C36 Notorious Flat Spot Issue.
Thread Starter
Senior Member
Joined: Dec 2005
Posts: 370
Likes: 0
From: Lebanon
1995 C 36 AMG; 1992 W124 300E (M103 Ex Mosselman TT KIT) was 320hp @10psi now stock :(
C36 Notorious Flat Spot Issue.
I have gone thru everything to get rid of the flat spot but i just cant seem to figure it out. 
i have a new harness for the engine, gearbox and even the electronic throttle was rewired.
i have new OVP
i have a new Air mass.
Car is always tuned up and it is powerful as it can be.
yet i have the flat spot.
any help is much needed,.....
i have a new harness for the engine, gearbox and even the electronic throttle was rewired.
i have new OVP
i have a new Air mass.
Car is always tuned up and it is powerful as it can be.
yet i have the flat spot.
any help is much needed,.....
Thread Starter
Senior Member
Joined: Dec 2005
Posts: 370
Likes: 0
From: Lebanon
1995 C 36 AMG; 1992 W124 300E (M103 Ex Mosselman TT KIT) was 320hp @10psi now stock :(
i will be trying a new overload switch tomorrow i think and maybe also a cam position sensor. but i did disengage the cam phasing and nothing changed bar the loss of few trqs low down :P
on the star scanner everything is in good order. and cam phasing is working fine thus cam sensor should be ok. might need a new cranck sensor??? im out of ideas here. i know the harness is in good condition.
on the star scanner everything is in good order. and cam phasing is working fine thus cam sensor should be ok. might need a new cranck sensor??? im out of ideas here. i know the harness is in good condition.
Super Member
Joined: Oct 2008
Posts: 837
Likes: 25
From: seattle
1990 300ce supercharged and intercooled
The m104 has an inherent flat spot at right under 4,200 rpm if that is what you are talking about. It has to do with the intake and cam settings. There is nothing wrong it is just a switch point. When you turn off the resonance flap at this point the volumetric efficiency change is huge. I did some tuning on this in n/a form with standalone and was really surprised at the change.
Thread Starter
Senior Member
Joined: Dec 2005
Posts: 370
Likes: 0
From: Lebanon
1995 C 36 AMG; 1992 W124 300E (M103 Ex Mosselman TT KIT) was 320hp @10psi now stock :(
i have seriously reduced it if not taken it out. i do think there is a point at 3700 where i can feel a small dip but i have to drive more to find out. but i have solved what i was suffering which was a flat spot from 3400 till 4000 rpm, which was a huge one. turns out mu OVR was cooked. seems the electronic throttle old wires had cooked my new OVR not the car has everything new.
MAF
ALL kinds of harnesses
OVR
and i hope that once for all my car runs perfect.
not the car has everything new.MAF
ALL kinds of harnesses
OVR
and i hope that once for all my car runs perfect.
Trending Topics
MBWorld Fanatic!
Joined: Mar 2010
Posts: 5,889
Likes: 323
From: Land of mountains, cheese, chocolate and watches
12' W204 C63 AMG coupe "T-Rex", 12' W451 Smart Fortwo Pulse (99' W202 C43 AMG + Ultima Can-Am sold)
I also hope it runs well now 
but don't go overboard with it and end up bending the vehicle 
but don't go overboard with it and end up bending the vehicle
MB World Stories
The Best of Mercedes & AMG
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Flawlessly Restored Mercedes 190E Evo II Heads to Auction
Verdad Gallardo
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know
Verdad Gallardo
Mercedes EQS Gets A Major Update: Everything You Need to Know
Verdad Gallardo
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve
Verdad Gallardo
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping
Verdad Gallardo
10 Most Reliable Mercedes-Benz Models You Can Buy Used
Verdad Gallardo
Thread Starter
Senior Member
Joined: Dec 2005
Posts: 370
Likes: 0
From: Lebanon
1995 C 36 AMG; 1992 W124 300E (M103 Ex Mosselman TT KIT) was 320hp @10psi now stock :(
it runs gr8 and now with the new stiff spring, semi slicks and the 208 AMG55 front roll bar its a dream to drive i just need the rear bar and im done modding the susp. next mod is prolly a super charger. will be a few months before i dare make that move but im sure ill do it.
MBWorld Fanatic!
Joined: Apr 2010
Posts: 4,437
Likes: 43
From: PDX
1999 C43, 2008 P30 E63, 2014 SQ5, 2024 Model Y Performance
it runs gr8 and now with the new stiff spring, semi slicks and the 208 AMG55 front roll bar its a dream to drive i just need the rear bar and im done modding the susp. next mod is prolly a super charger. will be a few months before i dare make that move but im sure ill do it.
Thread Starter
Senior Member
Joined: Dec 2005
Posts: 370
Likes: 0
From: Lebanon
1995 C 36 AMG; 1992 W124 300E (M103 Ex Mosselman TT KIT) was 320hp @10psi now stock :(
Yeah the c 43 has the same one as the 36 at 27mm thickness front and 16mm rear. The c 43 has stiffer front springs than the 36 and softer rear springs than the 36. The clk 55 has a 31mm front bar but I still haven't found a rear one so I have no specs on that but I expect it to be atleast 18mm at the rear.
