What AF gauge are you using ? Do you ad oil to your fuel mix? At idle warmed up you should see in around 14.2 at idle. How old is the sensor? Are you running a bung extender on the sensor?
Infamous det code on decel?
- Thread starter Octanee
- Start date
Good questions. I'd go replace the DET sensor, just for fun.
WFO AFR reasons should be 12.5.
Mid range should be 13.0-13.5
Idle an low throttle cruising should be 14.0-14.5.
Also, make sure the DET sensor wire isn't routed weird and that it's torqued correctly.
My buddy Joe has a 2012 with a BD turbo. He was having DET issues at upper mid range.
Boondockers told him to turn in a 1/4 turn it something and reroute it a certain way. Cut the DET issue into fractions.
When I've got DET issues on my big bore in mid range, it was happening in soft acceleration in upper mid range. When I let off who and feathered it right back in, I would hit DET. I used to think it was because I let off, but I learned it's when I touched the throttle going back in.
It came down to these items that we fixed. Problem solved:
Fuel filter change.
Injector and fuel line O rings.
Pipe rubbing/engine mounts.
DET sensor torque and wire route.
Accelerator pump seeing needed to richen on my Dobek programmer.
There could always be other things... but that's what MY issues were.
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Good info, the a/f gauge is a AEM Universal exhaust gas, no extension wires or such, I put it on last ~ spring, it may now have approx 700 km or so on it, I just haven't seen it behave that way before down the trails,
Det sensor wise, I don't think I had torque'd it on, I believe I gave er the ol snug in with a wrench which may be an issue perhaps, maybe I over torque'd it.
But you never know, It could be a det sensor not performing properly, or maybe I truly have an issue with my stock fuel injection system down the trail which *may* be causing det too. or could be the exhaust pipe
----- I got googling det sensor torque and I should know better being a auto tech lmao! but they are sensitive to torque'ing and over torque'ing will make them pick up more than intended and false readings. I think this is a solid item for me to check over. I also have a spare pro I could swap the DET sensors for the heck of it too.
I do appreciate the info on what solved yours! I'll swap out my fuel filter for a new one this week as well, sled has new engine mounts. I don't see anything else rubbing, det sensor wire routing is good. i did try turning up the accel pump function and it didnt help any.
Det sensor wise, I don't think I had torque'd it on, I believe I gave er the ol snug in with a wrench which may be an issue perhaps, maybe I over torque'd it.
But you never know, It could be a det sensor not performing properly, or maybe I truly have an issue with my stock fuel injection system down the trail which *may* be causing det too. or could be the exhaust pipe
----- I got googling det sensor torque and I should know better being a auto tech lmao! but they are sensitive to torque'ing and over torque'ing will make them pick up more than intended and false readings. I think this is a solid item for me to check over. I also have a spare pro I could swap the DET sensors for the heck of it too.I do appreciate the info on what solved yours! I'll swap out my fuel filter for a new one this week as well, sled has new engine mounts. I don't see anything else rubbing, det sensor wire routing is good. i did try turning up the accel pump function and it didnt help any.
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Good info, the a/f gauge is a AEM Universal exhaust gas, no extension wires or such, I put it on last ~ spring, it may now have approx 700 km or so on it, I just haven't seen it behave that way before down the trails,
Det sensor wise, I don't think I had torque'd it on, I believe I gave er the ol snug in with a wrench which may be an issue perhaps, maybe I over torque'd it.
But you never know, It could be a det sensor not performing properly, or maybe I truly have an issue with my stock fuel injection system down the trail which *may* be causing det too. or could be the exhaust pipe
I do appreciate the info on what solved yours! I'll swap out my fuel filter for a new one this week as well, sled has new engine mounts. I don't see anything else rubbing, det sensor wire routing is good. i did try turning up the accel pump function and it didnt help any.
A couple of things.
I asked you earlier if you had the rising rate fuel pressure regulator and you answered yes. The later Boost-it Pros and Axys no longer used the rising rate regulator.
You really want to update that. Its old school, it worked back in the day and most of the turbo guys tried it but it went away.
I think a lot of what you have going on is in the tune your running.
This is what I would do.
1 .Change O2 sensor (if your seeing 13.2 at idle its probably done)
2. Make sure nothing his rattling under the hood. (false det)
3 . Det sensor properly installed and torqued. ( personally I've had them in and out and not torqued and never had a problem).
4. Double check your Octane. Fresh fuel and double check your calculations. (Did it myself once, wrong measurements in the soup)
5. XIC box. If you want to update it?? NON Rising rate.
IN HIDDEN settings
INJ LAG 1
MIN RPM 42
Reg settings
Main 65
Threshold -8
5500 RPM -60
5750 -20
6000 -13
6250 -14
6500 -10
6750 -7
7000 -6
7250 -4
7500 -5
7750 -2
8000 +6
8250 +12
8500 +12
And so on at + 12
This is the tune for a NON rising rate fuel pressure regulator (Boost-its) numbers
Just pull the boost line from the regulator and cap it.
