Warning, this is a bit of a wall of text, but I have a couple questions in here, I'll bold those for reader convenience, and some info on some weirder problems that may help someone who's wanting to rip out their hair at some point.

So it's been an interesting year and a half or so for my 08 TL. As I had a few parts need replacing (O2 sensor, evap purge valve, air intake hose, etc.) and some big services (timing belt package, spark plugs, etc.) I've been really putting my time and energy into treating my TL well to see it to some excellent 200k mile+ golden years. It's generally had none of the common TL problems (cracked dashes, transmission issues [which it shouldnt as an 08, but my gratefulness is still there], early engine mount death.), and other than some of the small parts and regular service needs as mentioned, had only had it's alternator needing replacement until recently. This last year we started getting missfires. They were getting severe. We pulled the plugs, which had been replaced maybe 10k miles or less before and all of the nodes were burned down entirely. I replaced them...missfires returned a few weeks later, but the nodes were okay. I replaced them again...a few days later it returns. We replaced a couple ignition coils, but the problem continues. My mechanic was stymied...but I have lost a lot of confidence in them this week. The missfires themselves are never at idle (pull any coil plug off and all of them cause aggressive missfiring at idle). Move plugs and coils around and no changes, but it's not always the same cylinder with the issue. Anytime I open the throttle, that's when it hits, and someone I know suggested checking out the fuel pump as it sounds like insufficiency. I'm bloody well hoping this is the case as otherwise the mystery continues.

As such, on the fuel pump side, can anyone help me with ways to check if this is an issue? I know how to access it, but to check to see if the pressure it's putting out is enough, I'm not certain how to proceed. I could just replace it, but putting the money out before I know if it's the problem and being less certain about the specific origin of the problem makes me want to not skip this step.

Also, because of some of the expenses described below, I'm really wanting to track down this missfire issue because I don't want to sink money into a lot of the below, if I have this continued mysterious missfire issue that may slowly be damaging the car due to the fuel mixture and any compression abnormalities, and making it hard to keep driving or sell. Any other ideas to check for to track down this missfire would be MASSIVELY appreciated.

So, some other interesting things. I'd run into my car dying, not being able to jump it (despite cleaning off the nodes aggressively), and having AAA replace the battery as faulty and confirm it's not the alternator. Two weeks later, the battery is dead again. It's not the battery, nor the alternator, but a parasitic drain which is getting dramatically more aggressive. I bring it in, they find the AC compressor relay is stuck, keeping the compressor on all the time. They fix it, I drive off on a friday, stop for lunch in the city...and my car dies the moment I turn it off. Just before that, the AC went on full power, and woudn't respond or turn off. They take it back, and tell me the blower motor and it's relay are bad, and want 400+ damn dollars for it...thanks to websites like this...and the glory of youtube, it's under $100 of parts and like a 20 minute process with basically just a screw driver. They found that this issue was causing a fuse to blow and stop my car from being able to turn on or even access the battery (the AAA was stymied that he couldn't even get sparks from the negative plug). I'm hoping to actually just disconnect the relay on the street, turn on my car and drive home to work on it myself.

The one other thing really going on is the front and side engine mounts need to be replaced, but it looks like some basic wrench tools and a ground jack should take care of this for about 2-300$ instead of 600+! But again, I'm resisting replacing these parts before knowing the missfire issue can be tracked down and fixed. Any specific suggestions for places to buy these inexpensive, but keep OEM? I see a lot of painfully cheap ones and so expect I want to stick with OEM for these, but don't know if I'll find better options than buying direct from Acura/Honda (which always hurts my soul).

I appreciate any input and thoughts! I'm hoping to get back to another 50,000 loving miles with this car at least before it makes the trip to automotive Valhalla.

< /wall of text >

 

wow.....surprising how many problems on an 08. I use RockAuto for most of my parts, or one of the discount online Acura sites.....just Google Acura parts and compare prices. I know that I got some from Acura of Tempe, and some use Bernardi, but there are a bunch that will quote much cheaper than local Acura dealer. An 08 treated well should last well into 200,000 and beyond. My 07 has 290,400 miles and is running great. Minor oil leak for the past 150,000 miles but otherwise doing well. Good luck.

 

Are you using OEM plugs? OEM coils? ARe you saying that the electrode of the spark plug burns off somehow? that's a problem, definitely.. gotta figure out the root cause of that.

