MAP sensor problems?
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From: Keller
clk63, cls55, ml63, (w210) E55
MAP sensor problems?
Can our factory MAP sensors handle high boost? Friends car goes to failsafe at high speeds (5000+ rpm) with 185mm crank and supercharger under pulley. IAT's are in check @ 110 degrees on hard runs. Car starts to have hesitation and rough idle after hard run and then is corrected after restart? Started recently after having current set up for over 5 months now.
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From: CT
E55 AMG
I Basically had the same exact situation, (Same exact setup - 185mm lower and smaller pulley up top) and then it got progressively worse and now i'm having a misfire situation.
Here is a link to my tread:
https://mbworld.org/forums/showthread.php?p=5835004
BUT IF YOU FIND A SOLUTION PLEASE LET ME KNOW, I am going crazy because of this issue.
Here is a link to my tread:
https://mbworld.org/forums/showthread.php?p=5835004
BUT IF YOU FIND A SOLUTION PLEASE LET ME KNOW, I am going crazy because of this issue.
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From: CT
E55 AMG
What is a MAP clamp? I looked online but couldn't find out anything about It on an E55? If you can direct us to the clamp it will be much appreciated!
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From: Palatine, IL
Speedriven
Just a word of caution about map clamps. They are rather dangerous to use. A map clamp limits how much voltage the sensor sends to the ecu and yes it keeps it from hitting a certain voltage and possibly setting a fault code. But at the same time it doesn't actually allow the ecu to know how much boost is actually being made. Altitude and air density change will greatly throw a tune way off even it its somewhat tuned for with the clamp. Map clamps were initially made for cars that both used map and maf sensors, on those cars you could clamp the map voltage and still had accurate metering from the maf.
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14 E63, 05 E55, 03 Evo 8, 08 F250, 06 R6R, 92 Talon TSI, and instability
Just a word of caution about map clamps. They are rather dangerous to use. A map clamp limits how much voltage the sensor sends to the ecu and yes it keeps it from hitting a certain voltage and possibly setting a fault code. But at the same time it doesn't actually allow the ecu to know how much boost is actually being made. Altitude and air density change will greatly throw a tune way off even it its somewhat tuned for with the clamp. Map clamps were initially made for cars that both used map and maf sensors, on those cars you could clamp the map voltage and still had accurate metering from the maf.
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2004 E55 AMG; 1991 Previa
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14 E63, 05 E55, 03 Evo 8, 08 F250, 06 R6R, 92 Talon TSI, and instability
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From: Keller
clk63, cls55, ml63, (w210) E55
Factory MAP sensor is 1.1 bar. Good to @15.8 psi. Something is adapting. Never a problem before......so my question is why now with the vehicle? We are going to disconnect the battery overnight and see what that does. This problem is known throughout the forum with these mods and I'm curious why it's a damn secret fix?
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From: Keller
clk63, cls55, ml63, (w210) E55
Thread Starter
Super Member
Joined: Oct 2012
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From: Keller
clk63, cls55, ml63, (w210) E55
Thread Starter
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From: Keller
clk63, cls55, ml63, (w210) E55
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From: London
2004 E55K AMG Wagon
The MAP sensor is made by Fuji Electric
http://www.fujielectric.com/products...resensors.html
Part EP9631-R3A
It is 2.5 BAR Absolute
http://www.fujielectric.com/products...resensors.html
Part EP9631-R3A
It is 2.5 BAR Absolute
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From: London
2004 E55K AMG Wagon
There is also a Bosch made one, would be interesting to compare the spec of the two different makes. Could that be the missing piece for the 82mm TB issue???
If the map sensor had a slightly different operating tolerance or curve character.
If the map sensor had a slightly different operating tolerance or curve character.
