I finally let my Acura dealer diagnose the CEL of my 06 TL 6MT, and just as I suspected, they told me an engine overspeed likely damaged the heads. They told me the max RPM is 8000 and my computer logged a max of 8300. I have accidentally downshifted into 1st instead upshifting into 3rd from 2nd before.

What I was wondering was if anyone had any suggestions for stiffer valve springs. I really don't want to pay thousands of dollars to have this repaired, only to mess it up again with another mis-shift.

I found this thread using the search, but the kit is over $500! I just want exhaust valve springs. Those are the only valves that get damaged right? Are there any stiffer exhaust valve springs available?

https://acurazine.com/forums/3g-tl-performance-parts-modifications-112/supertech-spring-retainer-kit-740202/

And is there any downside to running stiffer springs (longevity, fuel efficiency, anything)?

Anyone know the specs of the stock springs?

Thanks in advance.

 

I don't know the stock spring specs, and there isn't any info in the FSM, but replacing with stronger springs or even using shims under the springs has been done for years and normally used when the cam is replaced with a high lift unit to stabilize the valve train. The TL has a valve spring seat, so not certain if a shim could be utilized under the spring, but might want to look into this application. I would assume that the stock spring would allow the use of a shim without binding, but have never ventured into any modifications with the V-6. Only downside would be increased wear on the camshafts if the pressure becomes too great.

Probably been told this before, I think it would be just a band aid as what would stop you from shifting into a lower gear when the engine is at max rpm in next higher, and then nothing is going to help.

 

Not sure if you want to read this WHOLE 135 page thread....
http://googtl.acurazine.com/forums/s...d.php?t=718808

but it does have *i think* several members who have upgraded retaining springs and what not for their turbo build.

BUTT, exactly what turbo nut said:
its not going to stop you from doing it again.

 

Thanks for the replies.

I just got off the phone with the dealer and found out that only one of the heads needs to be repaired (only for cylinder 6). So if I get new springs, only one head will get them. I still want to go ahead and have the stiffer springs installed on the one head. Is there any reason I shouldn't do this?

I spoke with the tech, and he told me that one of the valves in piston 6 barely touched the carbon buildup on the piston. He didn't even see a mark on the piston from the valve hitting it. But that was enough to crack the valve guide.

 

Waste of good money to go through the procedure, especially if only one head is being done and as the peak HP is 6200 so heaven only knows what your doing at 8K+. Sorry to say, if you broke it once, it will happen again.
Good luck.

If you upgrade, get the stock springs and have one tested to see the results, or send one to me and I'll test it and send it back.

 

They told me it won't cost extra in labor to install the springs on the head that's already out for repair. The reason I was at 8300 RPM was because of a mis shift. The stiffer springs should prevent the valves on that head from floating in the future right? So even if I mis shift again in the future, that head should ok. If the other head gets damaged, I'll deal with it then.

I'll see if I can ask them to save the springs from the head they're working on. I wonder if one of the springs from cylinder 6 is bad.

 

That's a scary game you're playing only doing one head. You just don't do stiffer springs on only one head. The dealer also should have diagnosed the problem in more detail before pulling the heads. If one valve is bent, chances are most if not all made contact with the pistons. A leakdown test should have been performed first. What's going to happen is the car will run great for a while until the other valves burn from being slightly bent. You'll get another misfire issue and have to pull the heads again. Many times you can't see where the piston and valve made contact especially if the car has been run for a while after it occurred.

At 8,300rpm, you're lucky you didn't put a rod through the block. Think of valve float as a warning. Stock redline is 6,900rpm, not 8k.

 

According to C&D redline is 6800 and the limiter is at 7000.




Edit:

:oops:

Change that. It was Road & Track and it was a 6MT Type-S.

 

Is there a reason not to do stiffer springs in only one head?

Can I just wait to see if the other head acts up before I have it worked on? It's 10 more hours @ $136/hour to work on the other one. I've been running it like this for over 10k miles.

 

If you've run it that long, you might as well do just the one. Did you have a random misfire or a misfire on only one cylinder.

