About three months ago, my sister’s ’99 Rav4 (188K) started exhibiting the following very noticeable performance issues:
She particularly noticed issues when stopped at red-lights: the car would shake and sputter, and she described it to me as though she thought it was “going to stall," to the point that she was not comfortable driving it. I drove it, and noticed this right away, just as she said. She said the behavior had just started with the last week or so. The engine was rather weak on hills and just generally not its "usual self".
I didn't have a lot of time to work on it, and so I was hoping that it was something simple….but those hopes were dashed when I pulled the first spark plug wire and saw oil all over it. I pulled the second and third, and those wires were dry. At last I pulled the fourth and it was completely DRENCHED in oil. The plugs in those two cylinders were soaked.
The most likely cause of this particular leak in our engines is a failure of the form-in-place-gasket (FIPG) material on the bottom threads of the spark plug tube. The bottom of the spark plug tube is threaded, just like the top. The whole tube screws into cylinder head, and since this part of the tube spends much of its life submerged in oil, the threads are sealed with a FIPG (rub-on gasket-maker) material. Over time and cycles, the material weakens and allows oil to flow into the spark plug tube and eventually onto the electrode, which causes misfiring and performance issues. The remedy for this oil leak is to remove the tube and re-seal the bottom threads with FIPG.
In order to access the bottom of the tubes, they must be removed. There is apparently Toyota SST somewhere in the universe which allows for the removal of the tubes without removing the valve cover, but I don't know how to obtain it.
I would love to have it, because it is unfortunate to have to replace a valve cover gasket that's not leaking. (Note: "valve cover" is often called "cylinder head cover" in Toyota documents.) Lacking the SST, the only other way is to completely remove the valve cover so you can turn the tubes out with a pipe wrench or two-nut method. Removal of the valve cover requires at minimum replacement of the valve cover gasket, but preferably replacement of the spark plug tube grommets, as well. The parts of are not expensive (about $25 - $30), but it does take more time.
About two months after completing this repair on my sister's Rav, I was checking the plugs on my own '00 Rav and noticed that a small amount of oil had reached the plug threads for my #1 cylinder. So, I got to do this job all over again on a different 3SFE. This DIY shows a mix of pictures from both jobs, in case you see differences.
The hardest part of this job is getting the bloody valve cover off due to the very tight confines. Having done this twice now, I think it is almost worth removing the throttle body to get that bracket out of the way, but I didn't want to deal with coolant so I didn't do this. I regretted that decision, though it is certainly possible to do without removing that bracket -- it just looks like it would be so much easier. If anyone knows of a better way of removing the valve cover, please add your experience here!
TOOLS:
- 5/8” spark plug socket
- 6” socket extension
- torque wrench with low side range to 13 ft-lbs
- 10mm, 12mm, 14mm sockets or wrenches
- 30mm socket
- pliers for hose clamps, etc
- pipe wrench (or channel-locks, or vice grips)
- much patience for removing the cover!
PARTS NEEDED:
- new valve cover gasket:
If you'd like to replace the PCV valve, this is a good time to do it. You will need the PCV valve (Toyota #12204-74030, $8.26) and the grommet (Toyota #90480-18001, $4.22). I replaced mine only because it hasn't been replaced and the grommet was in bad shape.
STEPS:
**The hardest part of this job is getting that dang cover off! Don't give up! (see the notes below)**
1.) Disconnect the negative side of the battery.
2.) Remove all the components noted in the picture, being sure to label all hoses and electrical to make re-installation quick and easy. They are: air filter and housing, engine hooks, accelerator link from the throttle body, power steering reservoir (pull it up off the bracket), and the plastic electrical housing by the timing belt cover. Also disconnect the hose from the PCV valve to the throttle body.
![Image]()
![Image]()
3.) Remove the spark plug wires (see this DIY) but do not remove the spark plugs yet. It is important to leave the plugs in to prevent things from falling into the cylinders.
4.) Use the 30 mm socket to remove the spark plug tube nuts. These nuts are what hold the cover in place. Don't be surprised if they are very loose.
![Image]()
![Image]()
5.) Remove the valve cover. Again, this is much easier said than done due to the tight constraints. You can use a screwdriver to pop the cover free on the corner, as show, just don't put the screwdriver into the gasket area. Once the cover pops free, you'll have to remove it by lifting it up along the path of the tubes, and that's the hard part because there is a bracket in the way on the driver's side and the timing belt cover and electrical housing on the passenger side. I found that moving the power steering reservoir and the plastic electrical housing by the timing belt cover UP and OVER towards the passenger side gave a little more room to work, but it is still very tight.
