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WRXLink V3-4 Cut Issues

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I've been experiencing some form of cut in 3-5 gears in the last 3-4 months, and had just put it down to colder weather and some form of boost cut.

I did a log tonight where it hit the cut in third at WOT, and from what I can see on the log it is going over the MAP limit. 

I was wondering if someone can confirm what I am thinking, and that an overboost cut is what is occurring? 

I've coloured in the file where I believe it happened based on PCLink (7:01 min mark).

The Dropbox link has the files attached exported to Excel.

https://www.dropbox.com/sh/nzm145fkn5riqn5/AAC9azFLmFIA-uzDe8ukrBFza?dl=0

 

Log 2018-09-23 6;16;22 pm.llg

I think this is my current map if that helps.

EVO98 MAP.pclr

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Yep its reporting as MAP limit (and no other limits), and the 245kpa limit is very close to the 235kpa its logging, so with a bit of "it spiked up between log events" it all seems to line up.

Bumping that MAP limit up a bit will help you out a little bit (assuming you do actually want more boost), but notice you are also seeing about 4.3V on your MAP sensor voltage so it's almost maxed out. You might get another 30-40kpa before the sensor cant read any higher.

image.png.92a8a9e48225ffd9fa26da0faf78bd86.png

On the other hand if your problem is that you are happy with the boost level you have (1.4 bar is a fair bit on a factory engine) , you need to drop the numbers in your wastegate duty cycle table a little bit or set up closed loop boost control. It makes sense that if you are right on the edge of MAP limit in warm weather, that it creeps up a little bit under cold (dense air) conditions given you are running open loop boost control. 

On second look at your IAT wastegate trim however, where in your intake is your IAT sensor and what type of sensor is it? 20deg C is pretty low for any post turbo reading really, especially at 1.4bar, and it looks like it only moves 1 deg between 60 kpa and 240kpa. I was going to suggest putting a couple negative % WGDC trim in the IAT boost table at low temperatures to compensate but if its the factory temp sensor (pre turbo) you should really move/replace this first so you are working with accurate numbers.

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36 minutes ago, cj said:

Yep its reporting as MAP limit (and no other limits), and the 245kpa limit is very close to the 235kpa its logging, so with a bit of "it spiked up between log events" it all seems to line up.

Bumping that MAP limit up a bit will help you out a little bit (assuming you do actually want more boost), but notice you are also seeing about 4.3V on your MAP sensor voltage so it's almost maxed out. You might get another 30-40kpa before the sensor cant read any higher.

image.png.92a8a9e48225ffd9fa26da0faf78bd86.png

On the other hand if your problem is that you are happy with the boost level you have (1.4 bar is a fair bit on a factory engine) , you need to drop the numbers in your wastegate duty cycle table a little bit or set up closed loop boost control. It makes sense that if you are right on the edge of MAP limit in warm weather, that it creeps up a little bit under cold (dense air) conditions given you are running open loop boost control. 

On second look at your IAT wastegate trim however, where in your intake is your IAT sensor and what type of sensor is it? 20deg C is pretty low for any post turbo reading really, especially at 1.4bar, and it looks like it only moves 1 deg between 60 kpa and 240kpa. I was going to suggest putting a couple negative % WGDC trim in the IAT boost table at low temperatures to compensate but if its the factory temp sensor (pre turbo) you should really move/replace this first so you are working with accurate numbers.

HI,

thanks for the response!

I'm running a built 2.1 stroker motor, so the boost is ok :) Was aiming for higher, but my turbo is struggling for any more (during tuning). Could be time for a new MAP sensor and some increased limits? My car is running the original Subaru MAP sensor from 1998!

I've got the Link temperature sensor kit installed, but only 1 sensor is currently wired in, the other is just taped into the cooler. Its at the front left of the top mount intercooler (turbo side of engine). Do you think I should be using the other sensor that is installed on the opposite side at the back of the cooler?

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To fix it for today, bump up the MAP limit from 245 to say 260. Longer term if you want any substantial boost increase you will need to move to something like this http://www.nzefi.com/product/link-4-bar-map-sensor/ to get some head room in your MAP readings.

