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View Full Version : 4Runner cylinder 6 Iisues?



arch007bak
10-27-2011, 04:05 AM
I have to start by saying I know enough about vehicles to know that I don't know squat about vehicles other than driving them. I'm a little alarmed about the number of threads I've read on here about 4Runner cylinder 6 problems.

10 days or so ago on a Saturday eve, my '05 4Runner (V6, 167,000 mi) started rough like it was missing. Took it to O'Reilly to have it scanned and they said it was a misfire on cylinder 6...probably an ignition coil. Couldn't get it in to the shop until Thursday but the O'Reilly guy said it wouldn't hurt to drive for a few days. Thursday, dealer near my office (30 miles from home) said the same thing...ignition coil but they had to order it and made appointment for the next Monday. Friday before that, drove 30 miles to a meeting and it started to overheat. Took it in Monday (overheating at the end of that 30 miles) and told them about the overheating. Left it there with them and the next thing I know I'm being told it's a blown head gasket and I need a new engine ($7,000 for a used one and around $10,000 for a new one). Said they knew it by blowing air into the cylinder and it bubbled up in the radiator and also said they had to add 1 gal. of coolant. They didn't take it apart to check if the cylinder was bent/warped/whatever or even to see if the gasket was ruined.

Brought it back to the dealer where I bought it. They tell me they see no evidence of a blown head gasket, the ignition coil isn't bad and that all I needed was new spark plugs because I have the platinum kind that hadn't been changed...ever. Also told me you can't test my engine by blowing air into it to see if it bubbles in the radiator.

PLEASE tell me, is the first dealer lying to me to get to buy a new vehicle or is the second one not checking far enough? I'd think if the second one was trying to get me to buy a new one, they would've told me the same thing...

cam-shaft
10-27-2011, 05:22 AM
If your shop is blowing compressed air into #6 cylinder and the coolant is bubbling at the bottle or radiator then you have an internal leak unfortunatly. The coolant passages of a motor should no way mix with the combustion chamber. Plus if you are over-heating and have to add coolant and have a bad plug well that is a result of coolant getting into the combustion chamber of the motor, water will not compress and can lead to bent rods and more if problem not repaired. Yes your plug may be bad but it sounds like the result of some other problems. Have your coolant system psi checked.
Hope this helps thanks, Cam-shaft.

pearlj10
10-27-2011, 05:24 AM
First, this situation sucks. I am sorry. Second, I am no expert. Third, I would never trust the O' Reilly scan although they are certainly helpful as a first level diagnostic. Fourth, the dealer with a engine replacement scenario sounds entirely specious. If your truck was 1 gallon low on coolant that would be atrocious. Have you checked the coolant yet? Is it already low? If so, you may have a serious problem. I don't know what to say other than try to find a reputable toyota mechanic. Is your truck leaking coolant when it is parked? Did you change the spark plugs yet? If not, try that before getting serious about the other issues. Maybe pull the plugs yourself and photo each one to post here for confirmation. Hope it works out alright...

arch007bak
10-27-2011, 05:34 AM
I told the 2nd dealer (where I bought it) to go ahead and change the plugs and left it with them for a couple days so they could drive it for a bit (their suggestion). Going back there tomorrow AM to talk to them again to make sure they checked the head gasket the 1st dealer said was blown.

arch007bak
10-27-2011, 05:36 AM
Can a blown head gasket really lead to needing a new engine after barely driving it? I keep seeing these threads about that cylinder 6 and saw a few that said their VSC lights all came on at the same time...which mine did too.

Applejack
10-27-2011, 11:23 AM
A blown head gasket= a whole new engine???? I would doubt that. A new head perhaps, if it was severely warped and could not be machined. Did you notice massive amounts of steam coming from your exhaust?? This would indeed indicate that coolant has entered your combustion chamber.

keezer37
10-27-2011, 11:56 AM
-The dealership can put a camera in the spark plug hole and look for evidence of coolant leaking.
-They can pressurized the cooling system via the radiator fill to see if it holds pressure or pushes coolant into the cylinder. (Assuming you have no other leaks.)
-They can check the national data base (can't remember the name) to look for prior incidences of this issue.
-First dealer was full of it because they could have verified the ignition coil by swapping it with one from another cylinder. This would have caused the scanned fault code to indicate the swapped to cylinder were it the coil.

Listen carefully to what the service writer/mechanic has to say. Ask what checks they did without offering any info. Get them talking. I'd say something like, "For this kind of money, you're gonna need to explain thoroughly just what is going on here". You don't need to know about mechanics to tell truth from fiction. When the individual no longer makes sense, he's blowing smoke. Make them educate you. Note: Service Writers usually lack any in depth knowledge.

-You were overheating because so much air was passing over the coolant temp sensor instead of coolant.
-Understand that a major portion of the cost of replacing the head gasket is in the labor (getting to the head gasket). So they cannot take anything apart to physically check the gasket.
Start on page EM-149 thru EM-157 and you can see what it takes to get to the head gasket: http://www.ncttora.com/fsm/05+/data/ileaf/06toyrm/06toypdf/06rmsrc/rm2006ta/00701110.pdf
This for the Tacoma, but it's the same engine.