Replacing one side won't do any good if you overrev it again unless you're a very lucky guy. They can do all valvesprings without pulling heads. You pressurize the cylinder you're working on with an air compressor in the spark plug hole to keep the valve from falling into the cylinder. I'm not sure what they would charge you though.

FWIW, once the engine is in the state yours is in, it's less than an hour to pull the other head. Since it's still on, I would at least have them perform a leakdown (not compression) test. They're so deep into the engine, it would be a shame to not find all of the problems now.

 

The car reported a misfire code for each cylinder plus a random misfire, but the tech said that the car couldn't tell which cylinder was misfiring and that he was able to see that only cylinder 6 was misfiring once he hooked it up to his machine. When I first got the CEL, I only got misfire in cylinder 6.

Thanks for the suggestion on the leakdown test. I guess if the tech is willing to charge less on the second head, the cost of the leakdown test would be worth it.

Should I ask them to replace all the exhaust valves on the head that's out? It's the exhaust valves that the pistons hit right?

 

The tech told me that the machine shop said that all the exhaust valves were bent, so they replaced all of them. He asked me if I wanted the other head done. The labor cost would be half to do the other head (5 hours vs. 10). I decided to stay with the original plan (to just do the one head) because I figured that if doing one head stopped the CEL from turning on, I'd be good for now, but I just realized that one member burnt his valves because he waited too long to do a valve adjustment.

https://acurazine.com/forums/showpos...1&postcount=40

Other than saving 5 hours of labor, is there any reason I shouldn't wait until I get another CEL to have the other head done? If the valves are burnt, all they have to do is replace the valves right?

I also have another problem I'm trying to deal with. The service adviser originally told me the price he quoted (~$2100) was for both heads, but when I spoke with the tech, he told me it was for just one head. I agreed to the job thinking it was for both heads. Should I contact Acura Client Relations to see if they can help me? Here's the thread I started on the issue.

https://acurazine.com/forums/3g-tl-2004-2008-93/dealer-misquoted-service-price-what-should-i-do-i-already-agreed-job-857468/#post13780205

 

If all of the exhaust valves on one bank were bent, they're all bent on the other side as well. You'll probably have a random misfire right away if you don't do the other head. If you don't right away, it's just a matter of time for sure.

I would definitely go higher up if they're going back on their word. At $2,100 they're making a nice profit even doing both heads.

The high end of a head gasket replacement is $1,700.... that's the high end. It's the same labor plus valves, seats (or just lapping the valves in more likely) and assembly of the heads, I would say $2,100 for both heads is about right. I have a feeling they're trying to take your money.

 

They're not really going back on their word. My service adviser just misunderstood the technician, relaying the wrong information to me.

I readily accepted when I thought the ~$2100 was for both heads because I had called in the past and was quoted ~$4000 for both heads. I don't know what I would have decided if he told me the price was for just one head.

 

$2,100 is about right. $4k is a complete ripoff. You might as well buy a low mile used engine for that price. Maybe it sucks for them but they made the mistake, you based your decision off of what you were told. They should stick to what they quoted even if it was wrong. When I was in the business, that's what we did. If we misquoted someone, we had to give them that price.

 

I just thought I'd give an update on how my TL is doing after the head work on only the one head to get rid of the random misfire and other misfire codes.

It's over 11,555 miles later now, and the code has not come back once. During that time, I did mis-shift once but it did not produce any codes. Everything has been fine.

If anyone is interested in purchasing the springs, you can actually buy them individually direct from the manufacturer. All you need is one for each exhaust valve (plus the retainers). This will cost about half that of the entire kit.

 

lol mis-shifted again?!

 

^needs new driver mod.

 

I could see something like this happening to me.

 

concentrate, JJH!
always pay attention and it will never happen

 

Thank you JJH

 

I meant to say that it will cost about 1/4th the cost of the full kit.

 

Reminds me of this.







Exhaust valve exploded and holed out my piston into my crank case. Fun stuff!