CHECK ENGINE LIGHT STILL ON AFTER APERENTLY FIXING PROBLEM.
Asked by coffeesolutionone18 Aug 31, 2022 at 08:37 PM about the 2008 Mercedes-Benz R-Class R 350
Question type: Maintenance & Repair
Check engine light on. Checked it on
a code reader. It said "spark plugs " 1-
6. CHANGED them AND coils also.
Light came on again! And again it
said " spark plugs" 1-6. I figured give
it time to "reset" it's been a week and
300 miles. What can it be?.... Maybe
the plugs need to be gapped?...
7 Answers
What trouble codes do you have? There's no code for "spark plugs 1 thru 6". Jim
coffeesolutionone18 answered 2 years ago
Thanks for your time....Just checked it again. Code are basically 1-6 Spark plug. Other words: P0 300, P0 301, 302,303,304,305. They say plugs come ready to. NO GAP. at this point I'm going to pull them out again and gap them. I think it's...0/.31?
Ok, so what you have is random/multi cylinder misfire (P0300), misfire cylinder number one (P0301), misfire cylinder number two (P0302), misfire cylinder number three (P0303), misfire cylinder number four, (P0304), and misfire cylinder number five (P0305). Spark plugs and ignition coils are one possibility. You could be looking at bad fuel injectors, intake manifold leak, vacuum hose leaks, bad mass airflow sensor (MAF), if equipped, failing ignition control module (ICM), failing fuel pump, or possibly a bad fuel pressure regulator. There's also the possibility, although remote, that the engine has poor compression due to an engine that's just worn out. Hope that helps! Jim
2008 should be using iridium spark plugs so recapping is not possible without ruining the spark plug. I agree with Jim above, looks like he’s got the right path in mind.
coffeesolutionone18 answered 2 years ago
Makes Sense. Gappings out of the question. I have a gut feeling that for some odd reason if I pull them out I might find the problem. The mechanic who put them in us Heavy Handed. Might be to to tight or cracked. OR there not plugged in all the way. OR BAD PLUGS FROM STORE. dam, I wish someone invented a quick way to check spark plugs.....I've heard it won't be the first time if it's the case.
Yep it is really easy to crack a plug these days if your not careful, you just need the touch to get it right.
coffeesolutionone18 answered 2 years ago
Well, about a week ago I wrote my Mercedes r350 was having spark plug issues . Changed my plugs and coils didn't help......I GOT FAITH. Maybe this will help someone who has similar problems with there r350. I THINK...... Might be wrong, but sometimes the car has a problem accepting new parts to SYNC with the older parts. I almost gave up! I went to Salinas/ Gilroy. 3 days ago, CAR RUNS GREAT! . but SERVICE D LIGHT IS ON. Anybody know how to clear it? Im not taking it in for 800$.!
