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Re soldered K40 Module and now rough idle/running and no power

  #1  
Old 01-20-2014, 06:36 PM
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Default Re soldered K40 Module and now rough idle/running and no power

ok, ever wish you hadnt started something?

ive had an intermittant prob of lack of power on accelleration occuring few times a week and getting worse.

I suspected the K40 soldering problem but also ordered a new MAF.
I fitted the new MAF at the weekend and it didnt improve things so I pulled the K40 relay unit out and yes a nice big dry joint in the usual place on the connector to plug A, also noticed much of the soldering on the board looked like it was going dry so I re soldered the whole board and re installed it!

now when i start the car it starts and runs fine for about 3-5 mins then idles very rough for couple mins then switches back to idleing smooth and this dance continues.

on driving the rythm continues and when running rough there is virtually no power, strugles to get over 2k revs and when in a smooth phase it runs almost normal with much more power and revs are back up but still not perfect?

pulled the K40 module back out and inspected and double checked the soldering but visually everything seems fine

does anyone have any ideas
Thanks
Mark
 
  #2  
Old 05-06-2014, 12:15 AM
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might replace relay just to be sure. camshaft sensor? fuel pump?
 
  #3  
Old 05-06-2014, 03:47 AM
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Problem was solved a while ago, ended up being faulty Cam sensor and a faulty NEW MAF sensor, just goes to show dont assume its good if its new!
 
  #4  
Old 05-06-2014, 08:47 PM
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[QUOTE=techcareuk;165420]ok, ever wish you hadnt started something?

ive had an intermittant prob of lack of power on accelleration occuring few times a week and getting worse.

I suspected the K40 soldering problem but also ordered a new MAF.
I fitted the new MAF at the weekend and it didnt improve things so I pulled the K40 relay unit out and yes a nice big dry joint in the usual place on the connector to plug A, also noticed much of the soldering on the board looked like it was going dry so I re soldered the whole board and re installed it!

now when i start the car it starts and runs fine for about 3-5 mins then idles very rough for couple mins then switches back to idleing smooth and this dance continues.

on driving the rythm continues and when running rough there is virtually no power, strugles to get over 2k revs and when in a smooth phase it runs almost normal with much more power and revs are back up but still not perfect?

pulled the K40 module back out and inspected and double checked the soldering but visually everything seems fine

does anyone have any ideas

in the USA we had the SLK 230 with the 111 engine. it had issues with engine oil sucking in through the supercharger and also into the intercooler and then into the mass airflow sensor. you would find oil in the airmass sensor.
 
  #5  
Old 05-07-2014, 03:54 AM
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[QUOTE=chassis221;166290
in the USA we had the SLK 230 with the 111 engine. it had issues with engine oil sucking in through the supercharger and also into the intercooler and then into the mass airflow sensor. you would find oil in the airmass sensor.[/QUOTE]





Yes Chassis221, the oil in the MAF has now developed!
the new MAF sensor fitted earlier this year has failed, some oil is visible at the MAF joint to the intercooler (the end with the clips)
I've cleaned the oil separator and have ordered a new MAF and oil separator and am looking into airbox mods that replace the air filter with 3x separate filters fitted to the 3 pipes originally fitted to the airbox.


I prob should start a new thread on that but if you have any advice on what the people in the US did to resolve the problem that would be great! also any ideas on how to clean out the air path (intercooler and pipes etc) without total dismantle?
 
  #6  
Old 05-09-2014, 06:56 PM
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you cleaning the separator and attached pipes should solve the oil in the maf issue.
 
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