Power cut off 5 gear high speed.
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C63 Vert
Power cut off 5 gear high speed.
Pushed the car a bit with an buddy in a v8 m3. On the highway coming back 5 gear high speed i would get a cut of power. But not the shaking.
All other gear changes were solid. Is this a fuel pump, a torque converter, tranny issue or something else to investigate.
I kind of recall some of the higher power m278s stock fuel pumps not keeping up. And i likely need to do a fluid change on the tranny at 6 years and 27k miles
All other gear changes were solid. Is this a fuel pump, a torque converter, tranny issue or something else to investigate.
I kind of recall some of the higher power m278s stock fuel pumps not keeping up. And i likely need to do a fluid change on the tranny at 6 years and 27k miles
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From: florida
CLS400-3"downpipes cls63 exhaust and bbk BMS intake AMR rv3.1, 12.1@119mph 1.9 60'
Pushed the car a bit with an buddy in a v8 m3. On the highway coming back 5 gear high speed i would get a cut of power. But not the shaking.
All other gear changes were solid. Is this a fuel pump, a torque converter, tranny issue or something else to investigate.
I kind of recall some of the higher power m278s stock fuel pumps not keeping up. And i likely need to do a fluid change on the tranny at 6 years and 27k miles
All other gear changes were solid. Is this a fuel pump, a torque converter, tranny issue or something else to investigate.
I kind of recall some of the higher power m278s stock fuel pumps not keeping up. And i likely need to do a fluid change on the tranny at 6 years and 27k miles
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C63 Vert
Its not limiter. I can smoothly drive faster and switch gears fine. Its when i gun it in 5th. Feels like im hitting a wall and pulls gas or something. Not a bunch of jerks. no misfires just feels like i hit a wall and i pull back and can drive fine.
No codes.
thinking it is fuel pumps. Wouldnt injectors throw codes?
No codes.
thinking it is fuel pumps. Wouldnt injectors throw codes?
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W218 Stage 2, E85
That's weird. I was racing an M3 a while ago and was around 125mph, don't know which gear, and everything was fine.
Yeah, if injectors stopped, it should throw a CEL. Or if the injectors stopped working for a short time, the CEL should flash and maybe go away once they're back on. Maybe check for any Pending Codes?
Like did it not move at all in the 5th gear or was it slumping a little?
Yeah, if injectors stopped, it should throw a CEL. Or if the injectors stopped working for a short time, the CEL should flash and maybe go away once they're back on. Maybe check for any Pending Codes?
Like did it not move at all in the 5th gear or was it slumping a little?
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Joined: Jul 2019
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C63 Vert
That's weird. I was racing an M3 a while ago and was around 125mph, don't know which gear, and everything was fine.
Yeah, if injectors stopped, it should throw a CEL. Or if the injectors stopped working for a short time, the CEL should flash and maybe go away once they're back on. Maybe check for any Pending Codes?
Like did it not move at all in the 5th gear or was it slumping a little?
Yeah, if injectors stopped, it should throw a CEL. Or if the injectors stopped working for a short time, the CEL should flash and maybe go away once they're back on. Maybe check for any Pending Codes?
Like did it not move at all in the 5th gear or was it slumping a little?
Last edited by cls5504matic; Oct 4, 2020 at 08:45 PM.
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I'm just throwing random questions and see if it can lead to something else.
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W218 Stage 2, E85
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2013 Weistec 540/715 tuned CLS 550, 2008 E350, and '07 Jaguar S-Type R
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I'm not sure why my car was overboosting. I guess I was running free flower intake and exhaust then the tunes anticipated. So a bench tune optimized for a stock cls 550 didn't work. Morendi flashed a bench tune then logged it and changed the tune, by adjusting torque to load and max airflow to address it.
my takaway personally is that morendi's tune process right now of using a bench tune then logging is superior than a my genius with bench tune.
I'd also guess air intake is a pretty big bottleneck. the stock air filters are huge, and take up a lot of the intake tube, aftermarket filters are less than half as thick. but upd does remove them completely from the air intake tube. DTK (RIP) and I were discussing this once on FB. He mentioned he didn't think they did much because they only increased hp by about 10-20 hp and felt that was within the margin of error. But he did feel the black boost, and his custom intake unlocked enough power to be statistically significant. like 40 hp.
I think at this point I would go with black boost when they are on sale. There are some custom intakes out there including scorpion style intakes with top mount intercoolers. which would be a significant gain, more than 40 hp with a tune maybe 70 hp.
