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Discussion Starter #1 (Edited)
Help!..SC and other issues.. Help!

Hello everyone I have learned so much from this forum..thank you!!

I purchased my car 3 weeks ago and have had a ton of issues with it running smoothly.

This is a list of what I have done with it so.far

Changed plugs
Changed air filter
Cleaned oil seperator
Cleaned maf
Checked the k40 relay
Checked the solder on the board that the k40 is in and it was fine.

Originally the cel was on and the car would go into limp mode before I did everything on the list above. The cel is no longer on. So the car ran great after cleaning the maf it was very fast and I drove it on a 200 mile trip and checkcked the mileage and it was right at 28, I thought everything was fixed.

Two days later and the car is sluggish. I checked and cleaned the Maf again but no difference in performance.

I now know that the supercharger is not engaging and I think that is why it is so sluggish. It will engage when I start the car leave it in park and rev the engine but once I drive the car it stops engaging and if I then pull over put the car in park the supercharger will not engage again until I shut the car off and start it back up.

I have checked the hoses to the supercharger and they look good. I unplugged the maf and the car drove the same sluggish way although no cel came on. So I am assuming that the maf is bad. Although I do not want to spend $200 on a guess. Why would it run great after it was cleaned and then just fail a few days later? Could it be something else??

Also I have a problem with the top going back up after it has been down while and it is hot out. The trunk opens but then it gets stuck and i can still hear the pump going. I searched for hours on how to fix this and know it is the micro switch but my question is which switch is it and is there instructions on how to get to it?

Thank you all for everything so far.

I greatly appreciate any help with the issues I am having currently.

BTW..I love the car!!!

Tony
 

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The top may be a microswitch or it could be a code in the ECU. I just had My codes reset by an Indy shop for $95 and it saved me the $400 required to replace all the top microswitches. search for my post about "which Microswitch" it has some good trouble shooting information. However all my microswitches worked great it was an ECU fault. The same may be true for the supercharger.

Check all the grounds on the supercharger and all the connections.
 

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Supercharger clutch issues

Hi Tony
I had my supercharger clutch replaced last year (2012) on my 1999 slk230 (80000miles). It was the noise which alerted me first - it was intermittent and sounded like marbles rattling around at first, until it got so bad it sounded like I was dragging a load of tin cans. Boyfriend popped the bonnet and that's when we saw the supercharger clutch occasionally stopping.
Didn't notice any difference in performance, either before or afterwards. Cost me about £350.00 - it is a known issue with the R170's.
Hope this helps, even it if just to know that you are not alone!

Lady Noyes - England








Hello everyone I have learned so much from this forum..thank you!!

I purchased my car 3 weeks ago and have had a ton of issues with it running smoothly.

This is a list of what I have done with it so.far

Changed plugs
Changed air filter
Cleaned oil seperator
Cleaned maf
Checked the k40 relay
Checked the solder on the board that the k40 is in and it was fine.

Originally the cel was on and the car would go into limp mode before I did everything on the list above. The cel is no longer on. So the car ran great after cleaning the maf it was very fast and I drove it on a 200 mile trip and checkcked the mileage and it was right at 28, I thought everything was fixed.

Two days later and the car is sluggish. I checked and cleaned the Maf again but no difference in performance.

I now know that the supercharger is not engaging and I think that is why it is so sluggish. It will engage when I start the car leave it in park and rev the engine but once I drive the car it stops engaging and if I then pull over put the car in park the supercharger will not engage again until I shut the car off and start it back up.

I have checked the hoses to the supercharger and they look good. I unplugged the maf and the car drove the same sluggish way although no cel came on. So I am assuming that the maf is bad. Although I do not want to spend $200 on a guess. Why would it run great after it was cleaned and then just fail a few days later? Could it be something else??

Also I have a problem with the top going back up after it has been down while and it is hot out. The trunk opens but then it gets stuck and i can still hear the pump going. I searched for hours on how to fix this and know it is the micro switch but my question is which switch is it and is there instructions on how to get to it?

Thank you all for everything so far.

I greatly appreciate any help with the issues I am having currently.

BTW..I love the car!!!

Tony
 

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This is a list of what I have done with it so.far

Changed plugs
Changed air filter
Cleaned oil seperator
Cleaned maf
Checked the k40 relay
Checked the solder on the board that the k40 is in and it was fine.

<SNIP>
I now know that the supercharger is not engaging and I think that is why it is so sluggish. It will engage when I start the car leave it in park and rev the engine but once I drive the car it stops engaging and if I then pull over put the car in park the supercharger will not engage again until I shut the car off and start it back up.

