How about a super discount for the bog fix creator?
You should get a free clutch just for driving more clutch sales!
MHD Updates - Shift Bog (Tq Lim 2048) Delete & PI Safety
- Thread starter Jake@MHD
- Start date
You should get a free clutch just for driving more clutch sales!
Hey J,
I have a Propulsive Dynamics Unit and if I use stage 3 or 2 xHP it jerks, lurches, hesitates under wot. Do you think that this is related to the topic you are talking about here? My DME limiter is being exceeded by xHP? I when using the PD stock transmission flash, or even Alpina flash, the trans is virtually undetectable when shifting. Only in xHP stage 2 and 3 is there an issue.
Thoughts appreciated. Should I reflash OTS v8 with this option checked to fix this issue?
VT
So you see tq lim 2048 at the top of your gears? If so check the box and reflash. If not, it's something to do with your TCU flash. It sounds like the latter.
I think I was not clear. So what you are saying is that in MHD, if I log option "torque nm actual".... then that option would show 2048? You mean 2048 nm - which would be impossible.
VT
It is not torque nm actual, as I said the parameter is called "tq lim active" in the list. It will log various torque limiters, like 1 for traction control, 3/4 for gear shifts, 2048 for "bog". There are no units, it is an arbitrary number referring to the torque limiting strategy used.
@jyamona
Thank you for bog fix. We were waiting for it for a couple of years. Absolutely insane! But after rising boost from 24psi to about 26-28 psi I'm started to getting 29DC(cylinder injection swith off) between every shifts. Looks like hpfp is dropping and not recover fast enough causing error. HPFP replacement did not solve the problem. Same thing. Could you look at the logs.
Specs:
hpfp new
port injection
LPFP
dual 450lph
ADV o2
Thank you for bog fix. We were waiting for it for a couple of years. Absolutely insane! But after rising boost from 24psi to about 26-28 psi I'm started to getting 29DC(cylinder injection swith off) between every shifts. Looks like hpfp is dropping and not recover fast enough causing error. HPFP replacement did not solve the problem. Same thing. Could you look at the logs.
Specs:
hpfp new
port injection
LPFP
dual 450lph
ADV o2
Perhaps you have some JB4 settings wrong, I'm not sure. If you were using whatever @Terry@BMS had as a hack around for "bog fix", you will need to revert it to the way it was originally. Additionally you should check the "PI Safety" flash-time option since you are using port fueling.
Looks like a legitimate fuel pressure issue. But for starters make sure clutch wire is back in and FUD.4 disabled so we see true gear, and log again.
@Terry@BMS
You always promote your JB4 and sell it based on it's features. You rarely toot your own personal horn however and expose how well you support your customers after the purchase.
This is amazing, a guy has an issue, posts on a public forum, you find it within hours and step in to help him out.
I did tag him, but still... pretty good
I was working with him earlier but couldn't really put my finger on it. I told him to come and ask if it was something to do with NLS since that's all I could think of with injector shut off.
Hey guys,
Any movement on a solution for post shift timing drop 3rd to 4th gear on AT cars?
I strongly believe the DME is programmed to limit torque during the shift to scale back too much wheel spin going into the next gear especially in higher gears for obvious safety reasons. It would still be nice to have a little more control over this issue. It seems like when we come up with one fix, the ECU finds other ways to control power during shifts. I was getting torque limit 2048 on my AT until bog fix came out. It helped but now timing drop became more stretched out before recovering. Lol!
Any movement on a solution for post shift timing drop 3rd to 4th gear on AT cars?
I strongly believe the DME is programmed to limit torque during the shift to scale back too much wheel spin going into the next gear especially in higher gears for obvious safety reasons. It would still be nice to have a little more control over this issue. It seems like when we come up with one fix, the ECU finds other ways to control power during shifts. I was getting torque limit 2048 on my AT until bog fix came out. It helped but now timing drop became more stretched out before recovering. Lol!
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We need this shift bog ported to N55! https://datazap.me/u/banks334/2-15-19-e30-44f-hybrid
Now that MHD defined the pids to log torque limiters it seems I have 2048 in almost every log I do now lol
Now that MHD defined the pids to log torque limiters it seems I have 2048 in almost every log I do now lol
I don't think that this would manifest as a "correction." Probably has more to do with tuning that split-second off throttle moment that can induce timing corrections.
No split second off throttle for me. I have seen corrections going into 4th gear after changing tunes. It usually goes away after the DME adapts but still throws a correction here or there during the shift sometimes. Im on stockers and the main thing thats helped me is MHD knock desensitization. I dont have any tuning issues I'm aware of. All parameters in check ie HPFP, afr, lpfp, octane etc. What I was referring to is that normal timing drop we see during the shift. Sometimes on my car I see the drop stretched out a little longer to reduce torque going into the next gear. During my testing, the DME can throw corrections some call false knock or give you a longer timing drop delay. I've concluded the controls are in place to assist with traction so we're not spinning out of control everywhere. Throttle closures, timing reduction, fuel cuts, short shifts, delayed shifts, torque reduction etc. The DME can use any method at its disposal to control how much power to put down during traction events from my experience. Thank God we can tune some of this stuff out but the DME still remains in control most of the time. Otherwise, these beast would be spinning out nearly every give on the 6AT car.
I don't think that's how that works but I'll let someone more knowledgeable chime in.
