cylinders 2 and 4 running rich :confused:
 

So I'd been wondering why in the hell my car was cruising/idling/everything pig rich (like 11.5 and richer CONSTANTLY) and thought I'd change my plugs. This is what came out, cyl 1 on left, 4 on right:

Attachment 212784
Attachment 212785

So, judging by those, I don't think it's my tune...

Here's two logs, just driving normally to and from work:

are you even getting fuel in 1 and 3?

I would think so? There's a bit of soot on them, just not as much as 2 and 4.

I don't know dude, I'd clean/replace the plugs and look again in a few days.

Swap injectors around.

I'd try swapping your injectors around and see if the problem moves with them. You might have two leaky ones.

*edit* sam beat me to it.

maybe, but not unless/until the symptoms repeat.
identify a problem before looking for a solution.

I should mention the car idles like a Subaru and bucks a lot during cruise, definitely NOT smooth anymore. I remember the cylinders are batch-fired and was wondering if that might have anything to do with it.

i think the batches are 1+2 & 3+4. a quick trip to madracki would tell for sure.

spark is 23 14
fuel is 13 24

I'd assume you are getting spark on all 4 since its running super as nasty rich on 2 and 3 and the way its batched....

so either you have 2 dead injectors, or two leaky injectors, or im completely wrong.

Leaky injectors would be a good explanation, but the fault in it is that it might not be that likely that both 2 and 4 started leaking simultaneously.

I just got the taillight too man, thanks!

Could you post your MSQ? I'd like to take a look and see if there are any settings for different fueling on the separate injector channels.

http://img256.imageshack.us/img256/1...eltablexd2.gif

im sure Matt speaks of this....

Absolutely, at work now but I will later for sure.

Curious where that goes. I'm wondering if something burned out in the MS, just leaving the injectors on. That, or a short somewhere.

Did it happen suddenly? Does it always do it, or is it on and off?

Here's the .msq \/

Abe: That's what I was thinking might possibly be the problem, but didn't want to jump to that conclusion lest it be something more simple.

It always does it, I can't remember when it started but it hasn't let up since I first noticed it happening. It's like clockwork; after startup, AFRs will be around 15:1, then climb to 17:1ish, then drop steadily to 11.5ish, sometimes 10:1 in cruise. Just measured my MPG - 16 MPG...

Oh, it doesn't happen for a while?

If you run it for a while, 20 min or something, shut it off then immediately start it again, how is it?

I wonder if it's electronics heating up....

post a log too. needs more log.

your ego settings and AFR table are screwy.


RPM Based ACCEL needs to be off.


ASE table should go to 0% at 160*


timing and fuel tables at idle look crazy low.


overboost is at -5.7psi, might screw things up.

Overboost protection looks like it's at 220 kPa to me.

I have PM'ed Kotomile about this - we will look into this one a bit more closely.

might be my settings, i have things is PSI where available..i had errors, so that was probably a bad conversion.

He's using RPM based AE, so don't turn that off.

He's NOT using EGO correction IIRC so it's disabled and the table isn't configured.

ASE is OK to have at 160, most cars still need some. It will decay and cut out completely over 30 seconds in the current config.

Yep, looks lean at idle. Yep no advance at idle. That stuff's changed since it was here.

Overboost appears to be at 220 kpa, he's boosting 14-15psi so that should be fine.


My suspicion was a short, or a problem with the injector driver. It was fine when it was here on the dyno-- but something's not right now... are you still in town man?

I admit I messed with the lower left cells in the fuel table and timing table since the dyno session, trying to get the car to idle right and not idle pig-rich. Of course, that didn't work, I replied to Matt's PM and I'm hoping we can work something out that doesn't involve too much downtime (for several reasons).

'Course, the msqs from the dyno are still saved, so I'll simply go back to them once the problem's solved.

Jerry - I'm in Augusta. If I could get some time next week, it might be beneficial to drive over (in the OTM.. 16 mpg in the Miata) if the MS can be diagnosed or exchanged in one day.

The process I described (stoich, then lean, then rich) takes all of 10 seconds. If I shut it off when hot and restart it goes immediately back to idling rich.

The two in the first post are pretty typical presently.

I'd load the old msq, just to make SURE it's all ok. Might even reflash the code, though I doubt that's the issue.

