Turbo5cyl Posted February 8, 2017 Author Report Share Posted February 8, 2017 So tonight I did a datalog with VIDA and have some interesting results. I think this is the issue with the weird boost from 0-6 psi. I datalogged during a WOT pull as well and the throttle body is 100% open the whole time. I am going to try another TCV, I REALLY dont see what else it could be. The MAF doesn't seem to be reading absurd numbers. Red line is throttle pedal Green line is throttle body Blue line is MAF reading Check out the throttle body jump in the middle of the graph when I am just rolling on the throttle a little bit Link to comment Share on other sites More sharing options...
savannahvolvoguy Posted February 12, 2017 Report Share Posted February 12, 2017 Hmm... Interesting. I'm interested to see what the experts say about this. Not at all what I would expect to see but these cars ecus make some interesting decisions with regards to torque demand. By the way... This looks like VIDA running on windows 10? Any issues? Link to comment Share on other sites More sharing options...
Turbo5cyl Posted February 12, 2017 Author Report Share Posted February 12, 2017 Me too, I had a 04 T5 before my R and never did I have this issue. The power always felt smooth...I took off the throttle body yesterday and cleaned it (there was quite a bit of oil puddling on the potentiometer in there) but the issue is still there. Yes, my VIDA is on windows 10 home edition and I haven't come across an issue yet! The install is a real PITA though... Link to comment Share on other sites More sharing options...
savannahvolvoguy Posted February 12, 2017 Report Share Posted February 12, 2017 I might have to get with you later about install because everyone needs one. Oil pooling near the Throttle body makes me think PCV. These cars can do some funny things when the PCV starts to go. Has the car's PCV ever been serviced in its lifetime? If not I'd conduct the glove test at the very least. I also see you were reading high baseline with the MAF while idle. I'm not 100% certain how these cars target their boost pressure but if they are looking for a specific air intake instead of boost pressure then a MAF reading higher than it should could result in a low boost. Long Term Fuel Trim should give you a hint as to what's going on there. If the MAF is reading higher than it should then the LTFT might indicate a lean condition. Basically I'm suggesting that maybe a simple clean might yield some results... Just throwing stuff out there to see what sticks. Link to comment Share on other sites More sharing options...
Turbo5cyl Posted February 13, 2017 Author Report Share Posted February 13, 2017 Maybe Ill do a write up as to how I installed mine then although I did find a install guide on Swedespeed that I followed pretty closely for windows 10. I thought about the PCV as well when I saw all that oil, there is definitely an oil coating on the inside of all my post turbo piping. I did the glove test a week ago and it was fine, sucked the glove in no problem. I should check the records to see if it has been changed or not. That thought crossed my mind too. I actually had a code for the LTFT about 3 weeks ago. I pulled the MAF and cleaned it at that point and it has not come back so far. I was reading like 24 kg/h at idle. I see what you are saying about the LTFT affecting boost if it saw it was lean but then wouldn't a hard reset clear that and allow me to hit 15 psi for at least a WOT run until it sees whats going on? Link to comment Share on other sites More sharing options...
savannahvolvoguy Posted February 15, 2017 Report Share Posted February 15, 2017 I'm assuming you got a P0171 code associated with the "too lean" condition? That code is commonly associated with failing MAFs and/or failing PCV systems... among other issues. If you passed the glove test then you're probably good there... thankfully! The code itself is based off a LTFT greater than 20 to 25 lean. LTFT is effectively an average of your STFT over some period of time... I cant remember what that time period is at the moment. A hard reset will reset your LTFT to a normal range but if the issue isn't corrected your STFT will adjust to make up for the difference. Therefore doing a simple hard reset will not necessarily correct the software's attempts to correct for a condition. What are your actual fuel trim values? Good luck! Also, I just bought my VIDA on amazon. I'm looking forward to trying it out. One catch though... My only laptop doesn't have a disk drive so I'll have to source an external one. Hopefully the software doesn't object to that. Link to comment Share on other sites More sharing options...
