SL/R230: Help!! SL55 AMG intermittent STALLING
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SL500 R230 2004
Help!! SL55 AMG intermittent STALLING**SOLVED**
******THIS HAS NOW BEEN SOLVED-SEE TOWARDS END OF THREAD******
Happy New Year Everyone.
I have an 2004 SL55 AMG (R230), which will stall a least once or twice within 5 mins of driving or start of engine, then after that it is ok. It only stalls at standstill or very low speeds (15 - 20 mph) typically at junctions, turnings where I have to take the foot of the accelerator. Then it is ok as long as I keep driving it.
Does not make an difference it the engine is cold or warm. The strange thing is that Star is not detecting any problems, so I am at a loss in the next step. Additionally I am told this car does not have an MAF sensor.
If anyone has experience of this, or know further tests I can carry out to fix this, I would be grateful. Also this car will use oil, when accelerated hard, in case that has some bearing on the matter.
Work So Far
New Petrol Pump
New Petrol Filter
Clean out of Throttle Body
THIS CAR DOES NOT HAVE A MAF SENSOR.
I really hope I can sort this, because I really like the car. I have access to a STAR system.
Many thanks in return.
Happy New Year Everyone.
I have an 2004 SL55 AMG (R230), which will stall a least once or twice within 5 mins of driving or start of engine, then after that it is ok. It only stalls at standstill or very low speeds (15 - 20 mph) typically at junctions, turnings where I have to take the foot of the accelerator. Then it is ok as long as I keep driving it.
Does not make an difference it the engine is cold or warm. The strange thing is that Star is not detecting any problems, so I am at a loss in the next step. Additionally I am told this car does not have an MAF sensor.
If anyone has experience of this, or know further tests I can carry out to fix this, I would be grateful. Also this car will use oil, when accelerated hard, in case that has some bearing on the matter.
Work So Far
New Petrol Pump
New Petrol Filter
Clean out of Throttle Body
THIS CAR DOES NOT HAVE A MAF SENSOR.
I really hope I can sort this, because I really like the car. I have access to a STAR system.
Many thanks in return.
Last edited by kalsingh1; Mar 28, 2019 at 05:58 AM. Reason: SOLVED
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This might be an issue with the EIS. Mine does something similar where a few times a week it will lose CAN bus connectivity and sort of "reboot" everything. As long as the engine is above idle and the car is moving, it will continue running, but if I am sitting at idle, the engine will shut off. I also have no errors, and other than my hardwired radar detector rebooting and an occasional "replace key" message on the MFD, there are no other symptoms. The only stored errors I could find on SDS are some about "the CAN bus operating in single wire mode" stored in the "Diagnostic System"
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From: Atlanta, unfortunately
'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
Rodney, it seems to me what is needed here and often in other cases is an electronic circuit to monitor a voltage and detect if it has exceeded a range. In this case it could be a very simple circuit that turns-on an LED if the voltage falls below 12 volts. More versatile would be a circuit with a microcontroller (computer) having an Android phone or PC interface. The microcontroller would monitor the voltage and record its maximum and minimum values; through the interface those values could be seen, and if desired conditions that would turn-on an LED could be set. The circuit could be assembled in an hour and would cost about $10.
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SL500 R230 2004
This car in question does not have a distributer cap.
Is there anyway to test if it is the EIS is the problem, or any other way to test for anything else.
I have access to a star system, but has I said before, it does not show any faults. Feels like it is impossible to know where to start.
Is there anyway to test if it is the EIS is the problem, or any other way to test for anything else.
I have access to a star system, but has I said before, it does not show any faults. Feels like it is impossible to know where to start.
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From: Atlanta, unfortunately
'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
Think about what failures could momentarily interrupt the ignition system or the delivery of fuel. Then devise and perform a test for each.
If the EIS is your problem it is failing by dropping power to "circuit 15" -- the source of power for the fuel and ignition systems. To test the EIS for this you would check the voltage on circuit 15 at the cigar lighter or a fuse in one of the front fuse boxes at the moment the engine stalls or otherwise does not run. I presume your EIS would be dropping-out for just a moment, and that is why I suggested a simple circuit that would monitor the voltage on circuit 15 and detect a drop-out. Alternatively, you could connect a multimeter that records maximum and minimum voltage readings.
