My Volvo S40 has a message that says reduced engine performance. It idled rough for a minute but ran fine after that. I've changed the spark plugs because it was past time, but the new ones that I got from AutoZone only have one tip and the old ones had three. now it is running worse than before. Could the spark plugs make it run worse? AutoZone scanned the car and said it was the fuel rail pressure sensor. I have one on order now.
My car has 160000 miles.
My car has a manual transmission.
Hi there. When it comes to spark plugs, it’s always a good idea to stick with the Original Equipment Manufacturer or OEM replacement; especially on modern cars, trucks and SUV’s. The tri-tipped spark plug - pioneered by E-3 Spark Plugs are very efficient and have been proven to burn more fuel in the combustion chamber on the average than single tipped spark plugs. However, it’s not a significant difference as to cause a reduction in engine performance. The faulty fuel rail is most likely the source of your Volvo’s problems. I would recommend making that change first and seeing if the performance clears up first. If it does not, switching back to the OEM spark plugs might be beneficial for you.
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