Hi, i have a weird problem with my Tl-s, when i start the car, the engine missfired for few second at time and also i feel the car shacking on idle. I did check a scanner the fault was missfire on cyl. #5. I did replace the spark plug and i switch the coil on cyl. # 5 with the #6. The day after, check engine light came back on for missfire on cyl.#5 and cyl#3!with a different coil on cyl.#5... :s. The guy did do the diagnose with me think i have more then one bad ign. coil but i did put a brand new coil on cyl.#5 and still have missfire on cyl#5! Please tell me somebody see that before!!

 

Nobody have an idea??!!

 

I guess the first question is how bad or how often does it misfire? The TL will intentionally misfire in the first 10 seconds or so to speed catalytic converter light off. On mine its maybe one misfire every second or two, you have to pay attention to notice, a passenger would never notice.

Generally speaking a misfire when cold (assuming its not intentional) is usually mechanical in nature and one that appears only when hot are usually electrical in nature. Low compression will usually show itself as a misfire at idle but go away as speed and load increases. Of course there are always exceptions.

Its doubtful you have multiple coils going bad at the same time. While it can still be electrical I would to a compression check.

 

It was not doing that before, right now it's happen every time the car is sit for more than 1 hour. 3 times it turn the check engine light on and it just doing that around 5 second. I was thinking of coolant goes on that cylinder when it's cold and cause the missfire till the coolant it's burn. I did perform a leak down test on the cooling system, the test shows ok so it's not that. The think i don't understand is why the engine doesn't missfire at all when i drive... I will probably drive the car like that till it goes worse, than i will probably see if it is better with new coil.
Thanks for your help.

 

Did you do something like powerwash your engine where water could have gotten into the plugs and rusted them and the coil leads? If not, then there is next to no chance that multiple plugs and coils are going out at the same time. This is the common bullshit answer to this question that most "techs" will give anymore, but the odds are against it.

It is possible that coolant or oil is leaking into your cylinder, but you would notice low levels of either over some period of time if sufficient quantities were present to prevent a spark. Usually the the mixture will still fire with a fair amount of coolant or oil present. Are the levels low?

The advice is good - check the compression. Report back with compression on 4, 5 and 6.

 

The oil and coolant level are ok. I will do a compression test, do you think if the compression is not good on one cyl. that can cause missfire when i start the car??

 

Yes.

 

I don't want to scare your anything, but if the compression is low, then save your money. I hope that it is something else. I look forward to the results.

 

in for results.
let me share some of my war stories, i dont know in your states but here where i am our customers feel like their tls will float. meaning they will run their cars thru high hell water thinking itll make it. IT DOESNT.
long story short, water sucked in engine, engine dies, water slightly bends rod, after water is expelled burned off or what ever the matter may be the engine runs fine little to no power loss noticed, xxxxx miles later this happens.
another story i have is a fellow tsx owner with a cold air intake says as driving on hwy, car died etc etc.well theres a friggin rod sticking out the block. after removal of head, the carbon deposits alongside cylinder walls LOOK the same, but after carefully measureing, one noticed the one with the thrown rod(literally) has a slightly longer deposit ring. what does this tell me, the cold air intake more than likely sucked water in at one time, bent the rod and afterxxxxx miles later the stressed rod gave way.
so iguess my question is has your car ever been in a flood?

 

That's a very good explanation. I fully agree.

 

I did purchase the car 2 months ago the car is a rebuilt but it was repair 2 years ago and the previous owner didn't have any problem with the car before ... I don't have a cai, just a aem air filter put on the stock pipe. I just started to notice the engine missfire 2 weeks ago! The engine missfire everytime i start the car now but still just for few second and the engine light is not on. Bend rod i think the engine will missfire when i drive too??

 

Acadien,

Browse through my thread '07 TL Bad Engine Issue Today.. HELP!' I had all the same issues as you and had zero compression in cyl #4. Reading my thread could also help you get it fixed without much hassle like I just recently experienced.

Hope it helps.

 

Wow what a nightmare for you!! I did speak with a technicien about the problem i have with my car and he think it's probably a valve problem or timing belt!! But my car just shaking when the car is on idle, it's fine when i drive :S Also i'm not sure if i tell you that but i did replace the coolant thermostat last month, the seal was broken so the thermostat stays open. Since that i smell the coolant at time but the coolant level is fine! I will book an appointment with this technicien in the next couple weeks.

 

That is 100% not a timing belt. Absolutely impossible, what's wrong with these so called "techs"?

 

Ok so next step will be to check the compression on each cylinder to see if it's ok. If it's not ok on cyl.#5 what is my next step? Thank you for your help, very appreciated!

 

Next step if compression is low is to #1). never got see that "tech" again, 2). take the valve cover off and see if there is something inhibiting proper valve function on the upper end.

Did you ever have somebody do a valve job on the car? ...or did somebody own the car before you? It is possible that the valves are a bit too tight on that cylinder.

Are you still under a warranty, by chance?

 

Yep. And after that, squirt some oil in that cylinder and see if compression comes back up. After that, pull the heads and look for a blown headgasket or obvious signs of mechanical failure.

