StkmltS

Time flies when you're having fun... approaching 8 years on the rebuilt motor. I rarely drive the LGT, almost exclusively only on bad weather days when I know we'll see heavy rain or snow, or when I need to take more than 1 of my kids somewhere. The misfire still exists at 0mph but I've learned to live with it and it doesn't irritate me too much anymore.

A couple pics of my DD for fun. This summer I hope to tear off the rear end and give it the same treatment as the front. The kids wanted to paint a lightning bolt on the hood... why not?

It almost looks like pieces of an airline hose.

30k miles on the rebuilt motor (140k on the car) and nothing new to report.

Removed a drywall screw from a rear tire, plugged the hole, and found several bubbles on the inside sidewall 

On 12/9/2022 at 3:44 AM, ehsnils said:

I want one, now please.

My rear brake lines decided to evacuate all fluid onto the highway only a few days after the LGT became my primary vehicle. I managed to finish my drive home completely terrified but otherwise unscathed. The lines that failed were under the gas tank in front of the rear passenger wheel. Fortunately the brake line corrosion recall applied to my car because it was previously registered in one of the covered states (Michigan), so I dropped it off at my local Subaru dealership (https://www.josephsubaru.com/) and they let me drive home a '20 Legacy. They expected to have my car done the next day... 4 months later and the LGT is fixed. Apparently they can't overnight parts from Japan like that speedshop does in the original FF.

This is not the place to discuss my Miata but I can't resist giving you guys a peek. Attached pics show what the car has become. I've put several hundred miles on it and it feels great. Everything works except my high beams and cruise control. To address the minor, some might even dare to say "significant" changes, I'm making body panels for the front and adding aero goodies to the rear.

While your at the fill tube, make sure you inspect the evap lines and replace them if rusted while your there.

Most certainly.

Yeah it's still a party at 0 mph. Pretty soon I'm going to work on the leaky fuel issue (filler tube?) so maybe fixing that will solve the misfire. It's certainly not outside the realm of possible causes but I'm not too optimistic.

I wrecked my '05 NB Miata last week and the LGT has re-entered daily use.

I gave her a good wash and wax yesterday and she's as happy as ever.

 

I'll probably be spending time on the forums more regularly again as I drive the car daily.

You have been busy! 6 kids and this thread is 62 pages.

Did you ever replace your coils? just curious.

 

Yep, I replaced the coils before the rebuild.

 

Busy is an understatement. Keeping the LGT drivable is almost the most that I can manage.

That's good though, because if I had more disposable time I'd probably end up doing bad things to my ND Miata... which would undoubtedly make it a much less reliable daily driver.

The LGT is still running great other than the irritating misfire at 0 mph.

 

I can't remember how many kids I had the last time I posted, but we're up to 6 now... time to add a rear-facing 3rd row to the wagon?

Probably on his way to Autozone to buy a chrome M3 badge, new 8" wheel studs, and a ton of spacers.

I sit corrected, I bought the used piston from someone, from a different motor, and it was visibly much newer than my pistons. The skirt coating was almost as good as new.

 

I honed the block using a ball hone.

I did check for roundness... see the attached blank inspection sheet.

I don't remember the numbers but I do remember that the cylinders are not out of round.

 

Even with my minor oil leak (main seal or oil pan?) I don't consume any noticeable amount of oil between 3k mile changes.

Inspection - Cylinders.pdf

40-60 is a lot. Can't be fake IMO. The count peaks at 99 and goes back to 0 and increments again. From my experience, CEL gets triggered when it reaches 30+ a couple of times in a row or something.

 

 

So I am guessing piston #2 is new with new rings right?

 

 

 

Did you hone your block? I can't find the post in your thread. I mean, 65 pages man

Could be that even with new piston/rings, the cylinder walls in #2 are no good anymore, thereby not providing a good seal.

Another thing: when you put the new valves in, did you do a 'water test' or with brake cleaner before putting the head back on the block?

