Vlad_Type_S

iTrader: (3)

So here's the story. I got a P0171 a couple of weeks ago and the dealer said that a valve adjustment is the first step in troubleshooting. If you're wondering why I took it to the dealer, it's because the car is still under warranty. Unfortunately, it does not cover maintenance procedures such as a valve adjustment. They wanted 600 bucks and some change. I said screw that I'll do it myself. The car is fairly new and young (66k miles) so it's friendly to work on (unlike my mom and bro's beaters).

I picked up the valve cover gaskets and spark plug tube seals yesterday and I blocked today off to do the valve adjustment on my 08 TLS.

Since I'm so smart, I did a bunch of driving this morning before actually getting to it and then realized that I can't adjust the valves until the heads are cold!

So the actual adjustment will happen tomorrow. But none the less, I removed everything down to the valve covers and made several noteworthy observations. One of these is that the spark plug tube seals were super stiff and very difficult to remove. I'm wondering if anyone else experienced this.

Otherwise, I'm just going to show some photos of the parts. I am particularly concerned about two things.
1) The rear head is not nearly as yellow as the front one. Could this be a sign of a problem? At first I thought that it may have been replaced before I got the car, but that can't be because the cams and rockers are just as worn as on the front head.
2) The intake manifold is dirty. Very dirty. There's crap all over the EGR passages and I'm quite concerned about this. Is this normal? If not, what do you guys think could be the issue?

All the pictures can be found here: http://s1307.beta.photobucket.com/us...t%202008%20TLS

Here is the intake manifold after the cover was removed.



Here is the cover:


Here is the inlet to the intake manifold:


Here is the IM side of the throttle body:


Here's the front head. Note the intake runners blackness:


The front cover:



The rear head:


Here is the rear cover:



Here are the rocker arms. Clearly worn: I'm probably not going to use Honda fluid anymore.




Is all of this normal? Looking for some advice from the AZine pros. I'm sort of car savvy but I've never tore a V6 apart to this point so I'm not sure if this is all normal. Any comments are greatly appreciated!

Thanks all,
Vlad

truonghthe

looking normal for me, how many thousand miles on the clock?

endles/acura

Everything is normal,i've seen all that before hundreds of times.

Vlad_Type_S

iTrader: (3)

Sweet. I'll sleep easier. Thanks for posting!


Just 66k. I scooped her up with 35k miles 20 months ago. And while most of my miles are from long highway trips, there is a lot of spirited driving in between. That's why I'm concerned.

Thanks for the feedback!

gwiffer

iTrader: (7)

Were the front bank exhaust valves too tight? For some reason it looks like it's running hotter than the rear bank b/c of the varnish.

Your code P0171 is a lean bank 1, so I'm confused.

04WDPSeDaN

iTrader: (1)

Welcome to honda/acura's piss poor intake manifold system. they always collect oil and get gummy. Using a few cans of intake cleaner you can clean out that entire manifold. I wouldn't spray it directly into the throttle body since it may likely cause the drive by wire unit to fail. I would spray it on a durable cloth and wipe it clean while holding the butterfly plate on the TB open.

Another thing, that is a NORMAL look for the heads if your using conventional oil, and possibly exceeding the life of the oil. Switching to synthetic oil, (Castrol edge or MB1 or redline) and using it for approx 5-6K would clean up that engine very well. Another thing about CARBON build up, mostly happens with using anything lower than 93 or top tier gasoline and extended periods of idle (traffic, letting the car warm up ect ect).

Another maintenance item skipped, happens to be the PCV valve. Look at your intake manifold, it's pretty terrible. The PCV valve is located on the lower left corner of the front valve cover, held in by 1x 10mm bolt. I would suggest replacing it and cleaning out that entire manifold w/TB.

You will notice after you do all this the vehicle runs better, smooth and responds-accelerates better. I usually do my intake manifold cleaning once every 15K. It doesn't get terrible, however it still collects oil. In most cases it's the rear head that gets darker than the front but let me assure you, I've been running synthetic for 75K now , just recently removed my covers to paint then and noticed the heads were pretty much like new condition.

nismopowerdqg

this is good info^ im switching to synthetic next oil change!

Vlad_Type_S

iTrader: (3)

First of all, thanks for all the advice! There is no way I would have known any of this. I sincerely appreciate it.

