StkmltS

USPS says my new (used) fuel pump and housing are waiting for me at home. I'll swap it in later tonight if I have time after the kids are in bed.

 

*Update* Didn't happen last night. I didn't buy what I thought I bought so I'm back to fixing my housing and putting in a new (used) pump.

Sounds directly connected to fuel... and more injector related. You're getting excess fuel in Nr 2. Are these new injectors? How does injector timing look in your tables? AFRs? Seems on the surface that you are too rich in that cylinder.

The problem started when all four injectors were still OEM that came with the car. After I bought one used injector on ebay the problem continued.

 

I was still on the 100% stock tune when the problem started, so I doubt the problem is in the tune. Which injector tables are you referring to?

 

My AFR (per LVs) are almost always well within the ±5% that people say is acceptable. As of a couple days ago they were -2.60/0.60/4.60/-0.80.

 

In the past, increasing the fuel (lower target AFR) actually reduced the quantity and frequency of misses. So far that's the only thing I've been able to do that's affected the misfiring. I posted a few charts many pages back... somewhere.

 

Why do you say I'm getting excess fuel in #2?

I'm inclined to think that I'm getting not enough fuel (low fuel pressure, leaky housing, AFR slightly too lean, observed MPG consistently 1-2 mpg better than the displayed MPG).

Bummer

^ nothing wrong with that, although I haven't seen the file.

Maybe even add a few alignment tabs here-and-there to make assembly easier.

I love me some Kentucky rice!

My miss is not being caused by the plugs, coil packs, or injectors.

There may be a problem with the connectors or the wiring, but the devices themselves are not the root cause.

 

Until recently I was careful to only make one change at a time, so that if the miss changed I'd know exactly why.

My spirit has been broken, and now I'm totally satisfied just by blindly trying handfuls of fixes at the same time and praying for a change... any change.

 

Here's an short(ened) list of things that haven't caused a measurable change:

Original intake manifold o-ring gaskets

New intake manifold o-ring gaskets

Old spark plugs

Old spark plugs re-gapped

Old spark plugs w/ swapped positions

New spark plugs

New spark plugs w/swapped positions

Original coil packs

Original coil packs w/ swapped positions

New coil packs

Original injectors

Original injectors w/ new o-rings

Original injectors ultrasonic cleaned

Original injectors w/ swapped positions

New (used) injector in cyl 2

New silicone vacuum hose

Original TGV gaskets

New TGV gaskets

Rebuilt motor

FPR ref line relocated to the BPV

Cyl 2 is where I see the most misses (highest roughness count), but cyl 3 also regularly misses.

 

The dark brown spot on plug 2 is a stain from something. Maybe I got a drop of oil on it when I installed it during the rebuild. There's no missing material.

 

Up close and in-person, plugs 1, 3, and 4 look almost identical to each other. The only obvious difference between any of the plugs is the color of the ceramic on plug 2. It was very slightly off-white (and has a big dark brown spot), while the ceramic on the rest of the plugs was a nice crisp-white.

No apparent change to the frequecy of misses at idle.

 

Sent from inner space.

Cylinder 2 has a little bit of fluid pooled at the bottom.

Cylinders 1, 3, & 4 are dry, and look as dirty as expected after 8k+ miles.

 

I fished a paper towel around inside cyl #2, and the liquid has the distinct smell of fuel, but the color of oil. Plug #2 came out wet (not enough to drip) and smelled like fuel. So I'm saying the fluid in #2 is gasoline.

 

 

 

1 - 2 - 3 - 4

(left to right)

 

New positions: 1 (was 1)- 2 (was 4) - 3 (was 3) - 4 (was 2)

 

I also put in four new non-OEM coil packs.

 

 

 

Does pressure inside the tank (or the lack of) somehow effect fuel pressure at the injectors?

After my drive home today fuel pressure @ idle was a steady 26/27 psi. I dunno if it's causing my problem or not, but it seems out of spec enough to justify spending a little money on a new/used pump.

 

Sent from inner space.

What does losing a gear feel like?

 

Since the mood in here has already been set to "negative"... My friend's turbo blew a few days ago and now he's facing the evil YNANSB monster. Is there anything special I need to know about rebuilding a post-facelift 4th gen?

How are you logging? (BtSsm, Cobb AP, or laptop)

 

Pop the ol' hood and follow the wires coming out of the sensor. If you can tell us where they go we can probably help you figure out where to look for the problem.

pretty

The rebuild has a little over 8k miles on it and all is well.