 

Another question: have you inspected your #2 spark plug recently and compared it to #4?

 

Yes I honed the block, and all pistons got new rings.

I don't remember which cylinder got the reused piston. That puppy was extremely clean before it went back in though.

 

I tested the heads with the new valves but I can't remember how long I let the water sit... maybe overnight, maybe just a few hours. Either way the valves didn't leak.

 

I don't remember when I last pulled the plugs to look at them. It's still misfiring so I have no reason to think #2 wouldn't look different.

 

I should take a video of the engine running so you guys can see what it looks/sounds like. It's hard to doubt once you see it.

ok. What's the peak roughness count again you see at 0mph?

 

 

 

I can't remember all the details.

But you've put new pistons in?

 

What did you exactly do to the driver side head?

 

Ever changed the crank position sensor?

 

Roughness... maybe in the 40s? 50s? Does the ECU go as high as 60?

I can't remember exactly how high it goes. I'm sure I have a chart in this thread somewhere.

 

I haven't changed any sensors.

 

3 new pistons + 1 reused original (see rebuild for embarrassing reason), new rings, new bearings.

Original rods and crank.

 

Both heads:

Cleaned

Polished (not ported)

Decked

New valves (with correct sized buckets)

Lapped valve seats

New valve seals

Reused original valve springs

TGV's are gone

 

Everything I've done to the engine was after the issue started, so I can be confident that what I've done didn't cause the problem. Maybe I've made it worse, but I didn't start it.

 

maybe the day you eventually replace your floor mats, the misfire will go away.

I could use a new front mat...

Are you still experiencing misfires in #2 now?

 

Yes, still only at 0mph.

Clutch in, clutch out, in gear, out of gear, any RPM, any coolant temp... doesn't matter.

Any speed over 0 makes it stop, regardless of the variables above.

 

Yeah, figure that one out.

 

Emotionally I've given up on searching for the root cause. It is what it is.

As the car gets older eventually the misfire will disappear as new parts replace old parts. Or it'll hang around forever.

Ok, excuse accepted.

Yes, I replaced all of the injector o-rings. Lubed 'em up and everything.

Nice. I need to do this too.

How have you not done this already? It's a no-brainer.

It works with generic oil/fuel pressure sensors too.

That thing looks fun

Yesterday I replaced my manifold-UP gasket with a double-thick grimmspeed gasket. It fixed the exhaust leak but I'm still only holding boost up to about 5psi. Around 5psi the turbo gets all herky-jerky and becomes the opposite of smooth until it tops out around 7.5psi. The tune maxes out somewhere in the teens so something isn't right. I think my next move is to shove a borescope down the DP to look at the cat.

I'm curious why it matters to have the matching VIN sticker. My OCD understands why, but practically does it matter somehow?

If you changed out the sticker on the donor door with one that matches the rest of the car, isn't that cheating/deceitf/fraud?

 

Maybe in 50 years our cars will be worth enough $$$ for people to desire a "VIN matching" collector car, but not now.

Oh, sorry about that. Here, have a pic of the curve (just ignore that curved rope):

http://3c1703fe8d.site.internapcdn.net/newman/gfx/news/hires/2017/studentsfilm.jpg

 

Its round cause the flat earth is a disk, duh.

Pollution is bad, yet we all spend money buying things made by processes that generate pollution.

A realistic solution is possibly impossible.

 

Allow me to pollute our minds with awesome stuff we (most of us) will never have.

What turbo are you running? My avo380 pulls hard all the way to (past!) redline. In 2-3-4 I find myself between 6200-6500 more often than I would like!

 

JMP's modified VF-40, upgraded a couple years ago during my rebuild.

It normally feels great, but my exhaust leak keeps me below 5psi.

Who knew that ebay headers would be a pain to get working right... I thought "not me, I'll make 'em work". Haha jokes on me suckers.