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Discussion Starter #1
OK Radio fixed, now on to the real problem!!

1999 rav4 4x4. Just got this car, and it lacks power going up the slight's hill. It runs real smooth, with no hesitation, just lacks any kind of power! Checked the air filter, and put in a new fuel filter, which looked like it didn't need to be replaced. Checked the plugs and they are white as a ghost, so, it is running really lean! What are all the things that would make it run so lean?? A few thoughts. A clogged CAT, Mass flow sensor, would either of these cause a real lean condition? BTW, where is the Mass air flow sensor located, it's not in the air intake hose going into the throttle body. Pics would be awesome! The check engine light is not on, and it has no codes pending. Thanks for your thoughts on this!
 

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1999 rav4 4x4. Just got this car, and it lacks power going up the slight's hill.
Welcome to the 3S-FE in a relatively heavy vehicle. OK acceleration off the line, but nothing for passing, especially for the AWD version (my FWD version got better MPG too).

So may be nothing "wrong." Weight reduction would help, but what's to remove? Or just live with it understanding that it's a great, usually very reliable, quirky-looking grocery-getter.
 

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1999 Toyota RAV4 with 3MZ-FE 6 cylinder engine, camo wrap, OME lift, heavily modded
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Have you checked for any codes on your OBDII, there are several things it could be:







It can also be a problem with vacuum leaks and fuel injectors.

Don't just start removing and replacing, do some diagnostics
 
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Discussion Starter #4
Thanks Gator. The videos were informative! I don't have a lot of money, so I would like to check and eliminate everything I can, before spending any money on it! Where is the Mass air flow sensor located, so I can clean it? There seems to be no schrader valve, so how do I check fuel pressure, and how do I check fuel injectors? If the CAT is clogged, would the 02 sensor right in front of it read rich, and lean out the fuel mixture? Just to be clear, there are no OBD2 codes set and none pending. The spark plugs are about as white as if they were new out of the box, but they have been in the car for over 6 months. It's clearly running really lean!!
 

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White, leaning toward grey are not a bad thing.
Deposits are a bad thing.
 

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Discussion Starter #6
You're not hearing me!!! Look at the whitest spot on your screen right now! That's how white they are, all 4 of them!!!! It's running way to lean!!!
 

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Discussion Starter #7
I just noticed, my thread was moved from the 4.1 General section to here! Who did that and why??????
 

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I just noticed, my thread was moved from the 4.1 General section to here! Who did that and why??????
I'm sure one of our moderators moved it, because loss of power is a mechanical problem, so it belongs in the faults and fixes forum.
 

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Discussion Starter #9
It would seem to me that faults and fixes would be for OBD2 fault codes, and most people would not be viewing that section unless there car had the check engine light on. My car has no Fault codes set off. I would think more people would view my problem in the general section!! THOUGHTS!
 

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It would seem to me that faults and fixes would be for OBD2 fault codes, and most people would not be viewing that section unless there car had the check engine light on. My car has no Fault codes set off. I would think more people would view my problem in the general section!! THOUGHTS!
Long, long ago when The Old Ones built this place, they decided to have 4 forums devoted to the RAV4, General, Accessories, Faults & Fixes, and finally TSB's. The description for the Faults & Fixes forum reads: Got a problem with your RAV4.1? Share it here and maybe even find a solution. To me, a loss of power sounds like a problem. The General section reads: Discuss anything RAV4.1 related that doesn't fit in the categories below. So if you're talking about how the RAV4 handles, or the graceful curves of the body styling, or what color looks best, those discussions would be for the General forum. When I took over as Admin, I wanted to change those forums to be like the others, Mechanical, Interior, Exterior, and TSB, but that would mean poring over every thread to decide where it should go. Accessories would have interior accessories like speakers, exterior accessories like fog lamps, and engine accessories like custom intakes. Trying to sort out that mess just didn't seem worth the trouble.
 

