qskillet

I am a newbie to car mechanics, so please forgive my lack of proper terminology.

I have a 1999 Toyota 4runner SR5 v6 4WD. 249000 miles. My 3rd cylinder has been misfiring on warm starts only. (It does not happen if I let it sit for more than 90 minutes after driving it).

I took it to the local Toyota dealer after it the check engine light starting occasionally flashing on an off. They told me it was a bad engine coil and I should replace the spark plug. So I had them replace both.
The next day the misfires starting happening again, so I took it back to Toyota. They tested the compression, and said I had low compression in cylinder 3. They also did a leak test on the cylinder and said it was not leaking.
I asked them why it was only occasionally misfiring, they said my engine was slowly dying, and I would have to rebuild or buy a new one to fix it.

Does this sound right?

Thanks,

MacusWayne

Check for hydrocarbons in the coolant with a block tester, NAPA still sells them i believe. Toyota designed the 22re with only 10 bolts for the head, arranged like this :o:o:o:o: , which forces #2 and #3 cylinders to share the six bolts in the center. Stretched bolts and a leaking head gasket are the result. Testing for Hydrocarbons in the coolant is the fastest way to check for a leaking head gasket. Im not saying that this is the exact problem, but with 249k miles it's worth checking. Best of luck man.

rworegon

Macus, the OPs 1999 v6 is certainly not a 22re. Geesh.

OP, are you using any coolant or oil? How does the coolant and oil look?

qskillet

@rworegon-

Oil was changed just under 2000 miles ago. It still looks clean (checked via dipstick). Coolant in the reservoir looks good (light red and clear). Pulled the cap off of the radiator and the coolant inside (from what I could see) looks the same.

rworegon

How long does the misfire last on re-start?

Have you pulled the spark plug, say a half hour after driving, and looked for anything i.e. fuel, coolant, oil in that cylinder?

Sometimes an injector can leak fuel into the cylinder or coolant can seep in after shut down causing a misfire at re-start.

qskillet

@rworegon-

Misfire will last pretty much the whole time I am driving. I have not pulled the spark plug after driving. Ill do that next time and take a close look at the cylinder.

MacusWayne

My apologies, didnt notice til after i posted.

rworegon

...you can go back and edit your own prior post.

qskillet

I noticed that when I had the coils unplugged the lip (not sure what it is called) on cylinder 3 was
much dirtier then 1 and 5 (picture below). Could this be due to leakage from the injector?

rworegon

No, that is not from a leaky injector. It looks like oil that got past the oil seal that sits on the backside of the valve cover and slips down over the edge of the tube you see. Or, at one time the spark plug was very loose letting exhaust/oil past it.

qskillet

Pulled the spark plug on cylinder 3 after driving with misfires. I did not see anything visible on the plug. And just to verify I pulled the spark plug from cylinder 1 as well to compare, and both spark plugs looked the same.

rworegon

Are you getting a CEL? Take a look down those spark plug tubes after it sits a bit and see if anything looks amiss.

By cylinder 3, you are meaning the middle cylinder on the passenger side with the coil sitting on it, correct?

5 6
3 4
1 2
Front of engine

Similar misfire issue on another forum:
http://www.ultimateyota.com/index.ph...&topic=10264.0
http://www.ultimateyota.com/index.ph...&topic=10294.0

rworegon

Take a look at all the vacuum hoses and be sure they are tight with no splits. Also, the air intake flexible rubber tube.

Hopefully, someone chimes in with an idea why it only seems to happens when it's warm.

qskillet

Yes Sir, the middle cylinder on the passenger side. As far as the tubes, everything looks like it should. And yes, I still get the blinking cel about half the time when it is misfiring.

Thanks for pointing me to the other forums, I appreciate it. Was already thinking about looking at the fuel injector. Ill check out the hosing as you suggested.

Texas_Ace

If compression is low then that is either valves or rings. Seeing as a leakdown came up ok rings is the more likely the cause, also makes more sense if misfiring.

Are you using any oil? What kind of oil are you running?

Stay away from that dealer, they don't have a clue what they are doing. If the coil was the problem then you would also get a misfire on cylinder 4 IIRC as the same coil fires both. Also the way you test the coil is to simply swap it with another one and see if the problem follows it. They robbed you on that one.

I would start out with the basics, complete tuneup first off. I would start off with a seafoam treatment, it works wonders on my engines. I have a writeup I made awhile back I will post in the next post with more details.

I would get a few bottles of random injector cleaner and put it in the gas, in case the injectors are the problem.

Then get some seafoam and marvel mystery oil. Put a quart of the mystery oil in your oil and about half a can of seafoam. Drive the truck normally for a few days to a week to let it work.

Run the seafoam cleaning process in the next post at this point.

Then change the oil, when you refill it use mobile 1, since it is winter you want something a little thinner then normal. Mobile 1 has a lot of cleaners in it to help clean out the engine.