Turbo5cyl Posted February 16, 2017 Author Report Share Posted February 16, 2017 No it was a different code I had, ECM-0261A I think it was or something like that but that was the VIDA code so a scanner might have come up with something else such as what you said. The MAF might need to be changed but I cant believe that would be the sole issue when it only reads slightly off and only occasionally... Ill check the LTFT and STFT tonight and report back but if I recall correctly, it was around -9% when it threw the code. Ok I understand why a hard reset might not work then. I remember in my old T5, I unplugged the MAF and went for a drive at one point to rule it out as another issue I was having. If I did that here, that should trick the car and not cause a lean STFT right? I bought my VIDA on alibaba but Im almost 100% sure they are all the same! My laptop doesnt have a disk drive either, just rip the DVD on another PC and then run it with a virtual drive and it will be fine. I can send you a copy of 2014D as well. The one that came on my DVD was corrupted so I had to download one. That was actually a big part of my issues.... a 1kb file was corrupted and not letting it install properly. How fantastic.... Went for a drive tonight to check the fuel trims and both the long and short term fuel trims were around 1% so I don't think that's an issue. I tried with the maf unplugged too and still no better. Although with the maf unplugged, the throttle control seemed to be a bit smoother. Doesn't feel like there is a spike in acceleration. Link to comment Share on other sites More sharing options...
savannahvolvoguy Posted February 17, 2017 Report Share Posted February 17, 2017 I agree... without a full blown CEL I think its unlikely for MAF issues to be the sole cause of a 33% reduction in boost pressure. In my experience the p80 cars really dont like having the MAF disconnected but I don't know how the newer P2 cars respond. They use a dedicated boost pressure sensor so they might be able to infer some form of AFR without the aid of a MAF. I'm sure its something more complicated than can be explained by fuel trim. Unfortunately that's largely the extent of my knowledge when it comes to exploring boost pressure issues. We know for sure its an issue of the computer requesting less boost... so that's a path to follow. I don't suppose there's any chance of the BCS being either nonfunctional or connected incorrectly? Link to comment Share on other sites More sharing options...
Turbo5cyl Posted February 17, 2017 Author Report Share Posted February 17, 2017 I have talked to a few others who have said the map is plenty good enough to run with the MAF unplugged. Im sure the car runs off the O2 sensor and reads the AFR from there and adjusts too. Well thank you for all your help this far! I am going to try another ECU, I feel like the ECU in my car was swapped for some reason because I do not see what else is the issue. Does anybody know whether an 05 SR m66 ECU will drop right into my car and run it fine? Is there an issue with the VIN, immobilizer or something else like that being from another car and one year newer? By BCS, you mean boost control solonoid? If so, I have tried another one of those and it was not any help. Link to comment Share on other sites More sharing options...
laird Posted February 17, 2017 Report Share Posted February 17, 2017 You can't just swap ECUs, they are car coded. I read your posts quickly, have you verified the accuracy of your boost gauge? Link to comment Share on other sites More sharing options...
Turbo5cyl Posted February 17, 2017 Author Report Share Posted February 17, 2017 Damn...maybe ill have the dealer reflash it. I checked it against another gauge I have and it showed the same figures. Its reading almost identical to the boost pressure sensor in the car too. Link to comment Share on other sites More sharing options...
Midnight Caller Posted February 18, 2017 Report Share Posted February 18, 2017 Unfortunately you can only install a "virgin" ECU and do an ECM reload... Or clone yours into a second hand one. Link to comment Share on other sites More sharing options...
savannahvolvoguy Posted February 18, 2017 Report Share Posted February 18, 2017 Yeah but what's the likelihood of the ECU going bad? Have you noticed any performance change or do you think it has been this way as long as you've owned the car? Are there any modifications? Also a +/- 1% fuel trim is basically perfect so that's definitely NOT your problem. I think with that you can rule out MAF, vacuum leaks, probably O2 sensors, and probably PCV (which you've checked as good with the glove test as well). With your boost control solenoid ruled out I'm not sure what else to check. Will VIDA give you a readout of air fuel ratio? A rich AFR at WOT might indicate that the car is requesting boost but something is preventing it from building. Good luck! Link to comment Share on other sites More sharing options...
Turbo5cyl Posted February 18, 2017 Author Report Share Posted February 18, 2017 Ok thank you for the information on the ecu guys. I maybe thought it was swapped for another ecu maybe that was programmed for lower boost. maybe from a t5 or 2.5t. I haven't noticed the car perform worse than when I bought it but it doesn't feel quite as fast as I expected it to. Its a stock car, just got a boost gauge in it. VIDA will give me AFR in the form of lambda. I did some pulls today and with the MAF unplugged, I was seeing a lambda of 0.73 (afr = 10.7) and with it plugged back in, I was seeing 0.83 (afr = 12.2). An AFR of 12.2 seems very lean for a turbo car though.... Link to comment Share on other sites More sharing options...
hootie6828 Posted February 19, 2017 Report Share Posted February 19, 2017 If you have the maf unplugged, the ecu will just substitute a value which it knows the car will run on. You can't really use that to compare to anything else. Link to comment Share on other sites More sharing options...
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