TRDCal
New member
Not to hit you'll while your down but if your pedal shakes when you pressed it, thats because your rotors are warped and will need to be replaced
P0306 Misfire Rough Idle
- Thread starter airforceabbott
- Start date
Not to hit you'll while your down but if your pedal shakes when you pressed it, thats because your rotors are warped and will need to be replaced
Check engine light P306
I just had this happen to me. I replaced all the spark plugs, swapped coils and even used FI cleaner, it all worked temporarily. The 3rd time the light came on I took it to the dealer, they told me cyl 6 had coolant in the cylinder and that it would be $2500 to take it apart and put it back together, that's if there weren't any other problems. When they got the heads off the heads were good but they recommended a valve job +$500, and they needed to replace a bunch of fasteners that broke in the process. Once they got it all back together one of the O2 sensors $200 was bad due to the engine burning coolant. All totaled, with a new water pump $200, timing chain $800, & valve job, it totaled $4800. Think very seriously if you want to keep your ride, hopefully I'll get another 111k miles now.
I just had this happen to me. I replaced all the spark plugs, swapped coils and even used FI cleaner, it all worked temporarily. The 3rd time the light came on I took it to the dealer, they told me cyl 6 had coolant in the cylinder and that it would be $2500 to take it apart and put it back together, that's if there weren't any other problems. When they got the heads off the heads were good but they recommended a valve job +$500, and they needed to replace a bunch of fasteners that broke in the process. Once they got it all back together one of the O2 sensors $200 was bad due to the engine burning coolant. All totaled, with a new water pump $200, timing chain $800, & valve job, it totaled $4800. Think very seriously if you want to keep your ride, hopefully I'll get another 111k miles now.
TRDCal
New member
You probably could have installed a rebuilt engine for that price. Sounds like you wanted to go the extra mile to have a like new condition engine, or your dealership took advantage of you. But for people who need to do this in the future and are on a budget, it can be done for less.
Man... same thing has been happening to me for the past week and a half. I have a 04 Limited V6 with 169K miles.
I first noticed a small shake right at startup, but it would go away after about 15 seconds. I thought there was some condensation in the gas tank, so I filled up with premium, put in some Sea Foam, and made sure the gas cap was nice and tight. A couple days later, the CEL went on. Read the codes and it was a P0306.
I took it to a shop I trust on Saturday and they switched out the coil in cylinder 6, changed all spark plugs, and cleaned the fuel injectors. $350 later, I hoped the issue was gone, but the CEL came back on today. I still notice a slight shake on startup. Just pulled the codes for the CEL and it's a P0306 again.
So should I recommend my tech to look at the HG? I haven't noticed any usual signs of an HG going bad, but from what I've read, it appears that it could be. Any other suggestions before I take the 4Runner back in early next week?
I first noticed a small shake right at startup, but it would go away after about 15 seconds. I thought there was some condensation in the gas tank, so I filled up with premium, put in some Sea Foam, and made sure the gas cap was nice and tight. A couple days later, the CEL went on. Read the codes and it was a P0306.
I took it to a shop I trust on Saturday and they switched out the coil in cylinder 6, changed all spark plugs, and cleaned the fuel injectors. $350 later, I hoped the issue was gone, but the CEL came back on today. I still notice a slight shake on startup. Just pulled the codes for the CEL and it's a P0306 again.
So should I recommend my tech to look at the HG? I haven't noticed any usual signs of an HG going bad, but from what I've read, it appears that it could be. Any other suggestions before I take the 4Runner back in early next week?
Jerrydog
New member
I'm having a #6 miss fire as well. Do any of you find this even remotely acceptable on what is supposed to be a "reliable" vehicle? Head gaskets before 300+k miles? I can tell you I never had this kind of trouble with my 97 Pathfinder. and seriously 2200 for the repair? That's have the value of some of these trucks....