If the EIS is your problem it is failing by dropping power to "circuit 15" -- the source of power for the fuel and ignition systems. To test the EIS for this you would check the voltage on circuit 15 at the cigar lighter or a fuse in one of the front fuse boxes at the moment the engine stalls or otherwise does not run. I presume your EIS would be dropping-out for just a moment, and that is why I suggested a simple circuit that would monitor the voltage on circuit 15 and detect a drop-out. Alternatively, you could connect a multimeter that records maximum and minimum voltage readings.
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In my case, I have no errors stores in the ECU, EIS, or any other system. The only error I get when I scan the "Body" -> "System Diagnosis" and then I have errors that various CAN bus components are in "single wire mode". My understanding is that this is caused by the EIS, since it's the hub for the car's three CAN buses. I have taken mine out and cleaned all the contacts and looked for any obvious damage, but that did not help. I guess one day I'll replace the EIS, but its not enough of a nuisance to spend the money on it.
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From: Seattle, WA
SL500
A shot in the dark here, but do you experience any issues when you "floor it"? A typical sign that the Accelerator position sensor is failing is the car going into limp mode when you floor it, but a faulty sensor can also produce an error if you let off the accelerator too quickly as the car vassilates between deciding upon congested driving mode, a potential emergency stop, and normal. The accelerator pedal sensor syncs up with the throttle position sensor, and if either is not where it expects the other to be at a given point in time, strange things happen. Usually it's limp mode, but it might be worth checking just in case? Generally when you restart the engine, the symptom disappears. If you have a portable scanner handy, try to search for a code BEFORE restarting the engine, so the code doesn't clear itself. You'll be looking for code PO123, but it'll only show when active and reset once the engine restarts - making it sometimes elusive to pin down. Again, just a shot in the dark.
Last edited by Aussiesuede; Jan 5, 2018 at 10:33 PM.
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SL500 R230 2004
A shot in the dark here, but do you experience any issues when you "floor it"? A typical sign that the Accelerator position sensor is failing is the car going into limp mode when you floor it, but a faulty sensor can also produce an error if you let off the accelerator too quickly as the car vassilates between deciding upon congested driving mode, a potential emergency stop, and normal. The accelerator pedal sensor syncs up with the throttle position sensor, and if either is not where it expects the other to be at a given point in time, strange things happen. Usually it's limp mode, but it might be worth checking just in case? Generally when you restart the engine, the symptom disappears. If you have a portable scanner handy, try to search for a code BEFORE restarting the engine, so the code doesn't clear itself. You'll be looking for code PO123, but it'll only show when active and reset once the engine restarts - making it sometimes elusive to pin down. Again, just a shot in the dark.
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From: Atlanta, unfortunately
'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
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SL500 R230 2004
yes you are right it does usually seem to be related to engine temp - although it would cause a stall , maybe something to try if everything else fails ?
my other suggestion would be, has the car had a remap ? I had a strange edge case problem of engine stumbling on nearly closed throttle. It turned out to be the remap , loading the original MB map completely cured the problem.
my other suggestion would be, has the car had a remap ? I had a strange edge case problem of engine stumbling on nearly closed throttle. It turned out to be the remap , loading the original MB map completely cured the problem.
I have tapped a multimeter to the cigarette lighter, to see what happens to the reading on a hesitation or stall. The car seems to have a personality, as if it knows it is being watched, so is behaving itself. Although this morning it had a quick hesitation once only, but the multimeter still seemed in the range of 13.95 to 14.06 volts. I did not see a massive drop. I am waiting for it to stall, so will report back on the multimeter readings.
Has the cold weather got anything to do with, why it is behaving so far ?
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SL500 R230 2004
I have had the multimeter on the cigarette lighter for the last couple of days, and have had two stalls, with no voltage drop noticed other than 14v when running, and 12v when stalled.I have access to star, is there any way now to connect this, and keep an eye on the fuel pressure, if so does anyone know the sequence on the menu ?
