Car does not rev well past 4500 on 3/4 to full throttle
Thread Starter
Junior Member
Joined: Sep 2011
Posts: 22
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e240 1999
Car does not rev well past 4500 on 3/4 to full throttle
Hello Folks,
just joined the forum. looking forward to participating.
I have a 1999 e240 petrol autobox. to date has only done 73,000 kms and still runs sweet.
It has an auto box and drove it slowly for a while. recently using kickdown on full throttle to the floor it appears to rev fine from tickover to around 4,500 rpm but then stays there at 4,500 rpm and holds the gear. it really feels "choked" (like it is not getting enough air into the engine) and does/will not really rev past this point on 3/4 to full throttle. however, if you lift off a tad, to about half throttle, it then changes up and continues going as normal.
if you use half to 3/4 throttle from rest it will keep accelerating without this "choking" feeling and and changes as normal and will rev past 4500 rpm nearer to redline. SO, it DOES rev to the redline but not on 3/4 to full throttle.
any help appreciated !
Cheers
Jlee
just joined the forum. looking forward to participating.
I have a 1999 e240 petrol autobox. to date has only done 73,000 kms and still runs sweet.
It has an auto box and drove it slowly for a while. recently using kickdown on full throttle to the floor it appears to rev fine from tickover to around 4,500 rpm but then stays there at 4,500 rpm and holds the gear. it really feels "choked" (like it is not getting enough air into the engine) and does/will not really rev past this point on 3/4 to full throttle. however, if you lift off a tad, to about half throttle, it then changes up and continues going as normal.
if you use half to 3/4 throttle from rest it will keep accelerating without this "choking" feeling and and changes as normal and will rev past 4500 rpm nearer to redline. SO, it DOES rev to the redline but not on 3/4 to full throttle.
any help appreciated !
Cheers
Jlee
Junior Member
Joined: Dec 2011
Posts: 34
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1999 E240 Elegance
Greetings,
I'm not any sort of expert, however, I would start my search at the throttle position sensor (if that is the right name). This is the sensor that determines the position of the accelerator pedal. If you have a look under the bonnet, on the right-handside, towards the windscreen, you'll see a black, round plastic "thing" with a cable attached to it, with the cable dissapearing into the cabin.
I suspect that the unit is failing, resulting in the car's ECU going into a "fail-safe" mode. Is the problem consistent, or does it clear if you switch off, and re-start the car?
Else, it could possibly be the Mass Air Sensor that is failing, resulting in the fuel injection not delivering the correct amount of fuel, thereby "smothering" the motor.
Anyone else? Please correct me if I'm wrong...
I'm not any sort of expert, however, I would start my search at the throttle position sensor (if that is the right name). This is the sensor that determines the position of the accelerator pedal. If you have a look under the bonnet, on the right-handside, towards the windscreen, you'll see a black, round plastic "thing" with a cable attached to it, with the cable dissapearing into the cabin.
I suspect that the unit is failing, resulting in the car's ECU going into a "fail-safe" mode. Is the problem consistent, or does it clear if you switch off, and re-start the car?
Else, it could possibly be the Mass Air Sensor that is failing, resulting in the fuel injection not delivering the correct amount of fuel, thereby "smothering" the motor.
Anyone else? Please correct me if I'm wrong...
Member
Joined: Sep 2011
Posts: 92
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2000 e430 4matic
I had a similar issue which i solved by removing the rear cat and muffler, the inside of the cat blew into the muffler and was clogging my exhaust and choking the engine, try disconnecting your exhaust and take it for a testdrive. If that fixes it you know what's wrong.
MBWorld Fanatic!
Joined: May 2008
Posts: 1,072
Likes: 5
From: Pittsburgh,PA, Cambridge, Ontario, CN
2003 S210 3.8L Brabus wagon
You do not mention if you are in gear and cruising down the highway when revving or sitting stationary. If it is the latter it is a function of MB safety protocol that the engine will not over rev without a load attached namely the transmission engaged. My w124, W210 and W211 all operate that way.
Thread Starter
Junior Member
Joined: Sep 2011
Posts: 22
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e240 1999
been away. just got back.
car is in gear and cruising.
Funny thing is that after i got a new key copied for the car, the car ran perfectly and had no hesitation at all. perhaps due to the battery being disconnected for a while as other work was being done on airbag or the ecu resetting itself with no power and the ecu learning new style driving pattern. also get lots of traffic jams here.
the issue has slowly returned and the rpm at which it does not rev well has slowly declined from being able to redline to 500 rpm increments over the past 5-6 weeks and now back to how it was.
So question is:
A. did the battery disconnection reset something to allow it to rev well and has slowly declined back to normal after traffic jam style driving
B. if so, how can i reset the ECU (without disconecting the battery) to re-learn the non grandad driving style that seems to be ingrained now.
I googled this and found the following procedure to reset ECU on MB cars but does not work on my MB e240 1999 petrol auto. maybe another procedure?
The procedure to reset the ECU is as follows;
"1. Turn the igniiton key to the "on" position which is just before you crank
the engine to start.
2. Press the accelerator to the floor and hold for 5 seconds.
3. Then turn the key to the off position but do not remove the key, then
release the accelerator.
4. Wait at least 2 minutes, the ECU is then reset.
5. ECU is now reset . "
thanks folks
car is in gear and cruising.