I've had the same issue with #6 miss fire. Mine occurred around 130k (3-4 years ago). Dealer quoted me $3500 for repairs and I said screw that. I never got it fix but my 4runner is still running strong at 190K. Knock on wood. I'm going to drive it till the engine blows then replace it.
So, its been doing the misfire/warning lights at start-up thing for 60k miles, without overheating or any other issues? do you lose coolant slowly, but just keep topping it off?
keep us posted on this. I've read of some people using Bar's Leak stop with some success also.
My truck developed this problem just as I decided to stop using it as my daily driver and was going to keep it for Home Depot / winter snowstorm duty only (so maybe 2000 miles/year max). If I can keep it going, even another 20k miles without a $3500 fix, I would be thrilled.
Jerrydog
New member
For the record I used the White label Blue Devil product. I read bad things about the yellow label. I only need my truck to last another year as well, I have been wanting to sell it as I'm not really a fan of it. I will post again if it fails or something else goes wrong with the POS.
misfire cylinder 6
same code on 05 4 runner 4.0
replaced all spark plugs,
same result
replaced the coil on 6,
same result,
replaced the fuel injector on 6,
same result,
I wish I had read this forum before I started throwing money at the shop! Why don't they read up on what they are doing?????>
I guess it will be the head gasket from here, but how long before I have to replace the head gasket on the other side???
:wtf::wtf::mmph:
same code on 05 4 runner 4.0
replaced all spark plugs,
same result
replaced the coil on 6,
same result,
replaced the fuel injector on 6,
same result,
I wish I had read this forum before I started throwing money at the shop! Why don't they read up on what they are doing?????>
I guess it will be the head gasket from here, but how long before I have to replace the head gasket on the other side???
:wtf::wtf::mmph:
CPA not a Mechanic
New member
First post - really amazing website by the way.
Googled "2004 Toyota forerunner running rough" and drilled down to this post.
I believe I have a blown HG. I have 230K miles, bought it with 7 miles on it September 2004.
Some months ago the CEL light and traction (VSC?) lights came on. Manual says it is most likely caused by PCV issues due to the gas cap not sealing tight. My gas cap may be faulty by the way. The light would come and go, and finally came on permanently.
Local Goodyear folks were able to clear the codes during oil change and I moved on.
At some point I got rough idle at start, after a warm up it would stop.
At some point I noticed overheating, discovered that the vehicle had lost coolant. I replenished and didn't really think to ask why I had lost coolant. Hence the screen name.
Anyway, I discovered that I required regular refills to the radiator to maintain engine temp in normal range. I further discovered I was leaking water - I could see it dripping from the engine onto the ground, near the inside of the passenger front tire. My neighbor says "looks like your water pump is leaking". Makes sense to me, right? I decide to keep filling the radiator at regular intervals as a temporary solution.
Just recently the car would stutter when accelerating while in gear. It didn't replicate while in Park or Neutral. This didn't replicate during very slow acceleration, as long as RPM's we less than 2K.
Just two days ago it was running very rough at start and almost had a constant stutter.
After reading this entire thread, with my very limited knowledge of combustion mechanics, I believe that I do not have a water pump leak, I believe that the water leak is from a blown HG and the water is forced out there. I partly say this as I purchased some white label Blue Devil (after reading this post) and followed the instructions this morning. After cool down, I started it up while I had some initial stuttering, it appears to have stopped temporarily.
It is too much of a coincidence that the issue abated after using the HG sealant correct?
I think there are other issues as well. I am embarrassed to say I don't know if I ever changed the spark plugs. :fish: Other basic maintenance issues sucha s oil change and air filter change, brakes I've done.
Any comments, advice, criticism? What should I do next? What other maintenance steps might I take, other than the obvious HG repair, that I see will start at $2.5K?
Great site guys, by the way. I wish I had this kind of mechanical initiative.
Googled "2004 Toyota forerunner running rough" and drilled down to this post.
I believe I have a blown HG. I have 230K miles, bought it with 7 miles on it September 2004.
