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I have a 1997 Rav with automatic transmission and 4wd. When going at around 60-70mph with my foot slightly on the gas my engine is revving between 2500 and 3000rpm. When I take my foot completely off of the gas pedal the rpms drop by only about 200 or so, and I seem to slow a bit more than it seems I should (it is especially apparent when driving downhill). Is this normal? Is the automatic transmission supposed to "drop-out" of gear when you take your foot off the gas so that you can coast freely? Or is it supposed to stay in gear? When at a full stop the car idles around 600rpm (right at the top of the bottom few lines that are close together in the gauge).

I realize that when overdrive is off and or the transmission is in either 2nd or "L" that this kind of behavior is normal, but when I'm driving at 65mph and I take my foot off of the pedal and I feel like my transmission is slowing me down (engine braking) it seems a little strange to me.

I recently had my transmission fluid flushed. (Within the past few months, because I recently bought the car)

I ask this question in conjunction with a long and arduous process of troubleshooting bad gas mileage.
 

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Hello again. This sounds interesting. First, your idle sounds perfect, at 600rpm. So do not worry about this. But the 'drop out' issue sounds strange. I think, and I will have to check, that if I lift my foot off the gas the engine speed drops all the way down and I coast. I remember this because coming from a manual transmission to an automatic in the Rav freaked me out the first time when this happened.

BUT, I have only just got this Rav and 1) have not used the ECT power button much (is yours on?); 2) have not switched the overdrive off; and, 3) rarely drive above 55mph.

So, I have not covered all the possible coasting scenarios which could explain why this is happening e.g. perhaps RAVs do not coast in power mode? I dunno.

On a happier note, you actually get engine breaking while coasting downhill on the 4.2s, so you could call this a hidden-extra!!
 
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Well I may have hit a jackpot (maybe, don't want to make any judgements prematurely). So I've basically tried everything to get better gas mileage. Then this afternoon I was reading about resetting the ECU. I had tried to pull the ECU fuse for about 10 seconds several months ago and it didn't seem to make any difference.

Then I saw on another topic that you need to disconnect to positive terminal on the battery for a few minutes in order to reset the ECU. So, just to be safe, I disconnected both terminals on the battery and let it sit for half an hour. I got in the car and it felt like I had just injected it with hormones or something. I had to lay on the brakes to hold her back. Handled very differently, and the now it seems to "coast" a lot easier (my question and potential problem mentioned above). It doesn't feel like the engine is holding the car back anymore. Then I noticed the fuel gauge leaped up to full after it had previously indicated only 3/4 full (after only 33 miles on the trip odometer, mind you, that's how bad of gas mileage I have been getting.)

I haven't taken her out on the highway yet or for a drive longer than 15 minutes, but so far things are looking good. I'll post my status after some more extensive tests at freeway speeds and after this tank of gas. Good grief, do I hope that I hit the nail on the head with this one. If it's a big dissappointment and nothing I did made any difference at all I'll be sure to post those results too.
:?
 

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No, I got it wrong (again). Took the Rav for a nice long drive at 55mph. Took my foot off the gas and the revs dropped only by 200rpm or so, not to the 600rpm idle speed. So it does not coast or freewheel, which means you have no problems here.
 
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Thanks for testing the way your idle functions and reporting back. Much apreciated.

Well, I have now driven nearly 150 miles on this latest tank of gas and the gauge is reading 2/3 full. I have most definitely at least doubled my gas mileage after disconnecting the battery for a while in order to reset the ECU. Literally, at least doubled my gas mileage. I will post further and more detailed results after I finish up this tank of gas and do some calculations and comparisons.
 
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I have been through a few tanks after resetting the ECU and now have some things to gab about. Immediately after I reset the ECU the car ran like a dream. It obviously had more power, and when felt like it coasted "freely." The difference in performance was obvious both on the freeway and in the city. The first few gas tanks I averaged around 20mpg, however; nearly identical to what I had been getting before. It seems my fuel gauge was fooling me.

Last week, however, the obvious gains in performance disappeared. I would not be surprised at all if it was the "41st" start after I had reset te ECU (they log 40 driving cycles, don't they?). Now it is once again sluggish. It feels like it's struggling going 65, and in the west's wide-open spaces I need to go at least 75 to keep up with traffic. It seems I get worse mileage on the freeway than in the city.

It feels like there is something which is not disengaging and is increasing drag and friction in the drivetrain. I'm not sure if it's the transmission, or if it is the differential, or transfer case. . . or who knows what? Any ideas on this? I remember reading on some web site about a guy who's friend had a RAV getting lousy fuel mileage and they discovered the "something something" :) wasn't disengaging. Hahaha. I don't know if that sparks ideas in anyone at all. I'm determined to fix this gas mileage problem.
 

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I want you to know that you are not alone in these fuel mileage concerns, I have tried everything possible to increase my mileage and the best I can get is about 20 - 22 MPG.,I have replaced alot of parts, all but the O2 sensor, which is a little expensive for me.I do recall someone in the forum mentioned that because it is AWD., it kicks in alot more than we think it does, and to turn all wheels it will take alot more fuel. I really do like my Rav4, But I would do anything to get somebetter mileage. there are guys on here with the same year and model who tell us their getting between 27 - 30 MPG.I just want to know why, and how,, anyways Good luck, and keep us posted,, thanks,,,Joe,,,
 

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Personally, I've found that the lack of low-end torque and the eager-to-upshift, reluctant-to-downshift transmission can make the vehicle feel sluggish -- in top gear at lower rpms, a situation you find yourself in often, the engine doesn't make enough torque to provide any useful power. You're out on the highway at a constant speed and the car starts to slow down, so you look around and realise that you're ascending a barely perceptible grade, but it's more than the engine can handle.

You add more gas but nothing happens until you step way down, and only then does it downshift. This results in a fuel economy hit since you can't be as light on the throttle in this car as you'd like. Even keeping up with traffic can require a relatively heavy foot. Pushing the ECT button in helps it feel more responsive around town, but again, it does use more fuel.

That said, I find I get 19-20 mpg around town, on short trips, in the winter. On the highway, add 2-3 mpg. In the summer, both city and highway trips improve, to the 22-23 and 25-27 mpg range respectively.
 

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Hopefully, it is not news to you that you didn't get a performance vehicle.

That being said, make sure the car is in a decent state of tune. Plugs, air filters, and lubes should all be up to the task.

I got a very slight bump in MPG by changing out my ATF and Differential fluid with Amsoil Synthetic products. Slightly smoother ride and shifting as well. Of course, the stuff I replaced was in the car since new over 100,000 miles ago.
 
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BUMP! anyone find out any causes of the bad fuel economy?
I have the same problem as 'scriabin'

Sucks gas bigtime 16L/100km (15mpg) I also feel the drivetrain bogging :(

sick of this. but at least the car is not driven much.
 
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Ya know, one thing taht I wonder about is the compression in the cylinders. I added some of that "compression restoring" oil additive stuff, and the Rav ran smoother for a little while. Course, that is also when I was experimenting with different gas grades, and ran 89 octane instead of 87 (seemed to run smoother, but the gain was minimal and not worth the price difference). BUt as an engine ages, the compression in the cylinder gets thrown out of whack. This can lead to adverse performance and assumadely lesser gas mileage. Has anyone checked the compression on their cylinders and had it adjusted back to spec?
 
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