I don’t have any technical data about these coils at hand right now. … I would for instance check for resistance differences between cold and hot condition.
oh, but I don't have a voltmeter at the moment.I don’t have any technical data about these coils at hand right now. … I would for instance check for resistance differences between cold and hot condition.
Regarding the MAF I assume the code came because of unplugging it while engine was running.disconnecting the hot wire (LH) MAF used on my volvos when the engine is running is known to be potentially fatal to them and/or the ECU, but I have no idea about the mercedes HFM implementation. I always shut things off before plugging/unplugging anything.
flakey wiring at the CMP could certainly cause problems.
these codes you're getting, you've reset them and they come back after driving ?
+1 get the car on HFM Scan it will tell you all you need to know and enable correct diagnosis.@speed9644 I recommend getting K-Line interface off ebay and use Mike's HFMScan, it provides digital error codes with correct description with live engine data. I understand it takes time to buy interface on ebay and get it delivered, but looking at date you started this thread it would have taken lot less time.
If it did and there was vacuum leak you should have seen code 13.After a day driving the car, I feel like there's a relation between brake booster and idle, when car is stopped idle is not smooth and it jerks. Is that possible ? Does the brake booster change vacuum/pressure when brake is fully pressed ?
That’s attentive observing!Does the brake booster change vacuum/pressure when brake is fully pressed ?
I have bought an OBD plug in and an ELM327 module, but nothing from mike, eventually it didn't work because module couldn't communicate with the car.+1 get the car on HFM Scan it will tell you all you need to know and enable correct diagnosis.
Ok, I did a quick test yesterday, didn't erase any codes before reading codes, I might erase the codes tonight, go for a test drive and then read codes again and report back.If it did and there was vacuum leak you should have seen code 13.
But weird thing is that failure of brake booster is not common W124's, I will just try to spray a carburetor cleaner spray near the vacuum lines while my assistance is watching the RPG gauge and see if it goes up/down when spraying. That's just an easier test for me because I don't have enough time to leave work and go search for a shop that can make a smoke test.That’s attentive observing!
Vacuum leaks / false air are fundamental suspects in case of bad idle – and if the leak is small enough, it might only occur at operating temperature.
Like anything connected to the vacuum system in principle, the brake booster can have an effect on it.
Besides the moment during which the booster diaphragm is being moved – there could be a crack in it which changes its shape depending on its brake or not brake position.
Do you see an effect when you apply or release the brake or also when you hold it?
Anyway, a brake booster’s involvement could be tested by disconnecting and blocking its vacuum line.
Of course: Don’t drive like that … do that test w/o moving the car!
IMHO the best way to check the intake system in general for false air is using a smoke machine.
ELM327 can not read your engine.I have bought an OBD plug in and an ELM327 module, but nothing from mike, eventually it didn't work because module couldn't communicate with the car.
oh !!ELM327 can not read your engine.
Read carefully my article - which adapter you need to buy ... cost 5 USD.
I can not guarantee that I would see the problem, but your costs at the same time minimal (5 USD for VAG COM 409.1 on ebay.com ).