I have checked the hoses to the supercharger and they look good. I unplugged the maf and the car drove the same sluggish way although no cel came on. So I am assuming that the maf is bad. Although I do not want to spend $200 on a guess. Why would it run great after it was cleaned and then just fail a few days later? Could it be something else??
I would suggest that your inspection of the K40 might not have discovered all the issues.
Even if you buzz out the circuitry, it is obvious from the heat damage seen on the board that this gets very warm, and so will have maximum risk of an intermittent connection because of a crack or a dry joint only when warm.
Hence the practice of resoldering all the joints, even if the board looks OK. (This will also reduce the residual stresses, so reduce the risk of cracking in future.)

I would also be inclined to check the contacts of the relays themselves, to ensure they are making correctly.

When I do mine, later this w/e, I also want to know what is on the other side of these joints that keep failing; if they can get *that* hot, any form of heat-sink would improve issues. (Obviously not electronics, since hot enough to melt solder *from inside the component* will kill the component, so simple electrical relay or poor contacts.) Heat comes from a resistance, so the soldered joint will not fail itself once made properly. But a dry joint can generate heat, as can some resistor loads.
Anon
 

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Discussion Starter #5
Thanks for the replys, I will recheck the relays. But it seems that the SC works untill it is put under the load of the car actually driving, it works when the car is first started and in park, but then when i put it in drive and accelerate it seems to kick in for a few seconds and then shuts down permanently until the car is restarted again. So if the relays were the issue would they turn the SC on in the first place?
 

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Is go back as check the plugs, I bought a rough shape 230 and went with some crazy super super quadruple platinum from pep boys and it ran worse than before! Took two more sets until I found the right plugs ( and this forum) and it runs like a champ !
 

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Discussion Starter #7
the dealer put the plugs in, I bet they used the cheapest ones available. Can spark plugs stop the SC from working properly???
 

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Hmmm if the dealer replaced the plugs should be correct, but when I had bad plugs it was barely running it ran in limp mode and sc never ran. Not sure just throwing it ou there. I wonder if it would be worth putting a obd reader on see the codes? But again I would assume the dealer would have done this?
 

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K40; why does it fail?

<SNIP>
When I do mine, later this w/e, I also want to know what is on the other side of these joints that keep failing; if they can get *that* hot, any form of heat-sink would improve issues. (Obviously not electronics, since hot enough to melt solder *from inside the component* will kill the component, so simple electrical relay or poor contacts.) Heat comes from a resistance, so the soldered joint will not fail itself once made properly. But a dry joint can generate heat, as can some resistor loads.
Anon
So now I have the K40 unit stripped, I appreciate that the other side of these failed solder joints is just a bus bar to a connector.
And so these connectors must be making poor contact, hence resistance, hence heat. I suspect the pins are marginally spec'd (there are some large pins and some slender pins, and the ones that melt the solder are all slender pins.
So in order to avoid the repetition, be sure to put contact lube/cleaner onto the connectors A and D. (In fact, for a high power switching unit like this, all of the plugs would be usefully lubricated with contact grease.)

I checked all the relays in the box, and the NC are all N/C, and the NO contact to a trivial resistance. So no problem on that side of the board. I even followed them out to the connector pins, with no trouble. (apart from the damaged joint for pin A3.) Oh, and all the fuses demonstrated continuity.
More anon.

NC = Normally Closed contact on the relay, closed when the relay is unpowered.
NO = Normally Open contact on the relay, closed only when the relay is powered.
N/C = Not Connected.
 

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I checked the plugs they are the expensive quad electrodes so I do not think that is the problem. it had a cracked hose coming off the oil separator that I changed and test drove the car and now the sc is working but the car was still not running right and cel came on I scanned it and got p0301...I am at my wits end with this car!!! Anybody have any ideas??
 

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Thanks for the replys, I will recheck the relays. But it seems that the SC works untill it is put under the load of the car actually driving, it works when the car is first started and in park, but then when i put it in drive and accelerate it seems to kick in for a few seconds and then shuts down permanently until the car is restarted again. So if the relays were the issue would they turn the SC on in the first place?
Your symptoms sound similar to another thread:

Anon.. I am getting a good boost, when the car is cold - Could it be a temperature switch or sensor, the computer did pick one up as a fault, when car is warm, lets say 10 minutes driving the boost is gone ?? F)
And so the cause could be similar; intermittent operation of the SC is based on temperature of the boards, and a dry joint caused by the heat degrading the solder. Resoldering the joints on the K40 still seems to be a good starting point.

Anon
 

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Got in it today for quick run SC Worked fine. when I punched it the car became sluggish around 5000 rpm and just stayed there without shifting to a higher gear then the cel started blinking and then stayed on.. a scan came up with p0300 p0301 p0303 p0304..I am flipping going crazy!!
 