One more thing. In checking back thru notes. Boost -it liked to see 11.8 - 12.1 at WOT not 12.2 12.4 like I had written earlier. Memory isn't what it used to be.
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great info sled head!, I think I had received mixed info then from TJ@boost it, when I got the sled i noticed the Rising rate was NOT plumbed in, coming off my yamaha apex which is what the FPR is from and the vacuum line indeed connected of course I thought it was odd so I called him and he said "thats odd it should be plumbed in" So first thing I did was install a line to the FPR to make it rising rate,
now that I think about it as well, that could be some of my issues with tuning LOL! I ran higher boost yesterday, approx 7-8# and ran rich so I was tweaking it tons, then lower boost it was lean.... I didn't think of that one.
I'm going to replace my A/f sensor as I'm sure its toast so next weekend I'll have a new one as well.
fuel wise I never did an exact mix per say. the 2nd last ride I had mix'd it IIRC about 40% av, and it was just over half a tank, then before yesterdays ride I topped up the tank, it took 18L straight av gas in, so the previous mix's should of had it for sure 30% av then my 40%, so I guestimated a safe 60% av mix in the last ride, could be more like 70% realistically. again it made no difference from running 30% av and 94 octane or running 60% av and 94, the source of 94 octane chevron is known to be good by the locals with their street race cars and I ran it in my 310 hp yamaha apex straight @20# boost it never threw any det codes on it, had the head shim but never had an issue, from my experience its been a good fuel but that is a totally different machine and a 4 stroke.
The map that TJ had given me hasnt worked at all but again could of been due to the FPR having the line hooked up.
now that I think about it as well, that could be some of my issues with tuning LOL! I ran higher boost yesterday, approx 7-8# and ran rich so I was tweaking it tons, then lower boost it was lean.... I didn't think of that one.
I'm going to replace my A/f sensor as I'm sure its toast so next weekend I'll have a new one as well.
fuel wise I never did an exact mix per say. the 2nd last ride I had mix'd it IIRC about 40% av, and it was just over half a tank, then before yesterdays ride I topped up the tank, it took 18L straight av gas in, so the previous mix's should of had it for sure 30% av then my 40%, so I guestimated a safe 60% av mix in the last ride, could be more like 70% realistically. again it made no difference from running 30% av and 94 octane or running 60% av and 94, the source of 94 octane chevron is known to be good by the locals with their street race cars and I ran it in my 310 hp yamaha apex straight @20# boost it never threw any det codes on it, had the head shim but never had an issue, from my experience its been a good fuel but that is a totally different machine and a 4 stroke.
The map that TJ had given me hasnt worked at all but again could of been due to the FPR having the line hooked up.
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Looks like one of your problems. The tune I have and the one TJ gave you are very similar. The one I gave you came from TJ but probably a earlier version. Go with the one TJ gave you. They are both for NON rising rate. Your sled originally was rising rate. When Boost-it did the update they never pulled the boost line out they just plugged it. Mine was the same. I did the update myself. So running the NON rising rate tune with the rising rate regulator hooked up is definitely a problem. The old tune with the rising rate worked fine for me. TJ and Neil said I would find it crisper all around with the NON tune and the reg plugged.
Good info and it explains a lot, kinda funny I was told to put the line to the fpr... Ah well haha I got thinking too I wonder if by chance it may be causing the det code or some of it, I'm leaning out my main fuel and Lower rpm trims to remove the "bog" I'm getting then up top rpm I was also trying to really lean it up, to get it not so rich, (higher boost being run than the usual 5# ish) and a probable a/f sensor *may* be reading incorrect as well which wouldn't help. So I wonder if by chance the bottom end is way lean, then on the top end when I let the throttle off it'll be dropping the fuel pressure lots as it's probably going from say +7 psi (in boost) to a - 4 psi change with vacuum behind the throttle blades for a moment , leaning out the factory injectors as well then I go to hit it again and it is lean until the boost picks up and increases the fuel pressure?
Maybe a crazy theory lol. I believe the base line fuel pressure to the regulator alone is 44? 48 psi? So with the boost/vacuum it'll be doing a whole Lotta + and - to the number.
S
studsrsx
New member
This is some interesting info I bought a used kit and have also have troubles tuning it. But when I installed I also ran a boost line to the fpr. My numbers that were in the xic are similar to what you have posted. Maybe have to give that a try. On that note what kind of clutching are you guys running. I'm using the dalton weights at about 76 grams with a red/black primary spring that came with the kit
Yeah take that line off the fpr and run the numbers and see how she goes!
