Intermittent "Check Engine" light

Mar 3, 2007 | 12:33 PM

ghaffar23

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'08 CL600 with 152k km; '01 E430 4Matic with 433k km; '17 Porsche Cayenne with 130k km

Intermittent "Check Engine" light

So I drove 200 miles, and at the end of the trip, the check engine light comes on. I unplug the battery, and it's reset. Just fine for about a week. Then, it comes BACK on. Then it turns off for about a day, and now, it's back on. I just had it serviced two weeks ago. My car has around 98,600 miles, and I am suspecting that if MIGHT be one of three things: bad O2 sensor, bad MAF sensor, or replacing my cat's. I don't think that any of the three have been done before. If there's any consolation (sp?), the light came back on last night when I put it in neutral, before I apply the parking brake and put the car in park.

Mar 3, 2007 | 02:00 PM

sosh

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From: Philadelphia area

2010 ML550, 2010 E350 4M, 1966 Corvette Convt C2

You most likely have heard many times before that the only way to tell what needs attention is to interrogate the computer with the Star data system at a dealers. Not a free scan at Autozone or such but with the Star system. You can start throwing parts at it but you may or may not correct the problem. Ignoring this can lead to large problems like too much fuel washing down the cylinder walls. Just spend a few dollars and have it diagnosed correctly. At your mileage it could be more than one thing. Its obvious that you have not been doing proper maint as any decent shop as part of a service shoud interrogate the computer.

Mar 3, 2007 | 08:41 PM

ghaffar23

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Joined: Mar 2005

Posts: 531

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'08 CL600 with 152k km; '01 E430 4Matic with 433k km; '17 Porsche Cayenne with 130k km

Quote:

Originally Posted by sosh

Its obvious that you have not been doing proper maint as any decent shop as part of a service shoud interrogate the computer.

Well, it's not that...usually, if it doesn't come up, there's no point in checking. It popped after I took it out of the shop. I am going to have it looked at on Monday. I've always taken it to the stealership, oops, dealership, and yes, pay full price on everything. You know what? One, that's the only option around here, and two, they're honest. Three, it's not like it's coming out of MY pocket. Everything is business write-off, so it doesn't matter what it costs. As long as it's fixed.

Mar 3, 2007 | 09:18 PM

sosh

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From: Philadelphia area

2010 ML550, 2010 E350 4M, 1966 Corvette Convt C2

The dealer I use runs a computer check with every inspection, CEL or not. They have picked up some things by doing so and there is no additional charge on the inspection for that. Its called preventative maintenence. You should have no problem having your dealer troubleshoot this problem its usually quite a simple fix such as an O2 sensor or such. Good luck!!

Mar 4, 2007 | 04:20 PM

MB Fanatic

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From: South Orange County, CA

4 wheels

Its time for a tune up buddy. It could be a bad spark plug and/or wires.

Mar 5, 2007 | 01:33 AM

FlatlineEF9

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From: Hawaii

1996 E320, 2018 Ducati Panigale V4S, 2012 1199 Panigale

same thing happened to me. I reset the ECU (or so i thought) by disconnecting the battery. Little did i know that it doesnt reset anything, it just stores the code and throws up a check engine light later on. Went to the dealer and found out that the original check engine light was from the MAF sensor i replaced before. yes, the cell was still there after reset. not only that, by disconnecting the battery, the interior sensors were throwing error codes as well. I wont ever disconnect my batt to attempt to reset the light again. Take it to the dealer, or find an indy shop with the SDS.