Morning! When driving up an off ramp or crossing the delaware river on the Betsy Ross, around 1500 rpm and roughly 40-45 mph, the motor stumbles for a quick second or two. Just changed the fuel filter and cleaned the K-N. Plugs were done at 85,000 and there is 103,000 on it now. Any help is appreciated. Thanx

 

If you just cleaned the K&N filter, starty by cleaning the MAF (mass air flow sensor). the oil from the K&N can get on the MAF and cause it to malfunction. Need to use electronic cleaner or CRC makes a cleaner for the MAF. I'm assuming the CEL (check engine light) is not lit; if so you need to get the code(s).

 

Yes, clean the MAF and how long since the fuel filter was changed?

Opps, reread and see it was 18,000 miles. It should be ok, but I change mine every 15,000. If you got some fuel with water in it, could be the filter.

 

Thanx for the help. Going outside right now. I'll be back for more advice. Thank You guys both!!

 

It could be a low grade misfire due to one or more weak coils - or use of non-Motorcraft plugs - or failure to use dielectric grease.