C289 misfires after 30 minutes.
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1999 c280 Sport
C289 misfires after 30 minutes.
1999 C280 Sport with 185k miles. Recently the car has developed a predictable misfire after about 30 minutes of drivetime. It runs fine from a cold start. Nice smooth acceleration even under load such as climbing a hill. However, after about 30 minutes it will misfire with it becoming very noticeable under acceleration or hill climbing. Check engine light will usually light at this point. Pulling codes I get a cylinder 5 misfire always joined by cylinder 1 on occasion.
This misfire problem initially occurred several months ago but more sporadically and usually turning off the car and restarting solved the issue. The plugs were replaced a year ago and I changed the coil packs on 1 and 5 after the initial misfire occurrence. It ran mostly error free until this latest development which is now a constant issue after the 30 minute drivetime. And this one doesn’t resolve by turning off and restarting. Any suggestions?
This misfire problem initially occurred several months ago but more sporadically and usually turning off the car and restarting solved the issue. The plugs were replaced a year ago and I changed the coil packs on 1 and 5 after the initial misfire occurrence. It ran mostly error free until this latest development which is now a constant issue after the 30 minute drivetime. And this one doesn’t resolve by turning off and restarting. Any suggestions?