Use another quart of marvel mystery oil when you are refilling the oil, as per the instructions on the bottle. Then toss in 1/3 a can of seafoam into the oil as well if you really want to clean out the engine.

Get yourself a good oil filter, AMSoil EA series (must be ordered online) or mobile 1 (most parts stores have it). Get an oil filter for a mid 90's ford taurus 3.0l V6 oil filter. It is larger then the stock filter but otherwise the same. You will want the extra media when cleaning out an old engine like this. If it works properly the oil will get real dirty real fast as it cleans out the engine.

After that I would change the Plugs all the way around if they didn't replace them all. Plug wires, air filter, fuel filter ect. A good tuneup.

Then drive the truck for ~1000 miles before changing the oil again. The oil will get dirty quick remember. After that I would run another compression test to see if anything improved, you can test it yourself, no need for a dealer. Be sure to do a before test as well so you have some base numbers. A tester is worth the money, only around $30.

Depending on what the new numbers are, you can decide if you just want to run mobile one or do another treatment of marvel oil.

Here is a post where I talk about my first hand experience with this treatment on my own truck.: https://www.yotatech.com/52001993-post287.html

Took my compression from all over the place to 205psi across the board!

That is where I would start, you have nothing to loose at this point.

Texas_Ace

First off I am NOT responsible for anything you do to your car, this is just what works for me.

Well, just figured I would post up some results with these products. Many of you have seen me promote seafoam in the gas and intake manifold before and i am a huge fan of this but i have never really suggested running it in the oil.

Well my motor has had 3 weak cylinders with low compression ever since i got the truck. Generally got around ~180psi on the good cylinders and ~135-145psi on the bad ones.

I had figured it was stuck rings but never really thought about trying to free them up. Well I was going to change my oil and saw a can of seafoam and marvel mystery oil sitting on the shelf. Figured what the heck, might as well try them. If the motor blows i will rebuild it.

So I put them in and drove the truck for a day or 2 to let them work. I then ran 2 gallons of water through the engine with my meth injection kit and then used the rest of the seafoam in the intake manifold like normal.

After all of that I changed the oil and drove it for a few days. I noticed an immediate improvement in how it ran. Lot smoother, started easier and just felt like it had better compression.

Yesterday I decided to do another compression test to see if my instincts were right. To my amazement the compression had jumped up to 190-195psi across the board! Ran the test twice cause i could not believe it.

So I have to say that done with caution I am now a believer in using these in the oil. I would not do it on a healthy/clean/new motor but when you got nothing to loose or you know there is a problem that these might help it is worth a shot.

Like usual i highly recommend the seafoam through the intake and in the gas as well.

Now for the methanol injection. I have to say it really will clean out the motor, i pulled the supercharger a few months back and it was sparkling clean inside all the intake manifold ports. It really will help clean everything out over time.

I will give you an idea on the treatment i give all new-to-me cars when i first get them besides a complete tune up.

First off Get all the stuff you will need together:

1 to 3 cans of seafoam
1 bottle of marvel mystery oil
oil change parts for your car ,filter, oil ect.
gallon of distilled water/washer fluid
Few random bottles of injector cleaner, i like to overload on that when i do it.

You can also pick and chose what parts of the treatment are right for you. You could leave out the water treatment if you wanted, it takes a lot of time. Putting the seafoam/marvel mystery oil into your oil can work great. It freed up the rings on my 4runner and bumped compression from what was ~180psi on 3 cylinders and ~135-145psi on the other 3 to an even 190-195 across the board. It does have a bigger chance of possibly hurting something then the rest of the treatments though. EDIT: I put another quart of MMO in the oil with my last oil change, after running another compression test when changing the oil recently My compression Is up again to 205psi across the board! New OEM spec is ~220psi!

Now I will first dump all the injector cleaners into a gas tank about 1/4-1/2 full. If you are going to put the seafoam/marvel mystery oil into your oil this is the time to do it as well. I do advise caution with putting these things into your oil, I have had great luck with it personally but there is a chance they could hurt something. I would not use it on a new/clean/otherwise great condition motor. On an older motor that you don't care that much about go for it.

I put a quart of MMO and ~1/3-1/2 a can of seafoam into the oil a few days before I plan to change the oil. Then drive the truck like normal until you change it to let them work. I have put them in the oil with a fresh oil change and ran then for 3000 miles with no ill effects so no need to worry, this is recommended on the bottles.

Then I like to start with the water/washer fluid first. Find a vacuum line on or near the Throttle Body that will feed all the cylinders evenly. Make sure it is not only connected to 1 intake runner or offset on the intake manifold so it would only feed some of the cylinders. If that is your only option you need to find an equal port on the other side of the manifold.

You don't want the line to be too big. If it is too big you can get a smaller vacuum line and usually shove it into the bigger line and it will seal good enough for what we need. 1/4" line (the line is generally measured by the outside diameter, the internal orifice is generally around ~1/8” or slightly larger) is a good size, slightly bigger or smaller is fine as well.