![Image]()
![Image]()
On the driver's side, there is a bracket for the throttle body that basically gives you no room to work. If you have a helper, have your helper lift the power steering reservoir and the electrical plastic cover thing up and over as much as possible, while you lift the valve cover up and over. If you don't have a helper, use zip ties/fishing line/whatever to tie all that stuff up and give yourself room on that end (passenger's side) of the valve cover. It is total pain, but it can be done. You'll have to do this all over again when you replace it, so keep track of what works.
6.) Set the valve cover and old gasket aside for the moment and clean the mating surface on the cylinder head. Carefully remove all of the old FIPG material, which you'll find in four places on each end. Remember these places because you'll be re-applying FIPG to these same locations later. Remove any bits of old gasket from the mating surface.
![Image]()
7.) Use the pipe wrench to remove the spark plug tubes. I understand that some people have used the "two-nut" method, but this didn't work for me; others said that they budged it with channel locks or vice grips. My grip is no where near adequate to budge these tubes using those tools! They are in there pretty tightly. I'm a medium sized woman, and it look a pipe wrench and quite a bit of steady force for me to budge these, but they will budge.
![Image]()
To remove them, turn counter-clockwise, as shown in the picture. Don't use any impact methods; use steady force and a good moment arm length. Mind the little metal bits that you'll produce using a pipe wrench, and protect the cam area with a towel and clean those little bits up with a magnet or whatever other method you use. You might wish to begin at the #4 cylinder end (driver's side) because you'll have more room to remove the others. Be careful removing the #1 tube because your tools may be very near the gear -- protect the teeth to prevent damaging them.
8.) Once removed, inspect and clean the spark plug tube. Remove all the only FIPG from the bottom threads. Don't apply the new FIPG until you are ready to re-install the tube. You might want to clean the area in the well around the spark plugs before replacing the tube because its easier to get in there without the tube.
![Image]()
![Image]()
9.) After cleaning the area around the spark plugs, you might wish to remove the plugs and clean further. If you do this, just be careful not to drop anything into the cylinders. Use the 5/8" spark plug socket to remove the plugs, and re-torque the plugs to 13 ft-lbs dry or 10 ft-lbs if you add anti-seize.
10.) Apply a new coat of FIPG to the threads of the spark plug tube, and re-install the tube. Be sure not to cross-thread as you are turning it. Turn the tube back in place rather tightly (I have no torque values to reference, but its tight!)
9.) Repeat the steps for the other spark plug tubes, if desired. You may wish to only re-seal the problem tube and leave the others be if they are not leaking. I decided to reseal all of them because I didn't want to have to do this again soon.
![Image]()
10.) Once the tubes are reseated, carefully clean and re-inspect the area for anything that shouldn't be in there, such as pieces of FIPG or metal bits. Remove the old gasket from the valve cover, and clean the gasket track well.
11.) Place the new gasket on the valve cover, and install the new PVC valve and grommet (if you're doing this). The PVC valve is metal and pulls out of the grommet by hand with force. The grommet will likely be very brittle -- try to remove it with a needle-nosed pliers to prevent pieces falling into the cover. Pull out any pieces that fall in before installing the new grommet and PCV valve.
![Image]()
12.) Once you are totally ready to re-install the valve cover, apply the FIPG to the areas shown in the picture below. There are four spots on each end of the head.
![Image]()
![Image]()
13.) With the new gasket in place on the valve cover and the FIPG applied, re-install the valve cover. You will again have to deal with the tight constraints, but hopefully it will be easier to put on than it was to remove. As far as I could tell, you have to get the driver's side end in first before dropping it in on the passenger's side. Its a pain.
14.) Once the valve cover is seated, install the new spark plug tube grommets. These grommets have a small tab on the perimeter, and this tab should be aligned as shown in the picture. If you are in a fix and must re-use your old grommets, replace them each to the same tube as you removed them.
![Image]()
![Image]()
15.) Install the tube nuts, only hand-tightening as you go. Using a torque wrench, alternate randomly between the four nuts to tighten them evenly to a final torque of 17 ft-lbs. Note: my older service manual has a typo showing an incorrect torque value. I have confirmed that the proper value is 17 ft-lbs.
16.) Re-install the spark plug wires and press them in firmly. Re-install the rest of the components.
Ideally, you would then let the FIPG cure for 24 hrs, but overnight curing should be adequate. Also, it is good idea to change your oil shortly after doing this repair to get any loosened material out of the system.
I hope this has been helpful -- please post tips on the valve cover removal if you have any!
1.) Misfiring, significant sluggishness;
2.) Shuttering, poor responsiveness.
2.) Shuttering, poor responsiveness.
She particularly noticed issues when stopped at red-lights: the car would shake and sputter, and she described it to me as though she thought it was “going to stall," to the point that she was not comfortable driving it. I drove it, and noticed this right away, just as she said. She said the behavior had just started with the last week or so. The engine was rather weak on hills and just generally not its "usual self".