As far your IAT sensor, the general idea is the closer you can get it to the throttle blade the better, as you want it to show as close as possible to the temperature of the air entering the engine. Typically on subaru's with top mounts this means on the header tank on the engine side of the intercooler. Do you have a part number for the sensor you have? IAT sensors come in fast and slow versions, also referred to as open or closed element. open element sensors (aka fast response sensors) would typically register a 20-30* temperature change in a second or 2 and are what you ideally want in a turbo engine where temperatures vary by maybe 50 deg based on boost level. 

It sounds like your sensor is installed on the "hot" side of the intercooler, and so it should really be showing well into double digit temperature changes when on boost. I'm a bit suspicious that its not responding correctly. Try something like pointing a hair dryer into the piping just upstream from the sensor and see how quickly it responds and if it actually goes up by 30-40 deg to whatever temp your hand tells you the hair dryer is putting out.

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5 hours ago, cj said:

As far your IAT sensor, the general idea is the closer you can get it to the throttle blade the better, as you want it to show as close as possible to the temperature of the air entering the engine. Typically on subaru's with top mounts this means on the header tank on the engine side of the intercooler. Do you have a part number for the sensor you have? IAT sensors come in fast and slow versions, also referred to as open or closed element. open element sensors (aka fast response sensors) would typically register a 20-30* temperature change in a second or 2 and are what you ideally want in a turbo engine where temperatures vary by maybe 50 deg based on boost level. 

It sounds like your sensor is installed on the "hot" side of the intercooler, and so it should really be showing well into double digit temperature changes when on boost. I'm a bit suspicious that its not responding correctly. Try something like pointing a hair dryer into the piping just upstream from the sensor and see how quickly it responds and if it actually goes up by 30-40 deg to whatever temp your hand tells you the hair dryer is putting out.

I've got a Delphi style open element sensor. I did have a CEL recently (refer to the photo attached), but after clearing the code it hasn't returned. Is this related?

I didn't tune this car myself, so I'm only just figuring out how to log and read the info.

20180908_111807.jpg

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16 hours ago, cj said:

Yep its reporting as MAP limit (and no other limits), and the 245kpa limit is very close to the 235kpa its logging, so with a bit of "it spiked up between log events" it all seems to line up.

Just FYI, the MAP limit has a control range just like all the other limits, if advanced mode is turned off the default control range is 10Kpa, so with 245Kpa in the limit table, the ECU would start applying a small amount of cut at 235Kpa.

 

Our notes suggest the WRX1-6 MAP sensors are only rated to about 225KPa so this is running dangerously close to its upper limit.  Personally I would be lowing the boost a little rather than adjusting the MAP limit, at least until the MAP sensor is replaced. 

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An Volt2 is your old MAF sensor. This isnt used for anything calculation wise, and is likely just there to help tuning AVCS. It looks like it is also about at its limit with the air flow you've got going on - looking at that graph its peaking at 4.71 volts. Again it wouldnt be surprising if it crept above 4.95 at some point and tripped an error warning. Setting the anv2 error high value to 5v will disable this and is harmless as the MAF value isnt used anywhere. 

Are you 100% sure the IAT sensor in the factory MAF is not wired up? can you get a multimeter and verify that the anTemp3 pin on your ECU plug goes to one of the pins on your delphi sensor and not to pin 2 or 4 of the MAF (where the factory temp sensor is)?

 

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2 hours ago, Adamw said:

Just FYI, the MAP limit has a control range just like all the other limits, if advanced mode is turned off the default control range is 10Kpa, so with 245Kpa in the limit table, the ECU would start applying a small amount of cut at 235Kpa.

 

Our notes suggest the WRX1-6 MAP sensors are only rated to about 225KPa so this is running dangerously close to its upper limit.  Personally I would be lowing the boost a little rather than adjusting the MAP limit, at least until the MAP sensor is replaced. 

I'm going to look to upgrade my MAP sensor in the near future.

