformation and therefore will not fuel correctly.
If one bank is flowing more than the other and you set the throttle pots to the same reading then you are making the situation worse not better. You need to follow the setup procedure in the manual precisely. Measuring the air flow is not optional.
Edited by Tanguero on Tuesday 17th April 09:03
Tanguero said:
One of these will do fine http://www.ebay.co.uk/itm/CARBURETTOR-SYNCHROMETER...
There is no point whatsoever in setting the throttle pots without balancing the air flow. All the pots do is tell the ECU how far the throttle spindles have been turned. If the air flow isn't balanced between banks when you set the pots, then you do not have a known starting point and the ECU is getting misinformation and therefore will not fuel correctly.
If one bank is flowing more than the other and you set the throttle pots to the same reading then you are making the situation worse not better. You need to follow the setup procedure in the manual precisely. Measuring the air flow is not optional.
Yes it is. There is no point whatsoever in setting the throttle pots without balancing the air flow. All the pots do is tell the ECU how far the throttle spindles have been turned. If the air flow isn't balanced between banks when you set the pots, then you do not have a known starting point and the ECU is getting misinformation and therefore will not fuel correctly.
If one bank is flowing more than the other and you set the throttle pots to the same reading then you are making the situation worse not better. You need to follow the setup procedure in the manual precisely. Measuring the air flow is not optional.
Edited by Tanguero on Tuesday 17th April 09:03
If you have balanced throttle readings and equal adaptives then you have equal airflow.
A syncro will give you a closer guess to the airflow but you can balance the banks with the adaptive readings if you don't have access to one.
Both Ridds and Tanguero make valid points. I would like to add that you need to check that you dont have worn spindles or badly adjusted butterflys. The easiest way is to listen to the hiss with a length of hose positioned very close on each inlet if one is way louder on a bank then it may be where your problem lies. The quality of the engineering is poor on both the 4.5 and 4.2 inlets. I scrapped a set of 4.2 inlets because no matter how hard I tried I could not get a reliable tickover.
ridds said:
Yes it is.
If you have balanced throttle readings and equal adaptives then you have equal airflow.
A syncro will give you a closer guess to the airflow but you can balance the banks with the adaptive readings if you don't have access to one.
I beg to differ! If it were possible to balance the whole of both adaptive maps for all points then yes I concede that would come close, however it is practically impossible to do that accurately. Besides the adaptive is a secondary measurement calculated based on the lambda output against fueling so if there is any question as to the lambda sensor function then it isn't reliable. Air flow is a primary measurement so is inherently more accurate and should be used. If you have balanced throttle readings and equal adaptives then you have equal airflow.
A syncro will give you a closer guess to the airflow but you can balance the banks with the adaptive readings if you don't have access to one.
Tanguero said:
ridds said:
Yes it is.
If you have balanced throttle readings and equal adaptives then you have equal airflow.
A syncro will give you a closer guess to the airflow but you can balance the banks with the adaptive readings if you don't have access to one.
I beg to differ! If it were possible to balance the whole of both adaptive maps for all points then yes I concede that would come close, however it is practically impossible to do that accurately. Besides the adaptive is a secondary measurement calculated based on the lambda output against fueling so if there is any question as to the lambda sensor function then it isn't reliable. Air flow is a primary measurement so is inherently more accurate and should be used. If you have balanced throttle readings and equal adaptives then you have equal airflow.
A syncro will give you a closer guess to the airflow but you can balance the banks with the adaptive readings if you don't have access to one.
They relationship between blade angle and the quantity of fuel required for the blade angle is then "checked" by the adaptive compensation. If you have equal throttle pot values with very low or zero adaptives then you "do" have equal airflow as far as the EMS is concerned and at the end of the day all you want to get right is the AFR at that speed and load point. If one bank is working slightly more than the other it makes no odds to the ECU (however this is being checked by confirming the blade and adaptive values are equal). It will only ever fuel according to engine speed and throttle blade angle.
Also if there is question to your Lambda function then it't not going to work properly anyway as this is the loopback function. So having the airflow balanced and throttle readings equal would then be thrown out but the returned value from the Lambda sensor.
ridds said:
Which part of the EMS uses airflow though? It doesn't and therefore it's not critical. Providing you have a throttle blades that are both perpendicular to the ports at WOT and also close correctly then they are as close as you need to get them.
As airflow is proportional to the throttle angle and hence the throttle pot value, the way I see it is that the ECU uses the throttle angle to measuring air flow, so I don't think you can say that the ECU isn't using airflow. ridds said:
They relationship between blade angle and the quantity of fuel required for the blade angle is then "checked" by the adaptive compensation. If you have equal throttle pot values with very low or zero adaptives then you "do" have equal airflow as far as the EMS is concerned and at the end of the day all you want to get right is the AFR at that speed and load point. If one bank is working slightly more than the other it makes no odds to the ECU (however this is being checked by confirming the blade and adaptive values are equal). It will only ever fuel according to engine speed and throttle blade angle.
