BajaRunner

Yes I have... I have also made sure that there is spark going to each cylinder with a timing light. Also with the misfire I haven't seen the timing light ever miss either, making me to think that ignition components are OK, but I really don't know.

HighLux

a weak spark can light a timing light up. make sure they are clicking onto the plugs really good...and to the cap. sometimes we just pop the boot on the plug and think we have it...but mine need a good hard push then they click on.

BajaRunner

Yeah i mean I've tested the resistances across the coil/igniter as well as the resistances across the wires. I've got NAPA distributor cap and rotor but the misfire was there before I changed them. The resistance across the primary igniter was a little high but only by a half of ohm.

Can anyone tell me if a worn timing chain could cause this problem?

Also I have posted the pictures of the rocker arms and cam shaft... any opinion on those?

Another issue which can be causing my erratic idle is that the coolant level in the radiator always seems low. Once it warms up, it will go to regular height. If I try and add coolant, it just flushes into the overflow tank. Its sort of pissing me off. I don't understand why. If its cold in the morning, I'll open the radiator cap and will just see the radiator core with no coolant.

ANOTHER symptom I have been forgetting... The TICK TICK TICK noise... I've adjusted valves 3 times now... But the TICK TICK TICK sounds like its coming strongest from the upper portion of the exhaust. I'm 95% sure its not an exhaust leak, its sounding like its INSIDE the exhaust system...sticky/burnt valve?! Crap I donno I am just throwing out everything...Pre ignition?

skypilot

iTrader: (1)

we are on opposite sides of the country so writing is all we have. Try putting in that Marvel Mystery oil in the tank. I use that Lucas fuel additive, since that seems to work too. Then go do some full throttle hill climbs or something where you can really mash on the gas. I like long hill climbs in third so the engine just maxes out for a couple of minutes. Something maybe sticking and yep maybe its an exhaust valve or a bad / soft cam lobe worn away. If you want to pull the cover and walk the engine over look for a worn cam lobe or rocker possibly even a mushroomed valve stem. And if its covered in sludge several cans of fuel cleaner maybe required. My favorite that you cannot get anymore is GM fuel injector cleaner aka pure naptha, stuff will strip furnature!

My 22re has an annoying valve tap for years and nothing ever comes of it, it just keeps ticking away like an annoying watch. Now it needs a clyinder head due to rust so I am done with it, 3mgte incoming.

TNRabbit

Injectors tick louder than anything on this engine except a fuel pulsation damper going bad. Use a mechanic's stethoscope to pinpoint the noise.

BajaRunner

Skypilot: On the first page of this thread, I have some photos of the rockers. Everything is very clean and new looking except for the #3 and #4 exhaust rockers which look like they've been running hot. Also, I have a cam lobe that looks to be worn slightly. Not sure if it would be enough to cause a misfire though. Especially since the misfire only comes on when it goes into closed loop!!!


Rabbit: I've tried and tried, but will try again I know what the valve tap sounds like. This tap gets LOUDER with engine temperature.

skypilot

iTrader: (1)

I do not like 3 & 4 rockers at all. The dirt should be even all across the engine, not layered, caked or chipped. that tells me the cam faces are getting hot and coking the oil. Which means an oil flow problem on the back end of the engine. If you pull the rocker arms, you have to do a head gasket because the seal breaks. its not a 100% thing but better safe than sorry.

The wear pattern on three looks shot. I bet it has a ridge on it. If the rockers & cam were on my race car it would be in the scrap pile. And yes it would cause a misfire due to valve timing being off "all the time". in this case poor clyinder exhaust purge screwing up the A/F ratio, and a failure to ignite or only partially "hit".

I wonder if your cly head is cracked or corroded away in the exhaust port like mine are.

My engine has a valve tap due to that kind of wear and you cannot adjust it out, its just toast. So I am planning an engine swap instead of a rebuild. At 330k there is not much worth saving.

BajaRunner

Hmm interesting. I understand what your saying.

Now would that cause a drop in compression or not? Because I am getting steady compression. Or would it only be visible with a leak down test?

What pisses me off is that these components are supposedly only 5k miles old. They must have done an improper break in.

For me, It seems like it would be easier to just swap cam and rockers (and head gasket).

skypilot

iTrader: (1)

No you would not see it on a compression or leak down test, since nothing is "leaking", and a compression test does not tell the whole story. The valve is not "lifting high enough & long enough" for a complete "as designed" purge due to wear on the cam and the rocker arm. You might say it has different "lift and duration" than the other three clyinders. It is possible the valve on three is "bent" a little from a meeting due to being one tooth off during installation. Four maybe just had a little less contact, while one and two escaped. You have to pull the head or use a pressure hose the hold the valve "up" to take off the lock and spring off three and see if it moves or sticks. A leak down test "might" pick up a bent valve stem. If its sticking that explains the cam wear. I think Kings or someone can regrind yours if its Japanese.

My thinking is a cheap Chinese cam and rockers were installed, along with a plugged rocker shaft (insuffcient oil flow)

BajaRunner

Interesting...here's what I've gathered from what you've said, and it seems to make sense:

1)The cam isn't pushing (opening) the exhaust valve enough to let out all the exhaust, and thus throwing off the mixture of that cylinder(s).
2)The O2 sensor isn't reading it because it's slight, and only in 1 or 2 cylinders.
3)It runs better in open loop because its dumping fuel and overcompensating the lean mixture.
4) This would explain why there is a lot of noise coming from the engine

Soo... stock cams aren't that expensive. I've read its a good idea to replace all the rocker arms when changing a cam. They don't seem overly expensive as well. Are the rockers aluminum?