Now start the engine and drive it around to get it nice and hot. When you get back connect the vacuum line to the port you found earlier and stick it into the gallon of water. Important, you want the engine to suck the fluid in, DO NOT pour the fluid in. You will have to give the engine a lot of gas to keep it running but just let it keep sucking it down. You want to try to keep the RPM’s above ~2500-3000rpm during this process. Don’t leave it at idle, this is usually very simple once everything is setup. I usually run the whole gallon through the car in 2 or 3 treatments, broken up by me beating the heck out of it before coming back for the next one. You want to keep the engine hot for it to work.

After you finish the water go drive the car hard to clean it out. Don’t worry if it feels a little down on power, this process can foul the spark plugs which is why it is a good idea to install new ones when you finish. Or get some el cheapo Copper plugs to temporarily use during this process. Don’t swap plugs until completely done with the seafoam as well.

Now time for the seafoam, this is like the water except you need to let the car sit between treatments. Just like the water hook up the vacuum line and get ready to rev the motor up to keep it running, doesn’t need to be quite as high for this since you don’t want the seafoam to go right through, you want it to stick to everything so it can clean it. Stick the vacuum line into the can of seafoam and try to keep the motor running till it sucks up about half the can for the first treatment. Then let it bog out and die. Now let it sit for half an hour or so. Longer is better, for the first few treatments though you don't really want to let the motor get all the way cold.

Now go out and restart the car, it will take a little bit to restart, put the gas to the floor while trying to start it tends to help. Once started you should have one heck of a smoke show. The more smoke, the dirtier the engine is. You can let it idle for a little bit and have fun revving it so you smoke out the neighborhood or go for a drive and leave long trails of smoke. At some point go out and flog the car before the next treatment.

Now repeat the earlier process except use about 1/3 of a bottle at a time from now on so it lasts longer. Keep doing this a few times, you will start to notice that you have less and less smoke the more treatments you do. It will get to a point where the amount of smoke stops improving, thats when it is about as clean as it will get right now.

I generally will do one last treatment at this point, heavier this time. I will then let it sit overnight.

Dump any leftover seafoam or marvel mystery oil into the gas tank at this point.

The next morning start it up and go for a nice long drive, get the oil up to temp and keep it there for a good 10-15 mins if possible to help clean the last of the junk out of the motor. Could go to work and do it when you get home or whatever. Just don't put that many miles on it before changing the oil.

Now change the oil, and make SURE you change the oil, after all of this you will have some water and seafoam in the oil for sure, it needs to be changed. Refill the oil check all the fluids and there you go. It should now run noticeably better.

I have had GREAT luck with this regime on all of my cars but you do this at your own risk!

If you really want to clean out everything you can also get a "motorvac" treatment done. It is a snap on machine that will run cleaner though your fuel system to clean out the injectors and combustion chambers. It lacks some of the cleaning of the above treatments but it cleans other things better.

If you are scared of the above treatments this is a GREAT option. I noticed my vacuum jump from -20inhg to -22inhg after having the motorvac done, not that unlike the above treatment but like i said they clean things a little differently. Doing both would be ideal but a motorvac treatment will run you about $100.

qskillet

@Texas_Ace

I took your advice (thanks by the way) and added some MMO and Seafoam to the oil and the gas tank. Then seafoamed the engine. Man did she smoke. Must have been really dirty. Ill drive it for a bit then change the oil. Ill let you know how it goes.

Texas_Ace

Good luck, hopefully it is something simple.

Reset the ECU after you change the oil to clear any codes. Just pull the battery cable for a little while and try to start the truck while it is disconnected to drain any leftover power.

qskillet

Update:
Sea foam and Mystery oil works wonders. Although I have not checked my pressure (don't have the tools), my hesitation is pretty much gone. I sea foamed the engine one more time than changed the oil. It was pretty dirty when I changed it. I am thinking Texas_Ace was right in thinking it was the rings. I probably need to replace them soon, but as of now, she is working pretty good. @ Texas_Ace ECU reset its self, and has not come back on since. Thanks for the advice.

Texas_Ace

Glad to hear it is helping! I would not jump right to tearing into the engine. Keep running the MMO in the oil on a constant basis and putting the seafoam into the oil ~100 miles or so before the oil change. Then keep doing the seafoam treatment with the oil changes.

Be sure to keep a close eye on your oil, it will continue to get dirty much faster then normal. Check the oil when you drain it and adjust your change interval accordingly. Starting at ~1000-1500miles.

In my case it took about a year for this regiment to really work, my compression improved even more my last oil change a few weeks ago. I am now back up to almost OEM specs and running good as new. So it is very possible that you can salvage the engine and not need to do anything to it for quite some time.

Also, reset the ECU anyways even if the CEL disappeared. You want to reset the maps after these treatments.