RPM dropping when I hit bumps in my 4Runner?

[2StepsAhead]

Been having a very intermittent issue in my 4Runner, its a 2005 V8 and sometimes it will stall out when Im coasting really slow and hit a big bump. Doesnt matter the octane or amount of gas...now today I was coasting on the highway at about 60 and watching the rpms, itll stay at 1,000-1,1000 on the highway and when I hit a bump itll dip to 500 for a second and then come back up. I replaced plugs, seafoamed, cleaned the maf and tightened down the battery stay/terminals...hasnt fixed it. Any ideas?

[STL_G8GT]

I can see it now... doing 30mph on the highway, staring at the rpm gauge, people honking flying by you...

"screw off, I'm diagnosing!"

[2StepsAhead]

LOL, its better than when I try and make it stall going over bumps through a turn and everything cuts out, wrestling the wheel with no power steering and trying to restart it haha.

[hivoltagedriver]

Did you fix this? Try smacking the MAF with the handle of a screwdriver while the car is idling in park and see if it stumbles. Bad MAF maybe?

[TailG8er]

Check fuel pressure when this happens, could be a funky pump or electrical connection.

[2StepsAhead]

Think I got it, I started cleaning the maf and checking the wires...nothing. Changed plugs, nothing. Seafoamed, idle got stronger but still it would dip on the highway. Cleaned my throttle body and havent been able to make it stall yet or drop while coasting on the highway, dont want to jinx myself yet though so Im going to see what happens.