Hi everyone, I’m looking for some advice on what to do with my 2012 RAV4 4WD that has 102k miles. I’m currently experiencing issues with my RPM and driving. When starting the car up, the RPM will shoot to 2500 and slowly work down to between 1500-2000, but no lower. When I put the car into drive/reverse the RPM will drop to ~800 which seems to be right - but when put specifically into drive the car will speed up to 35MPH on its own. I feel like I’m constantly pressing on the brake so that I’m not speeding up too much when city driving. Another issue that I’m facing is that when I’m slowing down to a stop, as the RPM gets to right about 1000, it will then jump back up to 1500 very quickly causing the car to lurch forwards. The final symptom I’m noticing is that when I’m driving at 30mph or faster and shift into neutral, the rpms will oscillate between 1000 and 2000 going back and forth. I have gotten my MAF sensor replaced two times already - causing the problem to be very temporarily fixed but not lasting even the drive home. I have also cleaned my throttle body which also had temporary relief but soon went bad again. I have done a lot of searching online and many fingers point to the IACV, which is my next hope to get replaced, but I’m looking for any advice from anyone that has had a similar experience or has any recommendations!
The electronic throttle body controls the engines RPM’s from signals it gets from the computer.
One thing to try is have the throttle body cleaned. And if that doesn’t work then it’s going require some diagnostics.
In your case for example, a faulty coolant temp sensor could be telling the computer the engine coolant is at -20 degrees which would cause the idle to be too high.
But what needs to be done is have scanner connected to the vehicle so its operating parameters can be monitored.
Tester
Why was the MAF replaced? Presumably you’ve had a check engine light on, and it was scanned for codes? We “speak” code here - so give a full report.
The advice is to not just replace stuff on guesses. If you’re handy, you can pretty easily, and very cheaply clean your own throttle body (mentioned by Tester above). And it it has an IACV (which it might not as most (all?) cars with electronic throttle bodies don’t need one), those can also be cleaned easily and cheaply.
Is your check engine light on? Have it scanned for codes and post the exact codes here.
Thanks for the response! I haven’t had any check engine light on - and the mechanics that I took it to chose to replace the MAF sensor. The car is on warranty so luckily it’s not going to cost me but yeah I’m not a huge fan of replacing things that don’t need it.
I’ve cleaned the throttle body after removing it from my car, surprisingly there wasn’t much carbon build up at all. I believe there is an IACV on my specific model - and am taking it into the shop on Thursday (hopefully third time’s the charm!) to see what they think one more time.
Thanks for the response Tester! I did clean the throttle body which gave temporary relief from the high rpm issue - but I’ll check out the diagnostic to see if there’s anything that comes up on that end!
If you look your vehicle up at Rock Auto, it doesn’t list an IAC valve for your vehicle.
Tester
You are right - I made the big mistake of initially trusting google about it being there. 
It does all sound like a wonky throttle body.
Hopefully the shop you’re going to has Toyota Techstream scanning capability, or its equivalent. There can be error codes stored that don’t turn on a check engine light.
Any shop/scanner can tell you what the ECU thinks the coolant temp is - which is also something to check and is simple.
No rav4 experience just knucklehead diyer, but when my corolla had similar symptom , turned out to be a faulty idle air control. Concur w/CR above, try to find an experienced shop having the toyota techstream tool.
Hi CR,
The mechanics replaced by throttle body and unfortunately it didn’t help my startup RPM any bit, nor the lurching into stops when driving. I’m still working on finding a scanner that has toyota techstream data to figure something out as well. Do you have any other ideas as to what could be causing these issues with the RPM being far too high?
Thanks!
Hopefully they just cleaned the throttle body? That’s an easy/reasonably cheap maintenance item. Replacement without something like error codes and testing is a little extreme.
See @Tester’s first post about the coolant temp sensor. But for gosh sakes, don’t have it replaced without having someone check it first. This is easy with even the most basic/generic scanners.
If you want the techstream scanner capabilities go search around on Toyota-dedicated forums. There are…well, ways around having the genuine article.
I’ve heard the Toyota dealer might have it… lol
I am going to get real here, so it may hurt a little…
You are going to have to find a real shop with real diagnostic mechanics with rear diagnostic equipment - pro level scanners…
Of course, someone that has invested $5,6,7K+ dollars in a scanner and software will charge for the diagnostic… Wait a minute, this all sounds familiar somehow, oh yeah, Tester said it in the 2nd post/1st reply, and then a few more times by others in different ways…
Or at least start with a really good DIYer scanner and look at Live Data to see what is out of whack…
Have you looked for a Toyota/Lexus specialty shop… They might be able to find the issue in a short time and end up saving you in the long run with replacing the correct part and not just guessing, as to what might be…
IF this is a warranty thing and it is something that could be dangerous, then I would pay to have it properly checked out and or fixed and take the bill to them, you might be out some money, but you would be safe…
Your choice, keep playing with amateurs and risk getting hurt, or go play with the real pros and get it repaired correctly and quickly (most of the time)…
It’s been 3 days now and you still haven’t mentioned if the coolant temp sensor reading is correct or not, it was mentioned in the 1st reply and again later…
A compromise might be to hire a pro shop to diagnose the most likely cause for you, and then you diy’er their suggested parts replacement. Suggest the first step however is to verify the coolant temp sensor is producing accurate data. That’s something most diy’er can do themselves, with a relatively inexpensive scan tool
Just hair-brained, no-nothing, diyer with no RAV 4 experience. None at all. I do own and diy’er r/m an older Corolla.
Hey Dave,
Don’t worry about hurting my feelings… I’m here looking for advice and am glad to take it honestly. Like I had said in a prior reply - I am still looking for a place local to me that has that Toyota Techstream Diagnostics system and will go to it once I’m able, I’ve not had the time to do it. I’m not planning on going back to the ‘warranty’ mechanic, so the plan is to find a real pro as you would put it and get the information I need. Thank you for the response!
FWIW, the temp sensor doesn’t require a techstream. And many shops have very powerful scanners that could likely do the job. The Techstream is just Toyota’s proprietary thing with 100% capabilities. It likely means a dealer, and taking a non-warranty car to a dealer can be a little nuts.