Also if there is question to your Lambda function then it't not going to work properly anyway as this is the loopback function. So having the airflow balanced and throttle readings equal would then be thrown out but the returned value from the Lambda sensor.
My understanding it is that the combination of throttle angle and RPM is used to select a fuel amount from a table (which is appropriate to the amount of air flowing at that throttle opening). In closed loop running the lambda sensor output is then used as feedback to adapt that fuel amount to a close to ideal mixture. So thinking about it, I take your point that if there is no adaptation required on either bank then the flow must be the same regardless of throttle pot settings for a given fuel map site.Also if there is question to your Lambda function then it't not going to work properly anyway as this is the loopback function. So having the airflow balanced and throttle readings equal would then be thrown out but the returned value from the Lambda sensor.
My experience of setting the car up both ways, however, is that measuring the airflow independently with a meter and setting the link rod based on equal air flow gives far better results, probably because I find it is easier (and you can jimmy it to account for any play in the linkage).
Tanguero said:
ridds said:
Which part of the EMS uses airflow though? It doesn't and therefore it's not critical. Providing you have a throttle blades that are both perpendicular to the ports at WOT and also close correctly then they are as close as you need to get them.
As airflow is proportional to the throttle angle and hence the throttle pot value, the way I see it is that the ECU uses the throttle angle to measuring air flow, so I don't think you can say that the ECU isn't using airflow. ridds said:
They relationship between blade angle and the quantity of fuel required for the blade angle is then "checked" by the adaptive compensation. If you have equal throttle pot values with very low or zero adaptives then you "do" have equal airflow as far as the EMS is concerned and at the end of the day all you want to get right is the AFR at that speed and load point. If one bank is working slightly more than the other it makes no odds to the ECU (however this is being checked by confirming the blade and adaptive values are equal). It will only ever fuel according to engine speed and throttle blade angle.
Also if there is question to your Lambda function then it't not going to work properly anyway as this is the loopback function. So having the airflow balanced and throttle readings equal would then be thrown out but the returned value from the Lambda sensor.
My understanding it is that the combination of throttle angle and RPM is used to select a fuel amount from a table (which is appropriate to the amount of air flowing at that throttle opening). In closed loop running the lambda sensor output is then used as feedback to adapt that fuel amount to a close to ideal mixture. So thinking about it, I take your point that if there is no adaptation required on either bank then the flow must be the same regardless of throttle pot settings for a given fuel map site.Also if there is question to your Lambda function then it't not going to work properly anyway as this is the loopback function. So having the airflow balanced and throttle readings equal would then be thrown out but the returned value from the Lambda sensor.
My experience of setting the car up both ways, however, is that measuring the airflow independently with a meter and setting the link rod based on equal air flow gives far better results, probably because I find it is easier (and you can jimmy it to account for any play in the linkage).
I agree that it is nice to just a good even balanced airflow using a sync to start you off. I was just showing that you can get just as good a result by interpreting the adaptives and tweaking accordingly.
What speeds do you measure the airflow at, just idle?
I measure the air flow (and do most of the setup) at the highest speed my meter can cope with. The logic being that part throttle is where it actualy matters rather than sitting at idle. By wedging the throttle linkage open at the point that the throttle cable connects rather than relying on the idle screw on the other bank, I find you can adjust out all the play in the linkage and just finally set the idle at the end of the process.
That said a carbon fibre rod and a couple of really good quality rose joints eliminate most of the slop and thermal expansion you get with the standard setup.
That said a carbon fibre rod and a couple of really good quality rose joints eliminate most of the slop and thermal expansion you get with the standard setup.
scotty_d said:
Tanguero said:
That said a carbon fibre rod and a couple of really good quality rose joints eliminate most of the slop and thermal expansion you get with the standard setup.
Does any one make these that we can buy off the shelf?Square section carbon tube off ebay, likewise a couple of high quality M5 rose joints and locknuts, one joint/nut left hand thread, one right hand and a short piece of square section steel (or brass) bar that just fits inside the carbon tube.
Drill and tap a short length of the bar for each end (one left hand and one right) then epoxy that into the carbon tube flush with the end. Screw the rose joints into the ends when the epoxy goes off and job is jobbed.
Total cost around £25 if I remember rightly. You cna probably do it even cheaper if you use round tube and rod for the inserts, but the square tube makes it nice and easy to turn when you adjust it.
Gassing Station | Cerbera | Top of Page | What's New | My Stuff