Coasting drag

[supertrooper9]

Hello all. I'm not sure if this is an actual problem but I wanted to understand the concept a little better.

I recently got an '05 T4R Sport Edition and sometimes I let it coast when no cars are behind me. Given the weight of the vehicle, it really doesn't surprise me how much speed it lets up after I take my foot off the gas. My older Camry can coast forever it seems like but that's a light car.

So the 4Runner slows comparatively quicker, but something weird I'm noticing is this sudden tug (you can feel it) a few seconds after I stop pressing the gas and/or when the vehicle goes below a certain speed. It literally feels like I just stepped on the brakes when I'm doing no such thing and the speed just plummets. It doesn't stop the car but can make it go from 30 to 20mph in like 5 seconds. It makes it impossible to try to coast to a red light when it gives out so easily and there are annoyed drivers behind me. This is all on flat terrain, no hills in the least bit where I live.

Am I experiencing something unusual or is this a normal, common "issue"? I'm no auto expert so sometimes I just don't get why stuff happens. Thanks for your help

 

[Clemsonfan15]

Funny you mention this. I drove my future Aunt's 4runner last week and noticed the same problem. I didn't know if it was normal either.

My 3rd Gen doesn't do it.

 

[eskimochaos]

Nevermind

 

[morphius909]

I believe Grade Logic is the term that you use when you experience that...but that's when it's going down a hill.

 

[supertrooper9]

Gotcha...although the concept seems kinda counter-productive to me cuz it won't let you coast. Thanks Morphius.

 

[nated05]

I have had this same issue starting within the last few weeks. It feels like the "normal" downshift when you are coasting down a hill, but now it happens pretty much whenever I let up the gas. The only reason this could become more of an annoyance is if it hurts my gas mileage. The next time I fill up I will have to calculate and see.

I wonder if disconnecting the neg. battery cable to reset the ECU will help.

 

[VaWoodpecker]

I have had this same issue starting within the last few weeks. It feels like the "normal" downshift when you are coasting down a hill, but now it happens pretty much whenever I let up the gas. The only reason this could become more of an annoyance is if it hurts my gas mileage. The next time I fill up I will have to calculate and see.

I wonder if disconnecting the neg. battery cable to reset the ECU will help.

If you want to try that all you have to do is: go into the fuse box by the battery, remove the fuses labeled 10A ETCS and 20A EFI for a few minutes (vehicle off, key off). When you go to to restart the truck turn the key on, count to 10 then turn to the start position or it may sputter and stall on the first attempt.

That will keep you from having to reset the windows, radio, etc. and will do the same thing.

I had bad mileage after extended trailer towing, and this fixed her right up. Take it easy as it relearns driving patterns for the next 100 miles or so.