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P0300 Random misfire detected
A. Random misfire
B. Random misfire, TWC damaging
P0301 Cylinder 1 misfire detected Cylinder 1 misfire, TWC damaging
P0302 Cylinder 2 misfire detected Cylinder 2 misfire, TWC damaging
P0303 Cylinder 3 misfire detected Cyilnder 3 misfire, TWC damaging
P0304 Cylinder 4 misfire detected Cylinder 4 misfire, TWC damaging
 

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OK, so I'm no expert, but it sounds like the plugs are the issue. Each plug has its own coil yes? and surely they cant all be duff? Sounds to me like someone has put in iridium quad plugs, believing the hype that they give a better burn and more power, but actually they are firing too soon and messing with the timing so the ECU is disabling the supercharger? Another possibility, could it be that the timing chain is stretched and is putting the timing out?

Again, I must stress that these are suggestive questions, not definitive solutions.
 

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Not one size fits all

P0300 Random misfire detected
A. Random misfire
B. Random misfire, TWC damaging
P0301 Cylinder 1 misfire detected Cylinder 1 misfire, TWC damaging
P0302 Cylinder 2 misfire detected Cylinder 2 misfire, TWC damaging
P0303 Cylinder 3 misfire detected Cyilnder 3 misfire, TWC damaging
P0304 Cylinder 4 misfire detected Cylinder 4 misfire, TWC damaging
I checked the plugs they are the expensive quad electrodes so I do not think that is the problem. it had a cracked hose coming off the oil separator that I changed and test drove the car and now the sc is working but the car was still not running right and cel came on I scanned it and got p0301...I am at my wits end with this car!!! Anybody have any ideas??
Thanks to Leapyfish for providing some reality based on the facts you had already given.
My K40 diagnosis was based on symptoms, not on reported codes, and so missed that important point.
And having had a good result, I was happy to share it (even if it was not relevant). Hope this didn't mislead you too much.
However, since the K40 is so quick and easy to pull out and resolder, I will be sure to include this in any engine diagnosis.

Comments about the plugs; it may be that the plugs are not to the correct spec.
At one point, NGK produced "V" plugs that had a paladium tip plug, with a fine central electrode (for improved gas flow around the spark), which I fitted to my Vauxhall Nova with expectation of great benefit. After a short period, I found they mis-fired, so pulled the plugs, only to find the central tips had completely disappeared on all four plugs, and the fact the engine ran at all was based on the CDI being good enough to drive a spark across a 4mm gap (compared with 0.5mm nominal). Back to the BPR8ES (from BPR8EV) and normal service was resumed. Low tech suited that engine.
So do check the spec (example based on NGK nomenclature "8"s); if they have fitted cold plugs ("7"s) that will run better when cold, but will overheat when hot, resulting in pre-ignition.
If you have a heavy right foot, you might be able to justify hotter plugs ("9"s, that run better in a hot engine) but nominal spec is typically good enough.
 

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Old skool logic

Mixing some old skool logic with modern computer stuff.

If you had coke in your system that is running hot, that might accelerate the pre-ignition issue that would be a trigger for the computer to record a mis-fire. This would probably be symmetrical across all four cylinders.
But when a significant fault is reported for the engine, then as a safety measure, the "performance enhancers" like a SC tend to be disabled. The fault does not need to be directly involved in the operation of the SC.

Other (mature) members of this forum recommend Techron (in USA, see here) to clean the passages, injectors, etc, and this would clear the upper cylinder coke deposits (if relevant).

Interesting to decide what could constitute a mis-fire, to get reported. I suspect pre-ignition would be more likely than late, so running lean to make cylinder surface run hot may contribute (see MAF for too much air or Techron for blocked nozzles giving less fuel than scheduled), soft plugs not cooling enough (as mentioned above) or coke glowing (hence Techron to clean up). The alternative of coke causing the compression ratio of the engine to be increased is also relevant (again, Techron), and may combine with other mechanisms.

None of these are expensive, and worth doing even if it doesn't provide the ultimate resolution of the problem.
HTH,
Anon
 

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Gearbox not shifting

Got in it today for quick run SC Worked fine. when I punched it the car became sluggish around 5000 rpm and just stayed there without shifting to a higher gear then the cel started blinking and then stayed on.. a scan came up with p0300 p0301 p0303 p0304..I am flipping going crazy!!
Your experience with the gearbox not shifting is similar to mine; when the SC is inactive, then the engine doesn't achieve the power/speed required to change the gearbox, and it stays in a gear (much) longer than expected. Once the SC works again, the gearbox goes back to nominal.
So don't be concerned, the box is not at fault, and will "repair" itself to work as expected once the engine is working as expected.
 

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Plug colour?

I checked the plugs they are the expensive quad electrodes so I do not think that is the problem.
Were the plugs a normal light-gray/brown?
You may be able to determine a mixture problem "old skool" by looking at the plug colour.
You can even kill the engine at revs or under load, to see what the colour is then, but with an auto-box, this may be more challenging...
ANon
 
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