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SL500 R230 2004
apart from checking with a star system linked to the internet ( for the updates ) ie Indy or main dealer I don't know of a way to check the current firmware. I believe some engine mappers use the original file and modify it, so it may even have the same name. I had mine done at a local indy and it wasn't expensive.
Of course the car knows your watching it, intermittent faults - you gotta love them.
I would be surprised if you see anything useful on the lighter voltage using a dvm. You would need a scope setup ideally. Also since this is a supply line, not sure why it would it drop ? If it were a poor connection it would happen at any point during your drive.
So a further suggestion, do you have the TORQUE app and an ELM327. ? You can set it up to measure the accelerator pedal and various other inputs. The refresh rate is a bit slow so you may miss a quick event but
its worth a try since without fault codes the problem is not obvious.
Of course the car knows your watching it, intermittent faults - you gotta love them.
I would be surprised if you see anything useful on the lighter voltage using a dvm. You would need a scope setup ideally. Also since this is a supply line, not sure why it would it drop ? If it were a poor connection it would happen at any point during your drive.
So a further suggestion, do you have the TORQUE app and an ELM327. ? You can set it up to measure the accelerator pedal and various other inputs. The refresh rate is a bit slow so you may miss a quick event but
its worth a try since without fault codes the problem is not obvious.
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SL500 R230 2004
The car has stalled another couple of times, once on a roundabout, the voltmeter did not show any massive drops. I am getting a bit fed up now, just need to get to the cause of it.
Anyone knows anything else, or any further tests, I can get access to a star system from my mate.
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From: Atlanta, unfortunately
'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
Star Diagnosis can monitor most analog signals and display them graphically. The voltage on circuit 15 is what you are interested in. The menu path is something like: control units > Motor electronics > Development data > Actual values > Complete actual value list. If you suspect the fuel pressure or something else is the cause, they can be added to the graph as well, though it may take some time to find what you want since everything is in German.
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From: Atlanta, unfortunately
'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
If the CAN is the failure mechanism then I would think there would be a status set that he would see in Star Diagnosis, yet he sees nothing. Moreover, would you suppose the CAN error would interrupt the flow of data to the Star Diagnosis PC?
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In my situation, there are absolutely no stored errors in any system except that "System Diagnosis" area where it says the CAN bus was operating in "single wire mode". Of course I've not run SDS on it while it "burps" because it happens so rarely, like maybe once or twice a week.
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From: Atlanta, unfortunately
'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
The engine can not be started if it loses CAN network communication with the EIS. But once it is started, if that communication were lost the engine could run normally, and intuitively, for safety reasons Mercedes engineers would not choose to have it quit. And yet if I am wrong and it would quit, then surely it would log a diagnostic code; e.g., "P207D No or incorrect CAN message from control unit N73 EIS Control Unit".
We know from other threads a faulty EIS can cause the engine to quit. In every case I believe the mechanism is a power interruption to the ignition and fuel injection circuits on Circuit 15. The vehicle electrical system can not distinguish between this electrical failure and the driver switching the engine off with the key, and this is the reason no errors are logged.
We know from other threads a faulty EIS can cause the engine to quit. In every case I believe the mechanism is a power interruption to the ignition and fuel injection circuits on Circuit 15. The vehicle electrical system can not distinguish between this electrical failure and the driver switching the engine off with the key, and this is the reason no errors are logged.
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The engine can not be started if it loses CAN network communication with the EIS. But once it is started, if that communication were lost the engine could run normally, and intuitively, for safety reasons Mercedes engineers would not choose to have it quit. And yet if I am wrong and it would quit, then surely it would log a diagnostic code; e.g., "P207D No or incorrect CAN message from control unit N73 EIS Control Unit".
We know from other threads a faulty EIS can cause the engine to quit. In every case I believe the mechanism is a power interruption to the ignition and fuel injection circuits on Circuit 15. The vehicle electrical system can not distinguish between this electrical failure and the driver switching the engine off with the key, and this is the reason no errors are logged.
We know from other threads a faulty EIS can cause the engine to quit. In every case I believe the mechanism is a power interruption to the ignition and fuel injection circuits on Circuit 15. The vehicle electrical system can not distinguish between this electrical failure and the driver switching the engine off with the key, and this is the reason no errors are logged.