Some months ago the CEL light and traction (VSC?) lights came on. Manual says it is most likely caused by PCV issues due to the gas cap not sealing tight. My gas cap may be faulty by the way. The light would come and go, and finally came on permanently.
Local Goodyear folks were able to clear the codes during oil change and I moved on.
At some point I got rough idle at start, after a warm up it would stop.
At some point I noticed overheating, discovered that the vehicle had lost coolant. I replenished and didn't really think to ask why I had lost coolant. Hence the screen name.
Anyway, I discovered that I required regular refills to the radiator to maintain engine temp in normal range. I further discovered I was leaking water - I could see it dripping from the engine onto the ground, near the inside of the passenger front tire. My neighbor says "looks like your water pump is leaking". Makes sense to me, right? I decide to keep filling the radiator at regular intervals as a temporary solution.
Just recently the car would stutter when accelerating while in gear. It didn't replicate while in Park or Neutral. This didn't replicate during very slow acceleration, as long as RPM's we less than 2K.
Just two days ago it was running very rough at start and almost had a constant stutter.
After reading this entire thread, with my very limited knowledge of combustion mechanics, I believe that I do not have a water pump leak, I believe that the water leak is from a blown HG and the water is forced out there. I partly say this as I purchased some white label Blue Devil (after reading this post) and followed the instructions this morning. After cool down, I started it up while I had some initial stuttering, it appears to have stopped temporarily.
It is too much of a coincidence that the issue abated after using the HG sealant correct?
I think there are other issues as well. I am embarrassed to say I don't know if I ever changed the spark plugs. :fish: Other basic maintenance issues sucha s oil change and air filter change, brakes I've done.
Any comments, advice, criticism? What should I do next? What other maintenance steps might I take, other than the obvious HG repair, that I see will start at $2.5K?
Great site guys, by the way. I wish I had this kind of mechanical initiative.
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Is the check engine light currently on? If so, take it to a local auto parts store and have them pull the code. They will usually pull the codes for free.
If it's a head gasket problem that' been occurring for as long as you say, then it's surely firing error codes that will point you in the right direction.
It does sound like the head gasket to me, however.
If it's a head gasket problem that' been occurring for as long as you say, then it's surely firing error codes that will point you in the right direction.
It does sound like the head gasket to me, however.
CPA not a Mechanic
New member
Yes the CEL is still on.
I'll take your advice and have the codes pulled.
What is the long-term prognosis if it is indeed a HG rupture?
I'll take your advice and have the codes pulled.
What is the long-term prognosis if it is indeed a HG rupture?
You'll need to get it fixed sooner rather than later. I just had mine done. It cost me $2500 and from what I gather, that's on the low side. My heads checked out find and weren't warped because it never overheated. if your heads are warped it may cost more.
The good news is that once it's fixed, it's fixed for quite a while. You shouldn't have to worry about it again.
The good news is that once it's fixed, it's fixed for quite a while. You shouldn't have to worry about it again.
I just did the head gasket replacement on my 05 4runner with 240k miles on it. I did the job in my garage .Took a total of around 20 hrs. Removed the engine from the 4runnner and did it on a stand. Took the heads to machine shop and had a valve job done on it $450. Parts and machining together were around $1200 with new pump and timing chain kit. Easy straight forward job with some exp of other engine removal and installs.
Vollostcom
New member
Did you ever get this resolved ?
i have a 2004 with slightly less miles, same thing going on just replaced the plugs definitely made the car feel better but still idles very rough upon start up. Had a compression test and is definitely not the HG... Did you ever find a solution to yours,,, let me know if you did , I am in Charlotte also do would like to know who you use for toyotas
i have a 2004 with slightly less miles, same thing going on just replaced the plugs definitely made the car feel better but still idles very rough upon start up. Had a compression test and is definitely not the HG... Did you ever find a solution to yours,,, let me know if you did , I am in Charlotte also do would like to know who you use for toyotas
I would still be willing to bet it is the HG, even with the compression test passing.