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1999 Toyota RAV4 with 3MZ-FE 6 cylinder engine, camo wrap, OME lift, heavily modded
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If you look through the faults and fixes section you will find the answers to a lot of issues. The bad part is when someone asks for help, several people give them help and they never post back saying what finally resolved their problem or which way they decided to go on a particular issue. You may have to get creative in your searches, because one person's hood is the next person's bonnet.

So what I'm saying is to be courteous and post responses. It could be years latter that someone sees your thread and says, "that's it, that's my same problem," only to find there was never a final solution, bummer, been there several times myself.
 

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There is no mass air flow sensor on a 99 RAV4. "Lacks power" can mean a lot of things. These lacked power when new. They have enough. Down shift and punch it. I suppose it would be helpful to compare yours to someone else's. Do you lack power for a stock 99 RAV4 or do you have normal power? Normal ain't much, remember.

Now, if you want power, well, add boost. I have plenty of power now. Not an easy swap. The swap was relatively painless, but the wiring is a nightmare. Still, I'm running around 250 HP now with the boost controller dialed back. Boost starts to come on a 2K RPM. I don't have to down shift on hills anymore.
 

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I'm sure one of our moderators moved it, because loss of power is a mechanical problem, so it belongs in the faults and fixes forum.
I moved your post ASA I saw it for the exact reasons JuneBug gave. OBDII codes are just a subset of the faults a 4.1 could have. I'm quite sure you've gotten more responses here than in General which isn't specific enough IMO to elicit as much interest.
 

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Discussion Starter #14
O K, I understand now. It's just in the past, at other forums, the General section is where everyone would post there problems.

DR, Hess What is this boost you're talking about?

I still think there's a problem, I should be able to do more then 50 MPH up a slight grade on the free way. Even if I down shift, it doesn't help much! The plugs should not be that white, A good plug should be a light Coffey brown. I'm old school, and cut my teeth on a 65 Mustang! In those days you didn't have a computer adjusting everything, You just ran it hard, pulled out the plugs, and checked the color. The color of the plug would tell you if it was rich or lean! Then you would know what you were looking for! Lean usually meant air flow or fuel problems, and Rich meat electrical problems! Sometime you just needed to adjust the size of the jets in the carb, and you were go to go!!

And yes Gator, I agree with you, people need to post the end solution to there problem! It would save people a lot of time and headache!!
 

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BOOST: Turbo or supercharger. Like the 3SGTE motor from a Caldina that I have.

It's difficult to say with a low powered vehicle. With a 3SFE, it's like you're saying "My low powered vehicle is low of power." If you're running it at 5K RPM in 3rd gear, do you still have problems? This ain't a Mustang. You need to rev the crap out of it to get anything. Also, unlike a Mustang, you won't hurt it by doing so.

If there are no codes, try some Sea Foam to clean out the fuel system. Check the compression. Do a leak down.
 

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Discussion Starter #16
Just so you know it's and automatic. When I take it out of over drive, and it's in 3rd gear, it won't rev over 3500 or so! If I push it all the way to the floor, it will drop down into 2nd, and rev way up, but you can't be driving on the free way in second gear. It's either not getting enough gas or somethings clogged.

When I get a chance, I'll do the compression test and post the results! What should the compression be on this car???
 

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Not sure on the spec. Mostly look for the cylinders to be close to each other.

Also note that the auto trans version of these is said to be very slow.
 

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Another quick test is to do a few 0-60mph runs. Just start from 0 and floor it on a level road. Let it rev and shift on its own. Do it both ways to rule out wind benefit. Normal would be 10 seconds, maybe 11. Much slower = issues.
 

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Discussion Starter #19
I did some test!

Vacuum Test: At idle, 18 lbs and held steady. Revved it to 2500 and snapped it back. Went right down to 0 lbs and then right up to 22 lbs and leveled back out at 18 lbs. So, all is good with the vacuum test!

Compression Test: All plugs out, and at running temp. 185 lbs across the board. That seems really high!

Does anyone know what the compression should be at on this vehicle, and what could make it so high??
 

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I'd say 185 lbs is very good especially since there's no variation.

My 0-60 test pretty much checks everything. It's the one I run on every used car I test drive, usually for friends.
 
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