Is there a specific product you would recommend? Will some CRC do the job? [link]

I asked my dealer whether they used conventional or synthetic. Obviously, conventional. I don't exceed the life of the oil by mileage standards: I get it changed approximately every 5k. But I should have probably realized that my spirited driving on an almost daily basis due to being late to everything all the time would require more frequent changes of conventional oil. I am ashamed of overlooking this. Definitely going to switch to synthetic and monitor the heads' appearance. Should be an interesting experiment to see how the engine changes after using Honda oil for 65k miles.

I believe 91 is the minimum octane and I've never put anything less than that in there. I also only use BP and Shell fuel, no exceptions. I lived in Wisconsin for about 20k of the 30k that I've put on the car and had the opportunity to use fuel with no ethanol added for all 20k of those miles. Now I live in Chicago so I've been using the 10% ethanol premium that's available everywhere and stop-and-go traffic is a daily occurrence. I wonder what effects the ethanol has. Any opinions/thoughts on this?

Yeah, it's pretty terrible. That's exactly why I started this thread. I'll swap out the PCV valve. As far as cleaning the IM out, I expect that this means taking the entire manifold apart. I assume there is a gasket in between the two halves, but I can't seem to find a part number for it. Is it re-usable?



Thanks again!!!!!

04WDPSeDaN

iTrader: (1)

Np, that's what most of us are here for.

Vlad_Type_S

iTrader: (3)

I should have been more clear, forgive me.

I meant the gasket that is between the upper and lower half of the manifold itself, after it's removed from the runners. If I may direct your attention to this link: http://www.oemacuraparts.com/parts-c...ntake-manifold

The intake manifold is item 7 and it appears to be made of two separate parts, held together by the unidentified bolts. Do you split this apart when you clean the IM? Or do you just spray inside of there and get it as clean as you can without opening it up?

As an aside, I am fascinated to see how the butterfly valve creates an open plenum at full throttle and long, narrow runners at idle: I would love to see the inside of this thing.

sixsixfour

i hate cars recently had a thread doing a valve adjustment as well. you might find his information helpful.

04WDPSeDaN

iTrader: (1)

Sorry for the misunderstanding, I have never pulled the manifold apart, but it would be the best way of cleaning it!

nfnsquared

OP, first of all, your dealer is an idiot. It's highly unlikely that a valve adjustment will resolve a P0171.

2. The spark plug seals are a PITA to remove/replace. Mine were in excellent shape so I left them in place. It's really hard for me to believe that they need to be replaced after only 66K miles.

3. The SM says to replace the manifold gaskets, but I reused mine with no issues (only because I had it torn apart before I realized that I didn't purchase new ones, doh!)

4. I think your issue is with air intake, not oil. I've never seen a throttle body that dirty/tarnished. And at only 66K miles? There is clearly something wrong with your air intake/filter system for the throttle body to be that dirty. I'd start there.

Vlad_Type_S

iTrader: (3)

Haha, I don't particularly enjoy any of the service that I've received at this dealer. Every time they call for a survey, I'm sure to point out their dishonest recommendations and the guilt trip they try to give you to make you buy whatever they're selling. In this case, they refused to do any additional troubleshooting until the valves were adjusted. They cleared the code and it hasn't come back yet. I suspect that this was a freak occurrence.

The tube seals were stiff, but definitely had life in them yet. I replaced them only because I already got the new ones and had everything apart. I used a hammer/chisel to remove them surgically and used a rubber mallet to get them in. I didn't actually hit them, but rather laid the mallet on the seal and hit it with a 2nd hammer.

The air intake was my first thought too, but then I noticed that the inlet to the manifold was all oily as well. Since I'm not familiar with the passages of the intake manifold, I didn't discount the possibility that EGR gasses hang out where ever they want. Common sense tells me that they wouldn't hang out at the ass-end (technical term ) of the butterfly valve though so I am still confused as to how the heck it got so dirty. I've always ran the OEM filter, the air cleaner cover is not damaged, the bolts that hold it down are not damaged, the air flow tube between the TB and air cleaner is not damaged, and both clamps are secure. I can't think of any other reasons that the air getting in there would be so contaminated, but now I'm going to check my sanity and inspect all of these components in greater detail. Thanks for the advice!!

nfnsquared

Sorry, totally missed that that was the backside of the TB. In that case, I'd guess the EGR system is malfunctioning. Could be that the EGR valve is stuck full open 100% of the time, dunno.