Can you open the case? See how things look? You might run the car for a bit (or on the stim) firing everything, and see if anything gets hot. Touch the chips, if you burn your finger, something's wrong. :-)

It's already on it's way to Jerry and Matt :)

Matt ran it through the tests, the MS is working fine...

So now, I suppose it's time to de-loom my wiring harness and look for shorts. :vash:

And just because it can't hurt, I'll try reflashing the firmware too.

If they tested the MS and it's fine, DON'T CHANGE IT. :-)

Get to the wiring.

BTW, in the test, did they run real coils, to see if it gets hot, or just run it on a jimstim? No current draw there, so it would test fine but not show a near-death componant.

I'm not sure, that's more a question for Matt Cramer.

We ran it on a bench testing device with live injectors first, then on our own turbo Miata.

Does about narrow it down, doesn't it?

Er, there's no low ohm injectors on his car, is there?

Anyway, wiring seems the reasonable place to look.

Driveway is covered in 15 year-old coiled electrical tape :)

no leads yet, but dammit I'm gonna find this short.

No low-ohm injectors here Abe! I run red-top 460s.

I must've found it, all I really found was a couple shoddily taped up connections from my bipes uninstall. No more Subie idle, and AFRs are around 13.3-13.5 at idle. Cool!

Congratulations! Faulty wiring will get you every time.

I owe you and Jerry a debt of gratitude, you made room in your busy schedules to diagnose my working ECU and shipped it back without complaint.

Hey, awesome! Congrats...

Thanks, I'm glad this wasn't like my last wiring issue, which took months to fix.

I'm kicking myself, however, for unwrapping all the wiring harness in the passenger side of the engine bay before thinking to look in the footwell..

..at least I got shiny newly-wrapped wiring harnesses out of the deal.

Well, I thought I had this licked, silly me.

Pulled the plugs just now after running for a few days on the COPs, and the same symptoms are on the plugs, except now 2&4 look about right and 1&3 have a white looking ground strap. So same problem, but now leaner! It's not running rough like a boxer as it was before, or spewing black smoke from the tailpipe, but this is just as scary, or scarier since it's leaner. Hopefully I can get these pics up...

Could the injectors being grounded constantly like they were before have damaged them in some way? That's really all I can think of, if they were still stuck open I would certainly have the same boxer idle and black smoke (and constant >11:1 AFRs) as I had before. Should I try moving the injectors around and see if the problem follows them?

Moving the injectors certainly would be a good quick check, so I'd try that first and see what happens.

To answer the above question... You certainly can damage injectors by locking them open (grounding them out) constantly and overheating them. That's not to say that's definitely what's happening but it stands to reason as a possibility. Swapping them up as Matt mention could help to determine if this is the case, or (what would be safer) sending them off to be serviced would check their flow rates and make a sure determination if it's the injectors. Downtime sucks, but not as bad as a popped motor...

If you do send them off, you might mention that they were the victim of a wiring problem and a couple of them were grounded out for a bit. They might run some additional tests....

Unlikely, but you COULD measure the resistance across the injectors - also you could have damaged the drivers on the board. Or maybe your wires just got hot, shorted.

Keep us posted!

hey did this ever get resolved? I am having the exact same problem right now. Car is a basically stock 97 and i am using the Braineack parallel install harness on an MS1v3. What is strange is that when I initially hooked it all up, it ran great with no tuning on the mspnp fuel+spark settings. Pretty much ran 13afr at idle and 14 - 15afrs cruising around the block. After that, I hooked up the WBo2 wire and fastened the case to the car, Then when i try to restart ... runs "like a busted subaru" and then I pulled the plugs and cyl 1 and 3 are black and 2 and 4 are white.

haha! Scott, learn how to solder (just kidding, your doing just fine)! I almost loled when i took a look at the wiring harness, one of the fuel injector wires had come undone, and therefore there was no fuel in two cylinders. Hooked it back up and I am back in business. Now I have an LC1 that actually works, and I am officially running megasquirt (again). Still need to work on the sensor bias settings though, AITs are reading about 30* lower than they should be. Oh well now it runs.

Yes, I hope.. I sent the injectors back out to Witchhunter for testing and they said they were fine. When they came back my brother reinstalled them (a few months ago) and everything seemed to have cleared up. Weird, still don't know what caused it.