MHD Datalog

Cyless · 04-09-2022, 09:39 PM

So I just got my MHD adapter and my super license today and I decided to monitor a pull (it wasn't a proper datalog pull) and was wondering if anything seemed off. I will do a proper one tomorrow or something because I've been trying to deal with some sort of exhaust/engine stumble on idle, but the stumble isn't that bad or anything it's just every 30 seconds or so you'll feel a stumble go through the car and if your by the exhaust then you can hear some sort of pop in the exhaust, the pop isn't that load and bothersome I just want my car running in top shape.

No engine codes except 29E0 and 29E1 but I cleared them and going to see if they come back soon. Spark plugs been replaced, coils been replaced, Injectors been replaced with used index 9 but didn't have time to replace the seals and decouplers because I was in a time crunch at the time but since then bought all the seals and decouplers I just need to put them in.

Datalog:https://datazap.me/u/cyless335xi/dat...og=0&data=3-21

bimmerguy1210 · 04-10-2022, 12:56 AM

Replace the seals and decouplers on the injectors ASAP... Your injectors could be leaking raw fuel down the exhaust causing those pops (essentially what the burble tune does). Get index 11 or 12 if you can also if you’re tuned. Index 9 are the known to be the least reliable index

Cyless · 04-10-2022, 04:11 PM

I just replaced my decouplers and seal but the problem still exists. I went to see if I had any codes with MHD and the only thing that showed up was 2 shadow codes: 2FCA and 2FDA. I went to record a new datalog today and the rail pressure PSI dropped below 500.

New Data Log: https://datazap.me/u/cyless335xi/dat...0&data=3-21-22

I'm completely stock no tunes.

Dave92N54 · 04-11-2022, 02:09 PM

Quote:

Originally Posted by Cyless

I just replaced my decouplers and seal but the problem still exists. I went to see if I had any codes with MHD and the only thing that showed up was 2 shadow codes: 2FCA and 2FDA. I went to record a new datalog today and the rail pressure PSI dropped below 500.

New Data Log: https://datazap.me/u/cyless335xi/dat...0&data=3-21-22

I'm completely stock no tunes.

Where/when did it drop below 500? It's above 500 that entire log. It does get low in high RPMs though (around 1500psi). Could be bad HPFP but based on your fuel trims and the throttle closure as the pressure dropped along with it peaking at 2700psi, I'm inclined to believe it's not the HPFP. I'd definitely be considering your injectors. Index 9 are indeed the worst of the bunch. My car had Index 9s when I bought it, 2 were leaking and another 2 were just bad.

Cyless · 04-11-2022, 03:59 PM

Quote:

Originally Posted by Dave92N54

Where/when did it drop below 500? It's above 500 that entire log. It does get low in high RPMs though (around 1500psi). Could be bad HPFP but based on your fuel trims and the throttle closure as the pressure dropped along with it peaking at 2700psi, I'm inclined to believe it's not the HPFP. I'd definitely be considering your injectors. Index 9 are indeed the worst of the bunch. My car had Index 9s when I bought it, 2 were leaking and another 2 were just bad.

617.3 is time when the rail pressure dropped to 435 on the second datalog. I don't really know which ones to replace if it were to be my injectors because I have zero codes and no misfire on start up, only a slight misfire when its idling but other than that the car is completely fine when driving, no hesitation, no rough running or any of that. To my knowledge the car has never gotten its valves cleaned also.

Cyless · 04-30-2022, 08:20 PM

I was told it might be the battery because it didn't hold charge that well and I kinda needed one in the first place but I lt was not the battery. I'm starting to run out of money trying to fix this problem!! I honestly have no idea what it could be now. Could it be my mosfets on my DME or catalytic converter, O2 sensor or what? I got a post cat O2 code today but Idk anymore, I'm about ready to give up. Any help would be appreciated.

Cyless · 04-30-2022, 11:22 PM

So I was driving it tonight and some hesitations/misfire under load came up (separate issue from what I've been having) so I'm gonna replace some injectors but when I turn I off the car is the LPFP sensor supposed to jump up to 80 and stay? I thought when you turn it off its supposed to go to 60 if im not mistaken.

04-09-2022, 09:39 PM	#1
Cyless Private First Class 9 Rep 137 Posts Drives: 2007 BMW 335xi Join Date: Sep 2021 Location: Michigan iTrader: (0)	MHD Datalog So I just got my MHD adapter and my super license today and I decided to monitor a pull (it wasn't a proper datalog pull) and was wondering if anything seemed off. I will do a proper one tomorrow or something because I've been trying to deal with some sort of exhaust/engine stumble on idle, but the stumble isn't that bad or anything it's just every 30 seconds or so you'll feel a stumble go through the car and if your by the exhaust then you can hear some sort of pop in the exhaust, the pop isn't that load and bothersome I just want my car running in top shape. No engine codes except 29E0 and 29E1 but I cleared them and going to see if they come back soon. Spark plugs been replaced, coils been replaced, Injectors been replaced with used index 9 but didn't have time to replace the seals and decouplers because I was in a time crunch at the time but since then bought all the seals and decouplers I just need to put them in. Datalog:https://datazap.me/u/cyless335xi/dat...og=0&data=3-21
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04-10-2022, 12:56 AM	#2
bimmerguy1210 Enthusiast 92 Rep 269 Posts Drives: E90 335i, E93 335i Join Date: Feb 2019 Location: Los Angeles iTrader: (0)	Replace the seals and decouplers on the injectors ASAP... Your injectors could be leaking raw fuel down the exhaust causing those pops (essentially what the burble tune does). Get index 11 or 12 if you can also if you’re tuned. Index 9 are the known to be the least reliable index
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04-10-2022, 04:11 PM	#3
Cyless Private First Class 9 Rep 137 Posts Drives: 2007 BMW 335xi Join Date: Sep 2021 Location: Michigan iTrader: (0)	I just replaced my decouplers and seal but the problem still exists. I went to see if I had any codes with MHD and the only thing that showed up was 2 shadow codes: 2FCA and 2FDA. I went to record a new datalog today and the rail pressure PSI dropped below 500. New Data Log: https://datazap.me/u/cyless335xi/dat...0&data=3-21-22 I'm completely stock no tunes.
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04-30-2022, 08:20 PM	#6
Cyless Private First Class 9 Rep 137 Posts Drives: 2007 BMW 335xi Join Date: Sep 2021 Location: Michigan iTrader: (0)	I was told it might be the battery because it didn't hold charge that well and I kinda needed one in the first place but I lt was not the battery. I'm starting to run out of money trying to fix this problem!! I honestly have no idea what it could be now. Could it be my mosfets on my DME or catalytic converter, O2 sensor or what? I got a post cat O2 code today but Idk anymore, I'm about ready to give up. Any help would be appreciated.
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04-30-2022, 11:22 PM	#7
Cyless Private First Class 9 Rep 137 Posts Drives: 2007 BMW 335xi Join Date: Sep 2021 Location: Michigan iTrader: (0)	So I was driving it tonight and some hesitations/misfire under load came up (separate issue from what I've been having) so I'm gonna replace some injectors but when I turn I off the car is the LPFP sensor supposed to jump up to 80 and stay? I thought when you turn it off its supposed to go to 60 if im not mistaken.
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