MBWorld Fanatic!
Joined: Apr 2005
Posts: 3,784
Likes: 84
From: SCV SoCal
2002 CLK430
Did someone say sway bars? 
Before swapping the rear bar, it's usually beneficial to identify exactly what one is going after. In my case that's important because aside from not being able to drive, I have an open diff. The last couple of paragraphs at this link discuss sway bar tuning.
Before swapping the rear bar, it's usually beneficial to identify exactly what one is going after. In my case that's important because aside from not being able to drive, I have an open diff. The last couple of paragraphs at this link discuss sway bar tuning.
MBWorld Fanatic!
Joined: Mar 2010
Posts: 5,889
Likes: 323
From: Land of mountains, cheese, chocolate and watches
12' W204 C63 AMG coupe "T-Rex", 12' W451 Smart Fortwo Pulse (99' W202 C43 AMG + Ultima Can-Am sold)
MarcusF thanks for the info 
I love the 911 lifting its inner front wheel Many racing cars of the 70's used to do that often. Looked real cool 
I love the 911 lifting its inner front wheel Many racing cars of the 70's used to do that often. Looked real cool
Thread Starter
Senior Member
Joined: Dec 2005
Posts: 370
Likes: 0
From: Lebanon
1995 C 36 AMG; 1992 W124 300E (M103 Ex Mosselman TT KIT) was 320hp @10psi now stock :(
i know marcus with a stiffer rear i might risk more inside wheel spin. thing is the bar is offered if found t usd50 which is nothing and i get to keep my original so i can test out the setups as i please. Now with the front bar in the car is really good but understeers on the tight turns as expected. im hoping the rear bar will help reduce that a little.
MBWorld Fanatic!
Joined: Mar 2010
Posts: 5,889
Likes: 323
From: Land of mountains, cheese, chocolate and watches
12' W204 C63 AMG coupe "T-Rex", 12' W451 Smart Fortwo Pulse (99' W202 C43 AMG + Ultima Can-Am sold)
Perhaps finding a way to adjust the drop links on the sway bar would be a good way of going and fine tuning the set up depending on conditions. In my Porsche racing days, we even disconnected them when the track was wet so as to soften the suspension and avoid brutal break away.
Super Member
Joined: Aug 2009
Posts: 998
Likes: 70
From: Oakland
W210 DRFT BNZ
I recreafted all the affected harnesses on my 1996 C36. I have a brand new OVP. I have a new MAF. New Knock sensors. New plugs, wires + coils. New Crank and CAM position sensors. New ATF fluid. Resealed vacuum, no loss. I have a short 'cool' air intake by HKS, heatshielded with lexan by me.
I DYNOed the car after all this. The flatspot is still there. It is a dip in torque right when the resonance flap switches, according to the Bentley product familiarization section.
Would make sense if the torque dip is a direct result is simply resonance charging our of phase. See below:
I DYNOed the car after all this. The flatspot is still there. It is a dip in torque right when the resonance flap switches, according to the Bentley product familiarization section.
Would make sense if the torque dip is a direct result is simply resonance charging our of phase. See below:
MBWorld Fanatic!
Joined: Apr 2010
Posts: 4,437
Likes: 43
From: PDX
1999 C43, 2008 P30 E63, 2014 SQ5, 2024 Model Y Performance
I recreafted all the affected harnesses on my 1996 C36. I have a brand new OVP. I have a new MAF. New Knock sensors. New plugs, wires + coils. New Crank and CAM position sensors. New ATF fluid. Resealed vacuum, no loss. I have a short 'cool' air intake by HKS, heatshielded with lexan by me.
I DYNOed the car after all this. The flatspot is still there. It is a dip in torque right when the resonance flap switches, according to the Bentley product familiarization section.
Would make sense if the torque dip is a direct result is simply resonance charging our of phase. See below:
I DYNOed the car after all this. The flatspot is still there. It is a dip in torque right when the resonance flap switches, according to the Bentley product familiarization section.
Would make sense if the torque dip is a direct result is simply resonance charging our of phase. See below:
Super Member
Joined: Aug 2009
Posts: 998
Likes: 70
From: Oakland
W210 DRFT BNZ
Some reading: http://usuarios.multimania.es/cporsc...a/varioeng.htm
More reading: http://www.chrysler300club.com/uniq/.../ramtheory.htm
More reading: http://www.chrysler300club.com/uniq/.../ramtheory.htm
Thread Starter
Senior Member
Joined: Dec 2005
Posts: 370
Likes: 0
From: Lebanon
1995 C 36 AMG; 1992 W124 300E (M103 Ex Mosselman TT KIT) was 320hp @10psi now stock :(
jumph4x i still have a tiny dip in my power band at just 3500rpm but before it was a huge flatspot from 3200-4000 rpm.