 

oh yeah that part about replaceing the thermostat is very important. so you replcaed it because it was stuck open? if so how did you determine the thermostat was stuck open to begin with? wha were the signs displayed by the vehicle/

 

The engine won't get to full temperature.

 

The temperature won't get to full and gauge returned to 0. temperature was -25 outside. I did put an injector cleaner in my gas tank this morning just to make sure it's not something with an injector, never know...

 

*Update, I did have an appointment thursday with another tech to diagnose the car, Bad part is i found this week end the coolant level was very low, I did check 2 weeks ago and it was good, so I think the problem is there... maybe coolant leaking on the cyl. #5 .

 

Possible. I hope not for your sake, but it makes sense. If so, then it will likely need a new head gasket.

Do you have any white smoke coming out one of the exhaust pipes that is not coming out of the other? What about at start up?

 

Please do yourself a favor and run some more diagnostics yourself before the dealer gets involved and really screws the procedure up. Pull the plugs and look for one thats cleaner than the rest. Do the compression check. Have a smog shop sniff the radiator with the cap off to see if it has hydrocarbons in it. Make sure there is no water in. The oil. Once the dealer has the car you're at their mercy. If you have more data before you bring it in, you're better protected.

A headgasket issue will only get worse and let's remember water is not a good lubricant for the cylinders and rings. You can also fire cut a groove in the aluminum heads and block if it goes on for too long.

When you checked the coolant level was it hot both times or cold both times? Just making sure you're not seeing the normal cold to hot variation.

 

I totally agree with you and I would even shoot the temps of individual headers to find the problem cylinder. The only problem is the Tl merges both banks and then splits it back into two pipes so its not a true dual exhaust.

 

OP, what year is your TL-S?

What was rebuilt on the car?

 

check the wires to your plugs and distributor one may be crossed or came off.

 

Hi, now I know it's a coolant leak the cause for missfire, We will put some pressure on each cylinder to see if it's a headgasket but for me i think it's not that because I have a missfire on cyl#5 (Front head) and cyl.#3(rear head) what's the bad luck to have to bad head gasket... Do you know if we have a way to check if it's the intake gasket?? Intake gasket can cause leak on both head right?

 

I guess I don't really understand that paragraph...How do you know a coolant leak is causing the misfires if you haven't done a compression check? Did you find coolant in the oil or vice versa? Do you have white smoke coming out the exhaust?

Yes, it's possible to have two blown head gaskets. You still haven't told us what was rebuilt on the car. If it was the engine, it could be that they did a crappy job.

 

I can't remember the TL specifically but most cars have odd numbers on one bank and even on the other. Blowing between two cylinders is common.

 

#3 and #5 are on separate heads:

firewall
123
456
radiator

 

White smoke when they start the car and we can smell the coolant in the exhaust... I did call the Acura dealer just to ask if they see 2 bad head gasket in the same time and they said no and also they never replace a head gasket on the 3rd gen. Tl :S For the rebuilt title the previous owner said it was body damage and few parts on the front end.

 

Yes that right, that's why i think more Intake gasket then 2 head gasket...

 

If it had front end damage it could very easily have been overheated and warped both heads. If there is a tuning problem like a lean condition caused by a fuel pump that's not bad enough to show any obvious signs but will lean out the top end.

If the cylinders aren't side by side, I agree to go for the intake gasket first but don't be surprised if you have two blown head gaskets. Why not just pull the plugs and do a leakdown to confirm whether it's a headgasket or not. This is assuming the TL has water through the IM near those cylinders.

 

How is a bad IM gasket going to cause a coolant leak into the cylinders?

 

I'm probably not the best to explain that but from what i understand, coolant goes to the cylinder when the valve open...

 

Only if you have an IM gasket leak and only if there's a water passage right next to that cylinder. Sometimes the heads have "dummy" dead end passages that the intake manifold and gasket seal off that can get into the cylinders especially since the water is pressurized and the IM is under a vacuum. Still not very likely though.

You could start by checking the torque on the IM bolts around those ports.

However, having two leaking IM gaskets are more rare than two blown head gaskets.

 

After searching through images for the last 20 minutes, I can't see water anywhere near the IM. No blocked off water ports in the heads, none flowing through the IM itself, nothing visible. You could always have a cracked head allowing water in but who knows. A leakdown will tell you where to go next.

 

You have to take the intake off to get the heads off... so dig in. If the intake gasket show signs of leakage, then check the intake and heads for flat, replace the gasket and try it out.

If the intake and upper heads are not warped, then keep on going.

 

OP, it's not your IM gasket....I've had the IM off and there's nothing there....I suppose a massively leaking head gasket could theoretically allow coolant to flow across to the IM gasket, but I'm not buying that...you'd have steam under the hood and would be able to smell the coolant...
i

 

Ok, I'm sceduled to do the leakdown test on each cyl. tomorrow morning, I will let you know the result. For the cracked head it will missfire all the time or didn't come worst and worst i think :S... Thank you for your help with that i'm able to try few more things.