Tuning is fun, boost is fun, and 18 mpg is not fun. The car has been surprisingly uneventful lately. Even the oil leak seems to have stopped.

 

Oil consumption is a thing, but after 2k miles on this oil change the level just now dropped below the full hole on the dipstick. I check the oil every time I get gas... I'm pretty sure that's going to be a lifelong habit.

 

I keep BtSsm open 99% of the time, and I never (ever?) see knock events in situations that would be concerning. I do occasionally see knock between shifts, but I think that could be related to the exhaust hanger near the transmission that my exhaust isn't hanging from anymore. I bent the hanger for a reason I can't remember now, and I never bent it back. I know I should fix it, but I've really been enjoying my time spent anywhere other than under the car.

 

It looks like I may have found my gas leak. I drove around for a few days earlier this week with my rear bench out and the tank access cover off. WARNING: Only drive with that cover off for a few days if you really want to get paranoid about your car. Man alive, you can hear every bump, squeak, and groan the car makes. And you freak out whenever you're next to a semi on the highway because of all the scary noises you think are coming from your car because you don't fully trust the guy who rebuilt the motor. Anyways... fuel is definitely leaking out from the top of the tank. The gasket is relatively new so maybe there's something else going on. It looks like fuel is either leaking out past (in spite of) the gasket, or it's coming out of the top around the the little plastic do-hickey that the fuel line connects to (the bottom fuel line in the pic). In my misfire thread I've been exploring the relationship between my lower-than-spec fuel pressure and my misfires, so dealing with my fuel leak could have something to do with the misfires. I like throwing two stones at one bird, so solving the fuel leak is at the top of my list of things to do when my wife isn't home.

Thanks Dave, talk to you on Tuesday. Anyone here has a PLX wideband sensor? I'm trying to log my wideband for the first time but I'm not getting anything after selecting it from the plugin or external sensors. If someone can point me in the right direction I'd really appreciate it. Thanks.

 

Sent from my Nexus 6P using Tapatalk

I have the PLX and I've never had any issues with it.

How is yours wired? Mine is sending the signal through a deleted TGV sensor.

Since I started playing around with tuning I've gained so much more respect for the phrase "like a finely tuned machine".

 

Tuning is awesome. Making useful changes to a car (for free) AND learning.

I didn't realize the target AFR table (Primary Open Loop Fueling) was that less-than helpful. That would explain why I haven't quite gotten the results I was shooting for by playing around with that table.

 

So when I want to make a small group of cells slightly richer in order to address FKC events, or to make the CL/OL transition smoother like you said, I should increase the appropriate columns in the MAF scaling table... and then do what with the primary open loop fueling table? Do I also change those few cells to the end result I'm hoping for so that my fuel trims stay under control? If I'm understanding correctly that would make sense (not being sarcastic).

 

At the bottom of the table in RomRaider it even says "Estimated Air/Fuel Ratio"... geesh, I wish I would have noticed that before now.

 

When you mentioned the disconnect between desired and actual (12 to get 14.7) were you talking about the value in the primary open loop fueling table?

Why are you adjusting the MAF scaling instead of target AFR?

I'm still a tuning noob so maybe I didn't understand you correctly.

After my motor warms up my fuel pressure at idle typically hovers around 30psi. So that's roughly about 5psi less than what it should be.

 

Is 5psi enough to cause my problems?

Mmmmm... sexy teardown pics!

Aw you'll be fine. It'll be just like when I take my scout group hiking. The slowest goes in front to set the pace. You'll have fun because I'll be trying to stay on your tail, and I'll have fun because he'll be trying to stay on my tail. Even the slowest car can break ahead of the group at times, so having more HP in the rear gives everyone the ability to catch up with the car they're behind. It also helps keep the group's speed mostly under control. I'm all for driving dangerously fast, but driving fast as a group in an uncontrolled environment is asking for trouble. I like to think of it as driving irresponsibly, in a responsible way

I am seriously considering modeling up a honeycomb mesh that once a stock grill is cutout is a drop in piece... Don't know if it'll be worth it but I want to try it to say I did haha

 

Do it! I'd have to print it in at least 3 parts, probably more like 6 (2 high x 4 wide), but I'll totally try it out.

Nice see another Cincinnati Legacy Enthusiast! Killer B Pickup and windage is such a nice piece. Looks like a fun build

So, when are we all going to go for a drive?