When you replaced the alternator, was it OEM or DENSO?

Did you remove the HFL or confirm if that's not causing another parasitic draw?

 

NGK plugs, denso coil replacements. And yes, the center electrode of all 6 had burnt off in about 10,000 miles. Subsequent replacements haven't gone long enough without misfires to get to that point. The alternator was a few years back, done by a good quality shop in the area, but I don't know what they used. I haven't had any issues with it, the batteries have been taking charge plenty fine. HLF?

Thanks Quantum, I'll check out that store and see what I can find.

 

Your misfires are probably cause by the valves being out of adjustment so adjust the valves to spec. Good luck.

 

Did it matter since the OEM and Denso alternators are one and the same? The Denso IS the OEM without the Honda name on the package.
.
.

 

did you buy the plugs from ebay? I've seen quite a few fake NGK spark plugs from ebay

 

The plugs have all been Ebay, though 3 different sellers, 3 different sets, and I believe I bought at least one set directly from NGK's ebay store.

I'll take a look at the valve adjustment. Anyone have a link to a video or text tutorial? Having problems finding any specific to the engine in an 08 TL on this forum or Youtube.

 

Cheap out on the side motor mount, those are easy to replace yourself and takes only about 10-15 minutes. I'd get OEM for the front and sides though. Pricey but well worth it considering the labor involved

 

Check your plugs, I gotten fakes from ebay and almost ruined a motor:
The ones with the burnt tips are the fakes (bottom) with less than 5K miles vs the top factory OEM one with 105K miles: Real plugs have slanted /////Japan//// vs the fake that are llllJapanllll plus the ceramic is allowing for a lot of blow by on the new plugs.

 

I'm just going OEM for both engine mounts, they're not crazy expensive overall, and it's an important part that acura has had issues with before, so I'd rather not scrimp. Labor isn't that bad to do it myself and saves me $400 on someone else doing it, so it's a good savings even with OEM.

Much appreciated Csmeance, those look a lot like the first set I replaced. I'll have to see if I held onto them to check for that. I have one sitting here on my desk that has "/ ASSEMBLED IN U.S.A. FROM JAPANESE PARTS /" I'll have to look at the full set I have sitting in the trunk my my TL (which is at the mechanic, grabbing it next Monday. Just having them replace a fuse since they've already messed with it and I'm doing the rest). Where do you source yours from?

 

Are you getting any CEL codes?
Are you getting lean or rich codes?

You'll need to check the fuel pressure.55-63 PSI at idle.

The regulator, filter, and pump is all one assembly.

I'm not understanding your issue here.

 

Much appreciate the info on the fuel pump.

The CEL codes via the nav comp are just cylinder missfires. Once I get my TL back and do a couple basic things, I'll be seeing what codes I can pull. I know there were a few but it's been a while, and none were directly about fuel mixtures, they were something along the lines of some solenoids I believe.

 

Do yourself a favor and just get a set of Denso Iridium power IK20. I'm not understanding why people are dead set on NGK all the time when it's known to have a very large batch of counterfeit ones. I actually heard of a blown motor on a Civic using fake NGK iridium plugs.

 

Have a link to some Denso Iridium power IK20 that fit the 08 TL? Amazon couldn't find any, I'd like to make sure I'm snagging the right thing if I consider them.

 

I found the codes pulled earlier this year before I did some of the work listed above, but it seems unrelated. Once I get the acura back and do some of what I described here, I'll rerun the codes after a bit and see what we get.

P0767 Shift solenoid valve D stuck on


P0796 clutch pressure control solenoid valve C stuck off.

 

I don't believe you couldn't find any Denso Iridium IK20 on Amazon, I found them right away.

 

It wasn't that I couldn't find any, but that the only ones that came up, amazon said didn't fit my 08 base TL. The link you sent seems to have no car specific check like normally automatically comes up.

 

IK20 and IK20TT both work for your 2008 Base TL. You can't trust Amazon's selector sometimes. You go to the source, http://densott.com/ and plug in your car's year and engine that's it. TT is the twin tip, IK20 is the original Denso Iridium. I have used both and both work the same.

 

As much time as you have gone back and forth on which part is right and if they are legit, have you just considered going to your local parts store and buying there? Or even the Honda dealer? Or one of the Acura/Honda dealers that run an online store? There are plenty of ways to purchase parts outside of Amazon and eBay.