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05 E55 AMG, E320 CDI, Turbo E46 M3,IS300 2JZGTE,VQ35 Turbo Maxima, Mercedes 300D
+100. Should only use MAP/MAF clamp if using additional injector/controller that can read beyond where you are clamping otherwise you are tuning in the dark. I guess I never gave it much thought on the E55, just assumed there was plenty of margin since no one had brought it up.
Just a word of caution about map clamps. They are rather dangerous to use. A map clamp limits how much voltage the sensor sends to the ecu and yes it keeps it from hitting a certain voltage and possibly setting a fault code. But at the same time it doesn't actually allow the ecu to know how much boost is actually being made. Altitude and air density change will greatly throw a tune way off even it its somewhat tuned for with the clamp. Map clamps were initially made for cars that both used map and maf sensors, on those cars you could clamp the map voltage and still had accurate metering from the maf.
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From: Keller
clk63, cls55, ml63, (w210) E55
The MAP sensor is made by Fuji Electric
http://www.fujielectric.com/products...resensors.html
Part EP9631-R3A
It is 2.5 BAR Absolute
http://www.fujielectric.com/products...resensors.html
Part EP9631-R3A
It is 2.5 BAR Absolute
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From: London
2004 E55K AMG Wagon
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From: Atlanta, GA
2005- E55, 2007 GL450, 94 B3000
absolute pressure includes atmospheric pressure. Atmospheric pressure is 1bar. Therefore, we have a 1.5bar pressure sensor. Almost 21psi can be read by the sensor.
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From: Keller
clk63, cls55, ml63, (w210) E55
Renntech knows of this problem with our sensor as do other tuners. Let me explain as an example...... @15lbs of boost our MAP is near max output of 4.5v and tells ECU to allow 1 part fuel.Now at @5v our MAP sensor is maxed and allows 1.5 part fuel and triggers a lean code that causes the limp mode. If, and I say IF, a tuner can tell the map to allow more fuel at different voltage.....problem solved. Most likely, we will need a different MAP sensor.
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From: Keller
clk63, cls55, ml63, (w210) E55
Where are you guys getting this? How about someone talk to Renntech or a master Mercedes tech that researched it. Oh, wait....I did.
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From: Atlanta, GA
2005- E55, 2007 GL450, 94 B3000
It is simple mathematics.
1 bar = 14.5037 psi
Atmospheric pressure at sea level = 1 bar
1.5 bar = 21.7557 psi
2.5 bar = 36.2595 psi
An absolute pressure sensor is reading 1 bar of pressure at sea level. We have a 2.5 bar absolute pressure sensor. It can measure up to 21.7557 psi above atmospheric pressure. The problem is more than likely the scaling of the sensor data via the ME control unit, or fail safe that has not been found in tuning yet. There is much more involved in our vehicles than tuning the engine control unit. Numerous control units have control over power out put. I am one of those, and I have researched the matter.
Last edited by 211.070; Nov 8, 2013 at 11:21 PM.
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From: Keller
clk63, cls55, ml63, (w210) E55
The math is not in question, professor. It is your ability understand we have a 1.1 bar Map sensor. lol
Apparently, you have not. Call Renntech. Call Eurocharged. Hell, just drive a m113k that is producing more than 16+ lbs of boost and get back with me.
Apparently, you have not. Call Renntech. Call Eurocharged. Hell, just drive a m113k that is producing more than 16+ lbs of boost and get back with me.
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From: London
2004 E55K AMG Wagon
Where do i get this simiple?
I have MB STAR which includes WIS & EPC you can look up the exact part number for the MAP sensor.
I have a map sensor from MB its above it clearly states the part number of MB and the actual manufacturer Fuji Electric. The specifiication of the MAP sensor is public information on the website but here it is again.
http://www.fujielectric.com/products...resensors.html
and here is they part number again Part EP9631-R3A it has an operating pressure of 20 - 250 KPa abs, 250 KPa is 2.5 BAR absolute.
You are confusing the physical limits of the sensor vs the data held in the tables in the control units, the MAP sensor is clearly a 2.5 BAR absolute sensor.