2 hours ago, cj said:

An Volt2 is your old MAF sensor. This isnt used for anything calculation wise, and is likely just there to help tuning AVCS. It looks like it is also about at its limit with the air flow you've got going on - looking at that graph its peaking at 4.71 volts. Again it wouldnt be surprising if it crept above 4.95 at some point and tripped an error warning. Setting the anv2 error high value to 5v will disable this and is harmless as the MAF value isnt used anywhere. 

Are you 100% sure the IAT sensor in the factory MAF is not wired up? can you get a multimeter and verify that the anTemp3 pin on your ECU plug goes to one of the pins on your delphi sensor and not to pin 2 or 4 of the MAF (where the factory temp sensor is)?

 

My current tune is still utilising the stock MAF until I can get a better MAP sensor and go solely with that. As my MAF is still running as per factory I assume its still wired up with the sensor, but I didn't complete the wiring work on the newer sensor within the top mount so I can't really confirm.

How can I change the MAP Limit for the time being?

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Change the values between about 70 and 100deg from 245kpa up to say 255 or 260.

image.png.0196e98b6e7c9063501c6d1d516e6283.png

To check the air temp wiring, unplug the sensor plug and the ECU plug and check for continuity with a multimeter. Your config file shows only ANTemp3 as an IAT sensor, which is pin8 on the expansion connector on a 3-4 WRXlink, so just put one end of the multimeter on this pin, and check if it has continuity to either pin of the temp sensor in the intercooler, or one of the pins in the AFM.

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I changed the values to 260kPa, and did some logging tonight and hit the 245kPa soft cut again. Is there something I must do once I change the values as noted above?

I haven't had a chance to check the MAF IAT situation yet.

MAF is definitely maxing out though, hitting 4.8V now.

 

Also, what could cause the chugging around 3:26min mark?

Tom

 

Log 2018-09-30 6;55;18 pm.llg

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Can you post your pclr file too? 

At 13:04 is the only point you hit MAP limit, and yes its still showing as 245 so i'd guess you've only adjusted it for certain ECT's. 

At a few other points (eg 12:36) your MAP appears to flatten out a bit at 230-ish but you arent hitting the limit - even if the limit event isnt in the log it would still have the -5 deg ingition trim active for a few seconds and we only see this at 13:04. At both these points you're at 100% TPS and the ECU is requesting 70.5% DC from the wastegate. This lines up with what you said earlier that some days its ok, and other days you get MAP limit behaviour. I'd say your tune (specifically the boost control settings) puts you very close to your MAP limit all the time (230kpa ish), and when something is a little bit different (air temp/atmospheric pressure, oil temp, heat in the metal of the turbo, maybe the gear you are in or the amount of weight in the car), it causes you to get 5 extra kpa and hit the limit.

At 3:26, and everywhere else you are at light throttle, you are running _very_ lean. Anywhere in the log where you are over ~50% throttle the lambda value is good, and at idle its ok as well (a bit rich but a reasonable value, and the richness might be needed depending on engine mods). It looks like the fuel table at light load hasnt been well tuned. In fact if you swap your originally posted map to graphical view you can see the big dip in fuel values between idle and about 110kpa. In the pic below you can see the valley right along the -40kpa load cells, and pretty much everywhere in the red square looks like it needs to get bumped up by 3 or 4 points.

image.png.84997783071b6f4233ea211e421870f1.png

image.png.d02b6dd6b2618a3a3c4a73b8be36c047.png

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your pclr file shows 260 MAP limit, but your log file shows that it was using a 245 limit when you captured that log. 

Did you remember to store the config to the ECU after you made the changes (press F4 or ECU controls>store to ECU)? If you dont do this, and just save the map to your laptop, the ECU itself will go back to the old config on poweroff/on.

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1 hour ago, cj said:

your pclr file shows 260 MAP limit, but your log file shows that it was using a 245 limit when you captured that log. 

Did you remember to store the config to the ECU after you made the changes (press F4 or ECU controls>store to ECU)? If you dont do this, and just save the map to your laptop, the ECU itself will go back to the old config on poweroff/on.

I didn't do the store config, had no idea :P

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