My clutching I am 76g as well how ever I opted to go with what most seem to run, and so I contacted mtntk and got theirs, my primary is pink spring, secondary black yellow and 44-48 helix. *so far* it's been good. clutching works great and I have no complaints. However I am not terribly fussy, when you stab the throttle it seems to be dang near stock like. Clutches didn't heat up badly I don't think.
otherwise....
Today I got out, I re "torqued" my knock sensor, only able to get a wrench in there so I gave it a snug down as to what I know I did before, spec is 14 ft pounds so not much torque. I also removed the line from the fuel pressure regulator and put in the numbers I was sent from boost it.
Down low at approx 3k feet ish it had a bog when stabbing the throttle. (just playing the throttle on the way up the mountain). Got up top at about 6k feet or so, it seemed to run good, I think I could of leaned it out but my replaced o2 sensor never showed up unfortunately.
I turned the boost up to approx 7# again and did a few small pulls and on off the throttle. No complaints there, it did not throw the det code. However literally after a few pulls I blew a hole in my exhaust! Turns out the stock exhaust temperature bung cracked around the factory welds and the whole thing blew out! .... So the rest of the ride I putted along so everybody else could still have some fun, it explains for me why I was noticing more and more underhood exhaust noise over the course of rides. I'll have to weld it and keep an eye on it.
So not as good of an update I had hoped for but what do yeah do! Fingers crossed for next Sunday that I can confirm the det code is gone.
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Another update. I went out today and it did still throw the det code, however it seemed like it did less often... maybe?. the sled runs much better with out the vacuum line to the FPR. and I did very little no to tuning/playing with the XIC box. Just altitude trims to get the fuel where I needed it.
I haven't swapped the knock sensor yet so I will for next ride., Exhaust is not rubbing anything on the front bumper anymore.
I got a new o2 sensor installed, It's certainly reading good now, I never noticed any lean points but who knows. I studied the gauge playing on off the throttle lots in boost on a flat landing, it shows it leaning up when letting off the throttle then you punch it and it does pull down to proper a/f in boost which would be normal. So I never noticed anything doing that and it never threw the DET code during that, Just other times when I got playing around and flying up some hills. I'm wondering if the set point for the controller when It starts to add fuel for boost needs to be sooner? maybe between the throttle flips when it goes lean, then you punch it and the boost is right there every time that it may be running lean for the moment it takes to set off the det code?
IT has a Bog or stutter on the low rpm say after letting off and coasting down/stopped then you punch it. but if you roll the throttle it's not there. Watching the a/f it doesn't seem to change really, if the sleds running/idling at ~13:1 or 14 it stays at the same reading during the bog then it dips down to ~11 or so once the boost kicks and the sled revs up, doesn't go rich or lean.
On the XIC controller IT has the threshold setting, I need to study it better, boost it recommended -8". I tried -10" and one setting lower than that and IT seemed to make the stutter worse, I tried -6" and it seemed better and boost more fluid perhaps, on the trail I tried -4" and it's hard to say if it helped any or not though.
So that's currently where I'm at now,
I haven't swapped the knock sensor yet so I will for next ride., Exhaust is not rubbing anything on the front bumper anymore.
I got a new o2 sensor installed, It's certainly reading good now, I never noticed any lean points but who knows. I studied the gauge playing on off the throttle lots in boost on a flat landing, it shows it leaning up when letting off the throttle then you punch it and it does pull down to proper a/f in boost which would be normal. So I never noticed anything doing that and it never threw the DET code during that, Just other times when I got playing around and flying up some hills. I'm wondering if the set point for the controller when It starts to add fuel for boost needs to be sooner? maybe between the throttle flips when it goes lean, then you punch it and the boost is right there every time that it may be running lean for the moment it takes to set off the det code?
IT has a Bog or stutter on the low rpm say after letting off and coasting down/stopped then you punch it. but if you roll the throttle it's not there. Watching the a/f it doesn't seem to change really, if the sleds running/idling at ~13:1 or 14 it stays at the same reading during the bog then it dips down to ~11 or so once the boost kicks and the sled revs up, doesn't go rich or lean.
On the XIC controller IT has the threshold setting, I need to study it better, boost it recommended -8". I tried -10" and one setting lower than that and IT seemed to make the stutter worse, I tried -6" and it seemed better and boost more fluid perhaps, on the trail I tried -4" and it's hard to say if it helped any or not though.
So that's currently where I'm at now,
S
studsrsx
New member
The way I understand the baro threshold is its relative to elevation / air quality. So if it's a cold clear day( good air quality ), the number will change as opposed to a cloudy, snowy day( poor air quality). Hence the change in the number for elevation. Does this sound right?
