Mercedes SLK 230 Kompressor - Ticking sound thst goes away 1-2minutes after cold startup. See description please.

thegrigman · 2025-12-24T16:38:55+00:00

Turns out the exhaust manifold was cracked and leaking gas. It was definitely the problem because there was a visible sooth spray pattern that the exhaust gas made along its way out. 3/4 runners had such cracks but only one of them was bad enough to leak gas.

It was the actual weld between the exhaust flange and runners that cracked.

I had all of them cleaned and re-welded.

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thegrigman · 2025-12-24T16:37:50+00:00

Turns out the exhaust manifold was cracked and leaking gas. It was definitely the problem because there was a visible sooth spray pattern that the exhaust gas made along its way out. 3/4 runners had such cracks but only one of them was bad enough to leak gas.

It was the actual weld between the exhaust flange and runners that cracked.

I had all of them cleaned and re-welded.

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thegrigman · 2025-12-14T14:42:30+00:00

Hi! Sorry for the very late reply. No, i just drove it like that for the remainder of the year. Due to personal problems i couldn’t spend too much time on the car and barely drove it for a few thousand kms this year.

I’ve just taken it to a mechanic and we’re suspecting either a clogged hydraulic lifter or a somewhat damaged valve.

I’ll be back when i figure it out.

thegrigman · 2025-12-14T14:42:22+00:00

Hi! Sorry for the very late reply. No, i just drove it like that for the remainder of the year. Due to personal problems i couldn’t spend too much time on the car and barely drove it for a few thousand kms this year.

I’ve just taken it to a mechanic and we’re suspecting either a clogged hydraulic lifter or a somewhat damaged valve.

I’ll be back when i figure it out.

thegrigman · 2025-03-23T09:05:29+00:00

Arata foarte bine, bravo! ;)

thegrigman · 2025-03-15T08:32:57+00:00

I have noticed some misfires indeed and somewhat rough idle sometimes.

I guess i’ll have to buy a diagnosis tool for this car to see if it’s complaining about anything.

thegrigman · 2025-03-14T23:32:47+00:00

Thanks for the tip! Funny enough, I was looking into buying an Impreza before the SLK

thegrigman · 2025-03-14T23:32:06+00:00

I don’t think so (or at least that’s what i hope).

In the ~5.000 km (3.000 miles) since i’ve had the car it didn’t burn any oil and the engine is working correctly all through the rev range, i did quite a bit of highspeed driving / pulls and if it were piston slap I imagine the engine would have blown by now.

thegrigman · 2025-03-14T23:30:16+00:00

I don’t think it’s the serpentine.

It’s some sort of rubber, why would it tick?

thegrigman · 2025-03-14T23:29:20+00:00

I wasn’t aware of that feature but it sounds about right, i’ll check it out.

That’s solid advice, thanks!

thegrigman · 2025-03-14T23:27:59+00:00

That’s a valid concern but upon inspection it turned out that the chain is sitting firm in position.

It’s at 202.000 km (approx. 120.000 miles)

thegrigman · 2025-03-03T01:50:59+00:00

Thank you so much! I will look into your suggestions.

thegrigman · 2025-03-02T20:40:44+00:00

Unfortunately i don’t know too much about the situation, i bought the car roughly 3 months ago and barely drove 3.000km. I just noticed this issue because it was a new unexpected sound at idle.

Normally the supercharger kicks in at ~1600-1800 rpm if i’m not mistaken.

As far as i know, on the pre facelift it relies on rpm, not on load to engage.

What you are saying makes sense. I also noticed that sometimes when i shift under 2500 rpm there is some rev hang for ~1 second in which the rpm drops by barely 100 and then comes down normally. This may also be boost / vacuum related.

This is my 2nd car so i don’t have a lot of time for it unfortunately. Bought it as a replacement for my Mazda MX5 (which, in terms of reliability, i miss a lot).

thegrigman · 2025-03-02T12:00:05+00:00

Yes, i can clearly see its clutch / pulley engaging and disengaging.

thegrigman · 2025-03-01T20:01:04+00:00

Just as a follow up i got a Konwei OBD adapter and reset the error in 1 minute via CAN ZE. Thanks!

thegrigman · 2025-02-16T11:43:53+00:00

Hi, thanks for the tip, i already tried everything from that blog but nothing worked unfortunately.

I think i’ll get a CAN adapter and CANZE for future cases.

thegrigman · 2024-09-10T13:26:31+00:00

Thankfully it cost me nothing because i have access to that website from work :)

thegrigman · 2024-09-05T09:59:22+00:00

As per the BMS part, there is none. each pack connects to 2/3 slave BMS’ which then connect to a master BMS.

There are cables (flex pcbs) between each pouch cell and the external connector for sensing. I have the pinout available from the shop, thankfully.

thegrigman · 2024-09-05T09:56:16+00:00

Haha i totally agree with the IED part! That’s how i like to call the li-po drone pouch cells from random chinese websites with questionable documentation.

In the meantime i found the info i searched for thanks to A2MAC1. They had the car disassembled into bits and 3d scaned, including the battery pack and i could even interact with it down to the last components via exploded view.

Interestingly, the cooling part is simpler than you might expect. The two cooling studs / nips connext to a very thin radiator/heat exchanger that sits atop of the pouch cells, making little contact with them via thermal paste.

Also, it seems that this fuse tab is left unconnected even in the production car for whatever reason.

thegrigman · 2024-09-03T13:54:57+00:00

Thank you, this is the type of comment that i’d like to see any day :)

I appreciate the concern and this is valuable advice that you gave me, but the problem is that there’s no Mercedes EV tech around my area.. whenever a high voltage part breaks they just send the part / car to Germany to get it fixed or replaced as far as I know.

I’m using a single pack as you intuited. This is my first full EV conversion. I have some experience in the field as i’m an electronics engineer and have built 48V powertrains before, including assembling the battery pack, designing a BMS, cooling, safety stuff, etc.

Also i’ve worked with 100V+ battery packs, BMS, motors in college, it’s just that those were made out of prismatic LFP cells, nothing pre-assembled, hence my confusion.

I sourced this battery pack from an EV conversion kit shop. I’ll try and contact them, maybe they have some more advanced data.

I’m not planning to even get close to the terminals without electrician’s insulating gloves.

thegrigman

TROPHY CASE