Pull the head, send to machine shop for warpage and valve job and then I could swap in a new cam and rockers. Hows that sound? ;/

The only thing that doesn't add up is the fact the spark plugs look good. Could it be that slight? ALso I dont know if you listened to my video's? Did you get anything from them?


(Listen to the end where you can really hear the miss)

BajaRunner

Great. Truck overheated on the way to school. I just had put in a 180F Toyota thermostat. It was going close to the red...not all the way into it though luckily.

I keep thinking my head gasket is blown but I have no loss of coolant and my oil has no coolant in it. However, I get major backpressure when I try and burp the system. If I open the cap up and revv the engine, it spouts out bubbles and coolant everywhere.

Looks like I might have to just pull the head and do the gasket, cam and rockers.

skypilot

iTrader: (1)

I bet your head is shot. The factory heads are notorius for corrosion putting holes into the exhaust ports and pressurizing the cooling system. No way to repair them, you have to buy a new head. this however does not affect how the engine runs, it just blows anti-freeze out the tail pipe. At night when cold the cooling system is still "pressurized" not a vacuum to draw makeup coolant from the bottle on the RH side.


http://cgi.ebay.com/ebaymotors/Toyot...Q5fAccessories

This another problem I have on mine.

I think that repair 5k miles ago was just a gasket change, to buy a little more time.

I checked "Kings" and it was $419 for a new head with valves & springs, cam, rockers, and head gasket. A reground cam was another $105. So shop around.

Mine has not had a timing chain replaced in 330k miles so I would add that $80 timing kit too.

It really starts adding up to overhaul a high milage engine. Thats why I am just riding mine into the ground. When it blows I will put in one of those JDM dual OHC 3mgte inline 6 clyinder turbo engines in mine with a conversion bell housing and a wiring patch. I looked at the LC Engineering crate engines and decided junkyard engines were a much better deal. 22re engines are quite common and prices for one with under 100k are resonable. If you bust your hump you can do the swap in a weekend. 10 hours R&R transmissions and figure another 8 to swap the engine out ( straight lift w/ no trans).

Check around your local junk yards, there should be alot of serviceable engines around cheap, since cars for clunkers primarily hit v8 F150's. I just see no reason to sink hard earned money into it when there may be a cheaper option.

myyota

If your getting bubbles and excessive presure out of the radiator with the cap off, and you said it over heated, chances are that you have a blown head gasket. Check out engine builder for a new head and cam.

norcal93

Seems basic, but did you test the thermostat to be working properly, and did it get installed correctly?

Sorry to hear the injectors didn't help, at least you ruled it out, as it looked like they needed to be done.

84foyota

Sorry I've been away on business and not following your thread....Actually amazed you have not yet found the source of your problems yet.

Looking back at your spark plug pics I detect a slight rich mixture on #4. Slight as it is this should indicate the problem cylinder or the one that is missing.

Sounds like you have since had a overheating issue so it could be a blown head gasket. Initial leakage between the two rear cylinders could cause the symptoms you have detailed. I am not sure of the status of your engine at this point but you better have that checked out.

My original thought based on your description of the problem is a valve that is not seating properly. This will also cause your reported symptoms and would also cause some uneven wear on the respective cam lobe as the valve will often not follow the contour of the cam or will be tight in the guide and will cause "Scuffing" or chattering on the cam lobe.

Sounds to me like you have a mechanical problem with #4 or #3 cylinder. Do a wet and dry compression test. That should tell you what’s going on. If you can't do that, check the valve clearances as this will often give you a clue to the condition of the valves and seats. If you have one or more that are too tight or way too loose you have an issue. Since the lifters are adjustable also check to see were in the adjustment they are set. If one is backed way off or tighened down more then the others then someone has adjusted for the wear in the valve at some point which will mask the problem but not cure the miss fire.

BajaRunner

Just a quick reply for now... But would I really need to get a new head even though the one I have is only 5k old?

Say that the head gasket was blown...Would it really warp the head past being serviceable? Is it really necessary to get a brand new head?

The symptoms I have for having a blown head gasket is the high pressure within the coolant, obviously a bad idle and lack of power. However, I have no loss of coolant and my oil is fine. (I just drained it this weekend). I also have steady compression. I do have a white/gray smoke only in the morning, it doesn't blow the whole time. What other tests I could perform to find out of my head is blown?

This was the first long drive I have taken since the injector replacement. I've never had an overheating problem before. I'm wondering if I got some air stuck in the system still. I have always had a hard time trying to burp this system... Like I said, it just spews out.

myyota

Ive heard there is some kind of test you can do to see if there is exhaust in the coolant, im sure someone here knows more about this, if so more info on this would help.

HighLux

If you revved the engine with the cap off ....and it blew coolant out....you have a bad head gasket. End of story.

skypilot

iTrader: (1)

It depends, deck the head, two new valves and guides, rocker arms & cam. I have a feeling its a lot cheaper to get a head swap from a reputable source. Who do you know? besides this way its waiting for you, not the other way around.

Was the timing chain done? Supposed to be done every 100k, so you may need that too. I bet there is crud in the pan as well that needs to be cleaned out.

I think a junkyard or auto salvage yard engine might be the way to go. Might not be right for you. Head, pan, and chain have been done before without pulling the engine. You would not be the first if chose that route. How much can you do alone?

BajaRunner

Well, it didn't overheat on the way home. I think it might have been that I had air in the system from taking off the throttle body....But yes, I'm not convinced either way that I have a blown gasket or not.

I took it by a Toyota specialist shop, and the guy seemed nice and knowledgeable. He listened to the truck and thought its definitely cam related...especially since it was aftermarket. The fact that it only had 160 psi in the cylinders he felt that there was valve float, especially at high idle when I got the miss.

I forgot to mention to him that it wont miss when its in open loop. He feels that I should go ahead and just change the cam out with a stock cam...