Funny thing is that after i got a new key copied for the car, the car ran perfectly and had no hesitation at all. perhaps due to the battery being disconnected for a while as other work was being done on airbag or the ecu resetting itself with no power and the ecu learning new style driving pattern. also get lots of traffic jams here.
the issue has slowly returned and the rpm at which it does not rev well has slowly declined from being able to redline to 500 rpm increments over the past 5-6 weeks and now back to how it was.
So question is:
A. did the battery disconnection reset something to allow it to rev well and has slowly declined back to normal after traffic jam style driving
B. if so, how can i reset the ECU (without disconecting the battery) to re-learn the non grandad driving style that seems to be ingrained now.
I googled this and found the following procedure to reset ECU on MB cars but does not work on my MB e240 1999 petrol auto. maybe another procedure?
The procedure to reset the ECU is as follows;
"1. Turn the igniiton key to the "on" position which is just before you crank
the engine to start.
2. Press the accelerator to the floor and hold for 5 seconds.
3. Then turn the key to the off position but do not remove the key, then
release the accelerator.
4. Wait at least 2 minutes, the ECU is then reset.
5. ECU is now reset . "
thanks folks
Last edited by jlee240; Dec 23, 2011 at 08:49 AM.
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MBWorld Fanatic!
Joined: Feb 2008
Posts: 1,803
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From: Charleston, SC
GL450
Sounds like a bad TPS. See if this is your problem:
https://mbworld.org/forums/w210-amg/...hrottle-2.html
https://mbworld.org/forums/w210-amg/...hrottle-2.html
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Thread Starter
Junior Member
Joined: Sep 2011
Posts: 22
Likes: 0
e240 1999
Saints, thanks for the reply. Nah, car still works fine and will still go into kickdown and drives as normal. Cruise control ok. Just does not seem to rev well. Easing off the throttle to drop revs below 4500 rpm and car accelerates okay until it changes up gear and continues onward and upwards.
Just does not seem to like revving past. 4500 rpm on kickdown. It ran great after battery off and the kickdown rev limit seems to have creeped downwards more and more as I drove it over a period of 6 weeks or so until back to the state of my initial post. Weird! Need enlightened on this weird problem. Bad spark plugs ? Mag ? No clue but wanted to try an ecu reset to rule out anything broken first. Make sense ? Cheers
Just does not seem to like revving past. 4500 rpm on kickdown. It ran great after battery off and the kickdown rev limit seems to have creeped downwards more and more as I drove it over a period of 6 weeks or so until back to the state of my initial post. Weird! Need enlightened on this weird problem. Bad spark plugs ? Mag ? No clue but wanted to try an ecu reset to rule out anything broken first. Make sense ? Cheers
Thread Starter
Junior Member
Joined: Sep 2011
Posts: 22
Likes: 0
e240 1999
Anyone know how to do ecu reset on e240 petrol 1999 without disconnecting the battery? Not sure if I can disconnect the battery without havin to recalibraye other stuff on the car, electric windows, power steering column, abs etc. sorry bit clueless about the e240
Newbie
Joined: Sep 2005
Posts: 13
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You are chasing the wrong direction - you have to get at the cause of the problem - and not just reset your way around the car because it is trying to protect itself (and you) against additional damage.
You need to see ohlord's reply to you and act on it...
You need to see ohlord's reply to you and act on it...
Thread Starter
Junior Member
Joined: Sep 2011
Posts: 22
Likes: 0
e240 1999
not been using the car much but wanted to get this fixed as its bugging me.
UPDATE:
1.Have replaced the non standard fuel filter for original fuel filter (someone said that sometimes the non original restrict fuel pressure so may cause this effect)
RESULT - no change.
then
2. changed the fuel pump (was a litle noisy and had a small leak)
RESULT - no effect but had to be changed anyway
3. changed the mass air sensor (fault code showed)
RESULT - car does rev better and up to redline but car defintley still shows hesitation during the rev range from 4000 upwards but does rev past 4000 now. its like being starved of fuel
Fault codes cleared on the air mass meter but there is one code still showing now whic is "61A" but dont know what this code means. anyone help ?
car is 1999 e240 petrol v6 2.4 litre automatic slushbox.
Cheers
UPDATE:
1.Have replaced the non standard fuel filter for original fuel filter (someone said that sometimes the non original restrict fuel pressure so may cause this effect)
RESULT - no change.
then
2. changed the fuel pump (was a litle noisy and had a small leak)
RESULT - no effect but had to be changed anyway
3. changed the mass air sensor (fault code showed)
RESULT - car does rev better and up to redline but car defintley still shows hesitation during the rev range from 4000 upwards but does rev past 4000 now. its like being starved of fuel
Fault codes cleared on the air mass meter but there is one code still showing now whic is "61A" but dont know what this code means. anyone help ?
car is 1999 e240 petrol v6 2.4 litre automatic slushbox.
Cheers
Last edited by jlee240; Feb 23, 2012 at 09:13 PM.
Thread Starter
Junior Member
Joined: Sep 2011
Posts: 22
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e240 1999
fault code was 61A
Member
Joined: Sep 2011
Posts: 92
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2000 e430 4matic
Yes
that's what I was referring to. I had the insides cat blow out and clog up my muffler, The cat was hollow, the muffler was plugged. Either way you can check to see if either makes a difference by disconnecting the exhaust near the front. There's a spot where you can just take off the bolts near the front of the car. There's easy access, I didn't even have to jack my car up. You may or may not have to depending on your size 
It should take a half hour to an hour maximum to disconnect the exhaust, and after your done take it for a test drive and see if it makes any difference! 
It should take a half hour to an hour maximum to disconnect the exhaust, and after your done take it for a test drive and see if it makes any difference!
