Losing my mind with misfire
04-11-2020, 03:23 PM
#1
Junior Member
Thread Starter
Losing my mind with misfire
Hi guys,
2001 CLK320. Misfire on cylinder. So far I've changed the injector, the sparks plugs, spark leads, and now also the terminal connector plug on the coil packs and swapped coil packs around to check they were ok. Still Misfire on 4. This is killing me, the car is mint other then that, my husband and I are at our wits end with it. We were considering the MAF but would a misfire only on 4 not be weird if it is the sensor. Engine light on constantly and the car will randomly maybe one a month drive like a dream for no reason. Head is melted
2001 CLK320. Misfire on cylinder. So far I've changed the injector, the sparks plugs, spark leads, and now also the terminal connector plug on the coil packs and swapped coil packs around to check they were ok. Still Misfire on 4. This is killing me, the car is mint other then that, my husband and I are at our wits end with it. We were considering the MAF but would a misfire only on 4 not be weird if it is the sensor. Engine light on constantly and the car will randomly maybe one a month drive like a dream for no reason. Head is melted
04-12-2020, 03:34 PM
#2
Junior Member
Thread Starter
Update changed the MAF and still misfiring on 4 but it's only one code for the misfire now, before it was showing misfire and cylinder 4 open now it's only misfire
04-13-2020, 06:49 PM
#3
MBWorld Fanatic!
Here's an excellent article on diagnosing/repairing MB misfire issues.
http://www.mercedesmedic.com/mercede...sfire-problem/
Following are some additional suggestions:
Only replace the MAF with a OE (genuine MB) or OEM (Bosch) unit, as there have been numerous forum members who purchased repair parts on Amazon, eBay etc., which turned out to be substandard knockoffs. At the top of the page, in the 'Marketplace', you'll find a list of forum sponsors who provide both OE and OEM repair parts at very reasonable prices.
Now that you have replaced your MAF, how is your car running?
Note: After replacing the MAF sensor, the CEL will remain illuminated, until you perform 3 cold starts. Additionally, there are a number of sensors that the ECM uses to detect fault codes. When a sensor sees an emission fault, it's readiness status changes from 'supported' to 'not supported', even if you cleared the previous trouble codes with a OBDII scanner. However, if the repair was successful, the sensors will automatically change back to 'supported', after driving at least 200 miles.
http://www.mercedesmedic.com/mercede...sfire-problem/
Following are some additional suggestions:
Only replace the MAF with a OE (genuine MB) or OEM (Bosch) unit, as there have been numerous forum members who purchased repair parts on Amazon, eBay etc., which turned out to be substandard knockoffs. At the top of the page, in the 'Marketplace', you'll find a list of forum sponsors who provide both OE and OEM repair parts at very reasonable prices.
Now that you have replaced your MAF, how is your car running?
Note: After replacing the MAF sensor, the CEL will remain illuminated, until you perform 3 cold starts. Additionally, there are a number of sensors that the ECM uses to detect fault codes. When a sensor sees an emission fault, it's readiness status changes from 'supported' to 'not supported', even if you cleared the previous trouble codes with a OBDII scanner. However, if the repair was successful, the sensors will automatically change back to 'supported', after driving at least 200 miles.