I got emailing neil and he said it's more so for when the fueling for the boost starts, In the manual for the box as well it seem to say much on elevation or air quality. but it utilizes somehow it's own onboard barometric sensor for when boost starts vs the internal map sensor only? Not too clear to me.
he's thinking so far I may have a rich stumble/det code happening. I realize too that when I had the vac line hooked up that my a/f sensor was failing to the lean side so I kept richening up the mixture. which in turn made it run worse and worse too and seemed to increase the det code.
He did ask If I had the line hooked up to the FPR and recommended to try that as it will pull some fuel when you let off the throttle, He did say in the kits they DO run the line hooked up to the FPR. He's given me a few ideas and things to try as well for next weekend.
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I did get out today yep and I'd say I'm finally headed in the right direction.
I swapped my knock sensors just because to cover that basis since i Have another pro rmk. I ALSO hooked back up the line to the Fuel pressure regulator as per Neil's recommendation and saying that's how they run them. I then Leaned up my mid range from the 5500 rpm to 7200 rpm a good bit. and on my ride today It never threw the det code once (for me) I let my father take it for a spin and he opted to hang on the lake and I guess he got it to throw it on him, But for me climbing some hills and playing about it never did once. Oon the lake I was hitting it lots on and off on purpose and doing some pulls then let off and hit it. it never once threw the det code for me.
So with that in mind I must of been having the rich "false"? det code? explains I suppose why when the snorkel was covered in snow the one ride that it threw the code then as well, would of made it go way rich. you just don't know what the sleds doing in the mid range fueling when shes running up so fast. Even as it stands I could be on the lean side perhaps? I wouldn't really know. I still have from a stand still throttle pull that bit of bog/stutter happening for a moment, once your moving its fine.
I also still don't like seeing the a/f read 16/17:1 down the trail but.... i guess that's just the modern 2 stroke sleds!
Once I get out again which will be next sunday I'll re-update again to confirm whether It ran with out the code or not.
Got out again today, it started off going good then it did start throwing the DET code again. I tried leaning up my main overall fueling as I seen my top end was rich but It never seemed to help. I then went to increase the point the box adds fuel for when boost comes on and did a quick pull then my driveshaft broke... not fun, the sleds a 2011 or 2012, If it's anything like the jack shaft which I had break already... I'd bet its hollow drive shaft with some crappy end welds or something.
Sh!tty deal man, I snapped one too, and was in an untowable spot. Pretty cool when you do a full out handstand over your bars going up hill ! Doubled back to the truck to tear shaft out of the spare sled, then double back in to replace. Then snapped the belt drive and had to pull turbo to replace. Back to the trailer at 3:00am......so much fun lol. Hope you get 'er dialed in Octanee
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Really hey? Hmm, others havdsaid the 16-17 was normal, and Neil at boost it figured so, I wonder if it's due to the lower than stock fuel pressure? I can't remember exactly but stock is 60 psi? The regulator on the sled for the kit is 44 psi I believe.
Wow that sure sucks! I'm glad to of been heading out and playing on a hill that was near the hill straight down to the main trail and having enough in the group to help.
Your failure picture is exactly the same as mine! I have a used one on the way, I'm hoping to see if I can beef it up any, add more welding to it and/or add a small plate as well. It's certainly marginal for a stock sled from the factory! At least it's not. Glued in like the newer sleds!
As per instructions on my Dobek Gen4 programmer, they said 14-15 is ideal at low end. Mid range should be 13. Top end should be 12-13.
I'll snap a pic and post it when I can dig it up.
Finally got out again, I noticed something this time, the sled ran good from the trucks up the trail for the first 15km or so, my air fuel was maybe 14-15:1 down the trail, as Scott has said which makes sense to me. not way lean! , it snowed a good foot and a half so I was playing on off the trail at lower elevation, 4500 feet and 5# of boost, never missed a beat. Then after 15 km it threw the det code and I looked at my a/f again, it's gotten worse! It's 17:1 and out of range on my gauge again, sled ran worse and throwing the det code in and off boost again. Just off idle and light throttle cruising and semi moderate as well its running lean. It's been getting worse now for sure.
What I'm thinking now is the tps??? I had replaced it with a used one but what else could be causing the factory efi system to go Lean on its own? I noticed before the stutters where it wanted to bog or stutter and when it did it, it went way lean then caught up again. Once the fuel box for the turbo kicks in she runs right at about 12:1.
Wouldn't be a fuel pump as it'll flow when she's under load. And light throttle shes leaning up.
D
What I'm thinking now is the tps??? I had replaced it with a used one but what else could be causing the factory efi system to go Lean on its own? I noticed before the stutters where it wanted to bog or stutter and when it did it, it went way lean then caught up again. Once the fuel box for the turbo kicks in she runs right at about 12:1.
Wouldn't be a fuel pump as it'll flow when she's under load. And light throttle shes leaning up.
D
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