I didn't have a lot of time to work on it, and so I was hoping that it was something simple….but those hopes were dashed when I pulled the first spark plug wire and saw oil all over it. I pulled the second and third, and those wires were dry. At last I pulled the fourth and it was completely DRENCHED in oil. The plugs in those two cylinders were soaked.
The most likely cause of this particular leak in our engines is a failure of the form-in-place-gasket (FIPG) material on the bottom threads of the spark plug tube. The bottom of the spark plug tube is threaded, just like the top. The whole tube screws into cylinder head, and since this part of the tube spends much of its life submerged in oil, the threads are sealed with a FIPG (rub-on gasket-maker) material. Over time and cycles, the material weakens and allows oil to flow into the spark plug tube and eventually onto the electrode, which causes misfiring and performance issues. The remedy for this oil leak is to remove the tube and re-seal the bottom threads with FIPG.
In order to access the bottom of the tubes, they must be removed. There is apparently Toyota SST somewhere in the universe which allows for the removal of the tubes without removing the valve cover, but I don't know how to obtain it.
I would love to have it, because it is unfortunate to have to replace a valve cover gasket that's not leaking. (Note: "valve cover" is often called "cylinder head cover" in Toyota documents.) Lacking the SST, the only other way is to completely remove the valve cover so you can turn the tubes out with a pipe wrench or two-nut method. Removal of the valve cover requires at minimum replacement of the valve cover gasket, but preferably replacement of the spark plug tube grommets, as well. The parts of are not expensive (about $25 - $30), but it does take more time.
About two months after completing this repair on my sister's Rav, I was checking the plugs on my own '00 Rav and noticed that a small amount of oil had reached the plug threads for my #1 cylinder. So, I got to do this job all over again on a different 3SFE. This DIY shows a mix of pictures from both jobs, in case you see differences.
The hardest part of this job is getting the bloody valve cover off due to the very tight confines. Having done this twice now, I think it is almost worth removing the throttle body to get that bracket out of the way, but I didn't want to deal with coolant so I didn't do this. I regretted that decision, though it is certainly possible to do without removing that bracket -- it just looks like it would be so much easier. If anyone knows of a better way of removing the valve cover, please add your experience here!
TOOLS:
- 5/8” spark plug socket
- 6” socket extension
- torque wrench with low side range to 13 ft-lbs
- 10mm, 12mm, 14mm sockets or wrenches
- 30mm socket
- pliers for hose clamps, etc
- pipe wrench (or channel-locks, or vice grips)
- much patience for removing the cover!
PARTS NEEDED:
- new valve cover gasket:
(Toyota part #11213-74020, $13.61 at localpartsstore.com)
- four new spark plug tube grommets: (Toyota part #90480-30025, $4.14 each at localpartsstore.com)
(Note: I had time to order the Toyota parts for my '00 because it was a planned repair, but my sister's '99 was an emergency repair, so I had to go with the Felpro kit from Advance Auto. The kit was about $25 and came with the valve cover gasket and 4 grommets, and everything seemed to be of high quality, and to work well; there have been no issues with the Felpro kit)
- FIPG, "form-in-place-gasket", aka "gasket-maker": (I used Permatex Ultra Black because I was in a pinch, but the Toyota FIPG is part #00295-00103; I think Permatex Ultra Black is a good substitute)
- new ignition wires: (you only need new wires if you either have never replaced yours, or they are contaminated with oil. Many in this forum and myself recommend the NGK wires)
- new spark plugs:(many in this forum and myself recommend Denso PK20TR11 Double Platinum; don't use Bosch)
If you'd like to replace the PCV valve, this is a good time to do it. You will need the PCV valve (Toyota #12204-74030, $8.26) and the grommet (Toyota #90480-18001, $4.22). I replaced mine only because it hasn't been replaced and the grommet was in bad shape.
STEPS:
**The hardest part of this job is getting that dang cover off! Don't give up! (see the notes below)**
1.) Disconnect the negative side of the battery.
2.) Remove all the components noted in the picture, being sure to label all hoses and electrical to make re-installation quick and easy. They are: air filter and housing, engine hooks, accelerator link from the throttle body, power steering reservoir (pull it up off the bracket), and the plastic electrical housing by the timing belt cover. Also disconnect the hose from the PCV valve to the throttle body.
3.) Remove the spark plug wires (see this DIY) but do not remove the spark plugs yet. It is important to leave the plugs in to prevent things from falling into the cylinders.
4.) Use the 30 mm socket to remove the spark plug tube nuts. These nuts are what hold the cover in place. Don't be surprised if they are very loose.
