W211 e55 amg not running correctley
#26
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Did you unplug the throttle body to do it? The TB and bypass valve have the same kind of plug and can be mixed up. There are also a couple good places to create a major vacuum leak like the little Y pipe crankcase vent under the TB.
If i remember right, there's a metal tube that pushes into the back of the SC, and one on the drivers side valve cover that get pulled loose and missed a lot. A mechanic not very familiar with these engines won't find these right away. Don't give up yet, you may have fixed it already but left behind a big vacuum leak.
If i remember right, there's a metal tube that pushes into the back of the SC, and one on the drivers side valve cover that get pulled loose and missed a lot. A mechanic not very familiar with these engines won't find these right away. Don't give up yet, you may have fixed it already but left behind a big vacuum leak.
#27
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E55 amg w211
Thanks for your reply. Iv double checked everything.
i never unplugged the tb. Just moved it to one side.
what I have done is I unplugged the map sensor and ran the car. And it idles a lot better and doesn’t smell of fuel anymore.
so I’m not sure if the map sensor I fitted is faulty.
its a Bosch one I fitted.
once I plug the map sensor in the car won’t even drive. Black smoke coming from exhaust which is a sign of running extremely rich. Also the idle is terrible. Once I unplug it clears up and idles ok.
i never unplugged the tb. Just moved it to one side.
what I have done is I unplugged the map sensor and ran the car. And it idles a lot better and doesn’t smell of fuel anymore.
so I’m not sure if the map sensor I fitted is faulty.
its a Bosch one I fitted.
once I plug the map sensor in the car won’t even drive. Black smoke coming from exhaust which is a sign of running extremely rich. Also the idle is terrible. Once I unplug it clears up and idles ok.
Last edited by Pd9264; 11-24-2018 at 02:21 PM.
#28
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Weird. I guess send it back and try another one. If that doesn't work it might be time to pay for a proper diagnosis. Check the map sensor wiring for a bare spot or were it might be rubbing against metal.
#30
ive heard these cars are extremely sensitive to aftermarket MAP sensors..I don’t t know if Bosch is the default brand for the sensor when these cars were new?.. However I have read that anything but a factory MAP sensor wreaks havoc on these engines..Just read a thread on another forum where a guy was fighting issues for a year which included changing 3 different MAP sensors..In the end,,the car only ran correctly on the factory MAP sensor.
#31
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E55 amg w211
It was a faulty map sensor i fitted.
Took it back and got a replacement now car seems fine. Although still reading a faulty o2 sensor. But I got one on order.
as far as I’m aware it is a factory oem sensor by Bosch.
Took it back and got a replacement now car seems fine. Although still reading a faulty o2 sensor. But I got one on order.
as far as I’m aware it is a factory oem sensor by Bosch.
#32
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E55 amg w211
Spoke to soon.
car is back to playing up again.
scanned with icarsoft.
p0235
short circuit to ground.
so now I’m thinking map sensor may be fine but the wiring could be at fault. That could be why sometimes it’s fine and sometimes it’s not.
Read the values on the sensor and it reads between 390-415mbar constantly fluctuating. Should it do this or be steady.
im thinking it has a cracked wire somewhere or loose connection.
car is back to playing up again.
scanned with icarsoft.
p0235
short circuit to ground.
so now I’m thinking map sensor may be fine but the wiring could be at fault. That could be why sometimes it’s fine and sometimes it’s not.
Read the values on the sensor and it reads between 390-415mbar constantly fluctuating. Should it do this or be steady.
im thinking it has a cracked wire somewhere or loose connection.
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E55 amg w211
Just a quick update.
i decided to put some fuel injector cleaner in gas tank. And car hasn’t played up since.sk im thinking that maybe one or even more of the fuel injectors was playing up.
i decided to put some fuel injector cleaner in gas tank. And car hasn’t played up since.sk im thinking that maybe one or even more of the fuel injectors was playing up.