I didn't let the dealership do my work because I thought I was being lied to. I wish Toyota would/could exercise more control over their dealers. It's their good name.

CA-RJ
10-27-2011, 05:56 PM
A used engine can be found for much less. Less than $2,000 in fact. PM me if you need help locating one.

zolo
10-27-2011, 07:11 PM
Ok, I'm no expert but I own a shop in GA with another guy. 2 mechanics me and Him. We are honest as the day is long. We both drive Toyota's. Him an 07 FJ me an 06 Tacoma. www.decaturgarage.com
If your 05 V6 4runner has a blown head gasket it would be the first Ive heard of one blowing. They are one of the best V6s Toyota has built. Not to say they will never fail or cant fail but thet are great engines. We have worked on many 4runners, Tacoma's, and FJ's and have not seen one with a blown head gasket.
There are 2 main types on blown head gaskets.
1-if the coolant and oil mix in the crank case.
2-if the coolant leaks into the combustion chamber.
We have seen both on many different types of engines. There are many ways to check. As stated before in this thread. The coolant system needs to be pressurized to the PSI on the radiator cap, maybe a bit more. In a great system the pressure will hold all day. If your pressurized coolant system does not hold at all and there is no external leak then it is entirely possible the head gasket is blown.

History will show that the #6 cylinder is the most common to blow on the older Toyota engines. But you have a fairly new truck.

I would not replace your original engine. You say it was not overheated to bad. If that's the case the internal engine parts are likely fine. If the head gasket is blown just fix it. Have the head machined and move on. I would go so far as to say maybe consider fixing just the one side, depending on mileage and condition. But I rarely recommend that. If the intake is off and its torn down that far go ahead and do both sides.

Do not trust the Toyota dealers. They are just that dealers. Its a business and they have no loyalty to the customer the way the customers have to the Brand. Ive seen it to many times. The dealers telling customers things that are simply not true.

If you want an honest estimate of repair I will be happy to put one together so you know what you should be paying. I am not asking for your business we are so far apart just so you know I would do it cause your on Expo and I have the cost prices and estimate systems to do this.
Let me know.

But first have a quality mechanic make sure it is blown.
cheers,Daniel

arch007bak
10-28-2011, 02:14 AM
Thanks for all the input guys - very helpful. 2nd dealer (the one I bought it from and who's done nearly all the regular maintenance) took care of the spark plugs and everything points to not having a blown head gasket and definitely no need for a new engine. They also switched the ignition coil to another cylinder like Keezer above said and no indication of misfire. Read several other places about the signs of the coolant leak (milky white oil, burnt coolant smell on spark plugs, etc.) that make me think the 1st dealer was either incompetent or lying to me thinking I'd be desperate to buy a new one from them.

cpayne5
11-01-2011, 07:44 PM
Thanks for all the input guys - very helpful. 2nd dealer (the one I bought it from and who's done nearly all the regular maintenance) took care of the spark plugs and everything points to not having a blown head gasket and definitely no need for a new engine. They also switched the ignition coil to another cylinder like Keezer above said and no indication of misfire. Read several other places about the signs of the coolant leak (milky white oil, burnt coolant smell on spark plugs, etc.) that make me think the 1st dealer was either incompetent or lying to me thinking I'd be desperate to buy a new one from them.

I had similar symptoms (misfire and VSC lights, water noise in the dash, and slowly dropping coolant level); though I noticed it way way before I had lost a gallon of coolant. I attributed (hoped!) it to old plugs at first, too, so I threw in some new plugs. All was good, for a few days (my guess is the new plugs were masking the effects). Then I got another misfire. Turned out to be my head gasket. My 4Runner (2005) has 90k miles on it.

For what it's worth, I repaired my own vehicle and put about $700 (gasket kit and a few other may-as-well-replace-while-I've-got-everything-apart pieces) into it.

I would have the second shop perform the pressure tests, if I were you. The first shop said they did, which led to their HG diagnosis. If the second shop finds the same thing, you've got your answer. Not to sound grim, but I'm guessing it's a HG, from what I've heard here.

keezer37
11-01-2011, 10:01 PM
At a minimum, continue to monitor the situation:
-Listen for gurgling when starting out first thing. (Air passing thru the heater core)
-Three to five seconds of rough idling at cold start up in the morning. (Misfiring plug. It has to misfire a few times to pop a code.)
-Check coolant level in the morning when the engine is cold.
-After returning from driving five or more miles when you are sure the engine is thoroughly warmed (so the radiator cap lifts, beyond 186 deg.), prior to shutting the engine off, pop the hood and look at your coolant reservoir. If you see bubbles, you've got a blown gasket. Nothing else can cause this. Check this a few times.

java
11-02-2011, 06:21 AM
there have been a couple blown head gaskets that i have seen in the 4th gen runners online, im sure there are more that dont post to forums. a pressure test should pretty definately tell you.