5.) Remove the valve cover. Again, this is much easier said than done due to the tight constraints. You can use a screwdriver to pop the cover free on the corner, as show, just don't put the screwdriver into the gasket area. Once the cover pops free, you'll have to remove it by lifting it up along the path of the tubes, and that's the hard part because there is a bracket in the way on the driver's side and the timing belt cover and electrical housing on the passenger side. I found that moving the power steering reservoir and the plastic electrical housing by the timing belt cover UP and OVER towards the passenger side gave a little more room to work, but it is still very tight.
On the driver's side, there is a bracket for the throttle body that basically gives you no room to work. If you have a helper, have your helper lift the power steering reservoir and the electrical plastic cover thing up and over as much as possible, while you lift the valve cover up and over. If you don't have a helper, use zip ties/fishing line/whatever to tie all that stuff up and give yourself room on that end (passenger's side) of the valve cover. It is total pain, but it can be done. You'll have to do this all over again when you replace it, so keep track of what works.
6.) Set the valve cover and old gasket aside for the moment and clean the mating surface on the cylinder head. Carefully remove all of the old FIPG material, which you'll find in four places on each end. Remember these places because you'll be re-applying FIPG to these same locations later. Remove any bits of old gasket from the mating surface.
7.) Use the pipe wrench to remove the spark plug tubes. I understand that some people have used the "two-nut" method, but this didn't work for me; others said that they budged it with channel locks or vice grips. My grip is no where near adequate to budge these tubes using those tools! They are in there pretty tightly. I'm a medium sized woman, and it look a pipe wrench and quite a bit of steady force for me to budge these, but they will budge.
To remove them, turn counter-clockwise, as shown in the picture. Don't use any impact methods; use steady force and a good moment arm length. Mind the little metal bits that you'll produce using a pipe wrench, and protect the cam area with a towel and clean those little bits up with a magnet or whatever other method you use. You might wish to begin at the #4 cylinder end (driver's side) because you'll have more room to remove the others. Be careful removing the #1 tube because your tools may be very near the gear -- protect the teeth to prevent damaging them.
8.) Once removed, inspect and clean the spark plug tube. Remove all the only FIPG from the bottom threads. Don't apply the new FIPG until you are ready to re-install the tube. You might want to clean the area in the well around the spark plugs before replacing the tube because its easier to get in there without the tube.
9.) After cleaning the area around the spark plugs, you might wish to remove the plugs and clean further. If you do this, just be careful not to drop anything into the cylinders. Use the 5/8" spark plug socket to remove the plugs, and re-torque the plugs to 13 ft-lbs dry or 10 ft-lbs if you add anti-seize.
10.) Apply a new coat of FIPG to the threads of the spark plug tube, and re-install the tube. Be sure not to cross-thread as you are turning it. Turn the tube back in place rather tightly (I have no torque values to reference, but its tight!)
9.) Repeat the steps for the other spark plug tubes, if desired. You may wish to only re-seal the problem tube and leave the others be if they are not leaking. I decided to reseal all of them because I didn't want to have to do this again soon.
10.) Once the tubes are reseated, carefully clean and re-inspect the area for anything that shouldn't be in there, such as pieces of FIPG or metal bits. Remove the old gasket from the valve cover, and clean the gasket track well.
11.) Place the new gasket on the valve cover, and install the new PVC valve and grommet (if you're doing this). The PVC valve is metal and pulls out of the grommet by hand with force. The grommet will likely be very brittle -- try to remove it with a needle-nosed pliers to prevent pieces falling into the cover. Pull out any pieces that fall in before installing the new grommet and PCV valve.
12.) Once you are totally ready to re-install the valve cover, apply the FIPG to the areas shown in the picture below. There are four spots on each end of the head.
13.) With the new gasket in place on the valve cover and the FIPG applied, re-install the valve cover. You will again have to deal with the tight constraints, but hopefully it will be easier to put on than it was to remove. As far as I could tell, you have to get the driver's side end in first before dropping it in on the passenger's side. Its a pain.
14.) Once the valve cover is seated, install the new spark plug tube grommets. These grommets have a small tab on the perimeter, and this tab should be aligned as shown in the picture. If you are in a fix and must re-use your old grommets, replace them each to the same tube as you removed them.
15.) Install the tube nuts, only hand-tightening as you go. Using a torque wrench, alternate randomly between the four nuts to tighten them evenly to a final torque of 17 ft-lbs. Note: my older service manual has a typo showing an incorrect torque value. I have confirmed that the proper value is 17 ft-lbs.
16.) Re-install the spark plug wires and press them in firmly. Re-install the rest of the components.
Ideally, you would then let the FIPG cure for 24 hrs, but overnight curing should be adequate. Also, it is good idea to change your oil shortly after doing this repair to get any loosened material out of the system.
I hope this has been helpful -- please post tips on the valve cover removal if you have any!
