Mercedes-Benz engine repair questions and answers
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1585 Questions
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Why when driving you give the car gas and nothing happens.monique_adams2001 - 2001 Mercedes Benz C320 - Engine - 5/12/2013-
5/12/2013 JimmFirst step - have the check engine light or stored fault codes scanned - for free - at any local auto parts store; Advance Auto, Auto Zone, NAPA. Then, post a reply as 'add answer' for more assistance.
Possible Causes of Engine Hesitation or Stumble:
Dirty fuel injectors (cleaning the injectors often fixes this)
Dirty air filter (change filter)
Dirty / clogged fuel filter (change filter)
Bad MAP (manifold absolute pressure) sensor
Bad TPS (throttle position) sensor
Bad or dirty MAF (mass airflow) sensor
Low fuel pressure (leaky fuel pressure regulator or weak fuel pump)
Vacuum leaks (intake manifold, vacuum hoses, throttle body, EGR valve)
Bad gasoline (fuel contaminated with water or too much alcohol)
Sometimes, what feels like a hesitation is actually ignition misfire rather than lean misfire. The causes of ignition misfire may include:
Dirty or worn spark plugs
Bad plug wires
Weak ignition coil
Wet plug wires
5/14/2013 monique_adams2001I was told it could be the fuel rail. Would that fall under the same guide lines of fixing it with the above suggestions????? -
5/12/2013 BillIf engine RPMS climb and engine revs, then transmission the culprit. You really haven't given us a lot to work with.
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Rough idle and stalling. What is wrong?Bernie - 2000 Mercedes Benz CLK320 - Engine - 5/12/2013176,000 miles running on rough idle and stalling. Replaced all original Bosch Ignition coil packs, wireset, sparkplugs, injectors, MAF & Crank position sensors, gas and fuel filters. Still runs rough idling and stalling. Fuel pressure is at 57 psi on idle. ...-
5/12/2013 BillSure sounds like a vacuum leak. Recheck all vacuum hoses and if any seem marginal, replace, also replace PVC valve and vacuum line. Could also be a stretched timing chain/belt or tension er. Let us know what you turn up.
5/14/2013 BernieI usually check vacuum leaks by spraying choke carb spray over possible points where vacuum takes place like intake pipes, hoses, injector seats, brake servo etc, with vacuum guage hooked up. idle would normally change but no reaction so far but a persistent misfire. I will be checking the cable connector to the crank position sensor. I have consulted 5 major MB dealer technicians and no one has ever resolved the issues. The mileage is low for chain to get streched on MB engines.
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How to replace warning dash lightsbeta10191962 - 1995 Mercedes Benz SL320 - Engine - 5/9/2013when starting the car several warning lights do not come on. All warning lights should come on and then go off each time the car is started.
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Throttle/pedal possition sensor not working?krtherapper - 2001 Mercedes Benz S430 - Engine - 5/4/2013i replaced the pedal/sensor and my car is not reading it. what do i do next?-
5/4/2013 JimmThere is no programming required for the throttle position sensor (TPS) - there may be an issue with the TPS connector or wiring to / from the sensor itself - down by the accelerator pedal on the interior floorboard.
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Throttle possition sensor i purchased another one and car is not reading it.krtherapper - 2001 Mercedes Benz S430 - Engine - 5/4/2013just wondering how does it work? do i have to do something to make it work or do i have to bring it in to a shop to have that pedal reprogrammed back.
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5/4/2013 JimmThere is no programming required for the throttle position sensor (TPS) - there may be an issue with the TPS connector or wiring to / from the sensor itself - down by the accelerator pedal on the interior floorboard.
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5/2/2013 JimmYes, the EHA (electrohydraulic actuator) for the valves is self-adjusting during operation. It's designed to tweak the mixture either lean or rich depending on changing conditions and O2 feedback. It is a fuel pressure regulator that adjusts the fuel mixture depending on certain conditions.This valve is used to control the flow of fuel to the fuel distributor.
If this valve fails, you may notice poor idle, lack of power, or a vehicle that will not start at all.
The EHA is adjustable but only affects the lower part of the fuel distributor. You'll need a gauge with the proper metric fitting to test the upper and lower fuel distributor pressures to compare the difference.
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My car runs fine when I first start it up, 10 min or so later it turns off and want start. It turns over maybe fuel pumpgreenlofts - 2000 Mercedes Benz E320 - Engine - 4/18/2013When car set for 30min or so it start up again -
What tools do i need to repair head gasketskatins - 1999 Mercedes Benz ML430 - Engine - 4/5/201313000 miles. was told that it needed heads
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4/5/2013 MikeReplacing head gaskets is not an easy DIY job. The first tool you need is a repair manual.
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What could be the cause of failure to start on cold mornings?larryking4605 - 2003 Mercedes Benz C320 - Engine - 4/5/2013The car starts normally and runs well except for cold weather. It cranks and tries to run but dies and seems to be flooded. When it does start it smokes and I smell gasoline. It also sometimes idles roughly when stopping at a stop light. It runs fine the rest of ...
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4/5/2013 Ben in JoppaIt could be the catalytic converter building up. Getting gunked up and causing too much back pressure. Could be as simple as a few taps with a hammer to free up debris in cat or res. Or, take it out and drive it like you stole it for a little while and try to burn the carbon build up out of there. Hope that helps.
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What should I expect?diamond7two - 2003 Mercedes Benz C230 - Engine - 4/3/2013Hello...my check engine light came on, I went to autozone and they gave me the codes: p0126, p0600, and p0456.I don't drive this car everyday so I don't know if the temp will correct itself when it warms up. I have to get my oil changed and will have the mechanic ...-
4/3/2013 HouseCallAutoFirst thing you do is buy your own code reader at amazon for $21. Buy it here >> http://www.amazon.com/.../ref=sr_1_1
Now it takes 2 minutes to read codes, no reason why you have to go to AZ. AZ has a no-erase policy. You can plug in the reader and erase the codes and now do nothing. Wait and see what codes return and then act on them. The code P0126 does not appear to be a valid code that is applicable to this vehicle. It is a code for real, just not for this year, make and model. Maybe you read it wrong? Maybe was a P0125? The P0456 will likely be a small leak from a evap hose. The P0600 just means that you have codes present. The P0600 will go away when the other two codes are solved. cannot quote this until you answer about P0126
4/4/2013 diamond7twoHi, thanks for your response. Sorry that was a typo, the code is p0128. I already went to AZ but I will pick up a reader. The guy at AZ printed out receipts with the codes on them and he told me that the receipts may say Volkswagon but it can apply to my car as well.
4/4/2013 HouseCallAutoThe P0128 is a stuck open thermostat (the engine is running too cold) so change the stat.
4/5/2013 diamond7twoThank you, will do.
4/8/2013 diamond7twoHi again, I got the code reader and I am having a problem with it. I goes through the first five steps fine (from CAN- to ISO) I get LINK ERROR! then it either quickly goes back to the main screen or it has said NO CODES twice. I'm not sure what to do next.
4/10/2013 diamond7twoIn case anyone else reads this, if you have the same problem with the code reader that I mentioned, when it comes to the part of the instructions in the manual that advise you to turn your key but not start your engine...ignore it, start your engine and the reader should work from there. I'm learning! lol
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Why won't my car startantj1536 - 1997 Mercedes Benz E320 - Engine - 4/2/2013my car won't start its gas in it but i,m not getting no fuel&no spark
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Why won't my car start in its not getting no spark or no fuelantj1536 - 1997 Mercedes Benz E320 - Engine - 4/2/2013what do you recommend i chang 1 of the coil &sparkplugs
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4/2/2013 HouseCallAutoYou MUST plug in a code reader and see what fault codes are stored. This is how cars (even MB) is diagnosed. We don't just throw parts at it and hope. You may have a bad crankshaft position sensor or something else. Buy a code reader at amazon for $21 and plug it in, it takes 2 minutes and then tell me the code numbers on the update. I do not think your plugs or the coil is your cause.
4/2/2013 antj1536i was told its not fire,before the car stop running it had a miss in cylinder4 they change the plug in it started for about 20minutes then it cut off in didn't start back up this car got me real puzzle
4/2/2013 HouseCallAutoIt may need a coil to solve the misfire, yes, but that does not fix a no start. get the code reader and read the codes. This is what I do for a living, 35 years. Its not a puzzle to me, it is just a diagnosis away with the right data.
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4/2/2013 antj1536can u give me a call so u can come fix my problem in I will pay u for your device
4/2/2013 HouseCallAutoI am in NY. Buy the code reader here >> http://www.amazon.com/.../ref=sr_1_1
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MY CAR WON'T START UP ''BEFORE MY CAR STOP STARTING IT WAS SHAKING REAL BAD IN I WAS TOLD I HAVE A MISSantj1536 - 1997 Mercedes Benz E320 - Engine - 4/2/2013NOW ITS NOT STARTING AT ALL IN ITS NOT GETTING NO FUEL& I DON'T KNOW WHAT TO DO I CHANG 1 OF THE COIL
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Car start - engine still warmnadeau.william - 1991 Mercedes Benz 300CE - Engine - 4/1/2013I just purchased this vehicle with 80K miles. On a cold start the engine starts fine and will warm up at 1200-1300 RPM for a minute until warm & then drop to 600-700, which is perfect. Often times, when I have driven the car and then turn the engine off, whether a ...
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Rightside lights are flashing and cant get them to stop on my GLK350 4matic benzrathfelder - 2010 Mercedes Benz GLK350 - Engine - 3/31/2013Right headlight and tail light are flashing even when car is off.
