Idling trouble... I'm miffed.
 

I've checked the obvious: Vac leak, TPS adjustment, etc etc. Now I haven't had the BAC fully hooked up (the solenoid wire broke) until today. I've gotten it to idle rock steady at 1000rpm which is exactly where I want it right now. But as soon as I hooked up the solenoid it idled just fine. Went about 100 ft and all of a sudden my EGT's started splitting (front rotor going about 200 degrees hotter than normal) and the oscillating idle started. Shut it down, checked it all, no problems found.

I then decided to adjust the idle and get it set and dialed in properly with the BAC fully hooked up. No dice. I get it to about 1500rpm and it still oscillates. I thought perhaps a vac leak, but I see no obvious leak. All possible locations on the manifold are capped off, or tapped for use with other vac/boost powered objects. I scanned over the charge piping and it's all tight and connected.

To make it back home I unhooked the solenoid that I just fixed (soldered the wire back in), and adjusted my idle to around 1000rpm. Everything's fine. The reason I don't want to leave it like this is that when the engine is cold it has a tendency to stall out, I would prefer not to heel-toe it to keep it running until it has warmed up.

Any thoughts or suggestions?

Of note I seemed to be having trouble with the RTek around this time, though I'm not sure if it's a symptom or a cause. The RTek 3D fuel map would give me an error of "unexpected table size" but if I checked under table all the values were still there. It was quite peculiar. Any thoughts/suggestions?

On the BAC - do you have a/c (are you using it and is the belt connected?).

Also - run a test on the BAC itself. If the valve is bad it may cause that as well.




On the RTek, not sure... I've never played w/ your newer version only the one you CANT edit anything on, lol.

Nope, not running air conditioning at all... I'm going to hate life this summer. I'll figure something out though... Something that you can't see but still blows cold cold air...

As for testing the BAC, I'm curious, test both solenoids? The one with the injector style connector and the Air Solenoid that mounts below it? Honestly that's the only thing that's changed is the one solenoid that sits below the injector styled one.

Ah - I dont recall the testing procedures for the air solenoid... but if you connected it and all hell brakes lose, and disconnecting it corrects the problem then I have to believe that something mechanical is bad or going bad, not sealing, etc.

Have you done a spray test? Connect that and let it do its funky idle and hit that area w/ some starter fluid and see if it sucks it in and smooths the idle out....

Pretty sure it's not a vac leak as it idles fine only when the electrical connector is disconnected. If it were a vac leak, it would do it regardless of the solenoid being active or not.

you get used to no AC in the summer, rock the windows low and keep the shirt off (for longer drives anyways)

When I hooked up my BAC, it started to run a little leaner and that caused the idle to oscillate like yours. I had to add more fuel to the map to get it to stabilize. Try doing that if you haven't tried already.

Nah, it doesn't even get to that point... but it does raise a possibility. I can't get it to idle anywhere under 1000rpm (12-1300rpm seems like where it wants to stay on a good day).

As for idle AFR's what should I be seeing? I did a really rough tune on the RTek and i'm seeing low 12's at idle and I think that might be really too rich since I am seeing smoke that seems to be a mixture of gas and oil being burnt off at idle (I don't think the oil control rings are bad because the smoke goes away intermittently and isn't smoking at all during cruise).

alright, the smoke is starting to concern me. Intermittently (more accurately after I come from a 60mph cruise at 2.5k) I see smoke when I stop and idle. The sheer volume of smoke is what is concerning me. The oil level itself is not affected all that much by the volume of smoke it looks like, but it does cause me to think it an odd occurrence and would like to remedy the problem as soon as possible. Could the smoke be caused by the oil control rings not being completely worn in yet (though, that would not make any sense since the oil control rings were installed on the same locations on the rotor they were pulled from).

Thinking more acutely a possibility is that the used rear iron I installed, and the old oil control rings have not completely worn to each other yet causing slight portions of oil at the increased oil pressure to squeeze by and thereby causing the smoke. This would account for the 40 deg F lower operating temperature I see at most RPMs for the rear rotor, and for the smoke. The only other possibility would be that the oil injectors are working overtime and dump in too much oil because of increased oil pressure and no check valve installed to avoid positive pressure on the vacuum lines.

Thoughts?

You're 100% positive that when you put the o-rings in the "scrapers", that none were nicked, twisted or otherwise? Were there any flat edges on the orings? Older ones tend to flatten on their sealing surface, and when torn down are basically impossible to get sealing properly again.....even if they were before.

EDIT: how many miles were on the re-used orings?

A used iron, and BRAND NEW ring and o-ring shouldn't smoke a peep at all. I've never noted any break in period for them before, but I always use new orings (or super-low-mileage-after-popped-seal-ones) The o-ring does more sealing then the scraper really with regards to crankcase oil getting out into the combustion chamber.

Increasing the crankcase oil pressure will have zero bearing on what the oil injector nozzles see......unless I misunderstood you there. So that won't be the problem.

Yes, I'm sure none were nicked, scrapped or flattened. They were new viton oil rings.


That's what I thought. The oil rings themselves were brand new without defect and installed with lots of oil on them to keep them that way. I find it hard to believe that the oil control rings could go bad only sometimes.

You misunderstand. I've turbo charged my naturally aspirated engine. Would installing a check valve on the air line that leads to the oil injectors remedy this problem or even pose a problem in the first place?

Ahh I see, yea it shouldn't be an issue.

But in my experience, viton o-rings have been hit and miss. Mostly due to size variation.....but the one's I've seen fail or smoke, due so in short order. Not saying thats your problem, but I *have* known them to be a mix bag.

EDIT: Another possibility that happened to a local member here last year, involved the springs. He'd instaleld one backwards, which allowed the assembly of ring and scraper to turn on the rotor instead of locking it down with the tabs on the spring. Are you positive that they are all facing the correct direection AND oriented with the flat tab UP, round tab DOWN?

Yes. I made doubly sure to seat the springs correctly. Ensuring that the rounded end was sat directly into the divit/hole as per FSM instructions and aligning the tabs on the oil scrappers to mate correctly on the springs. Then installed.

Well, nothing much to do but keep driving and see whats beign burnt. If they're all installed correctly then there shouldn't be any porblems.

What about the turbo? What did turbonetics recommend for a restrictor given the oil pressure you're running (not sure if you've bumped it up or not)

I believe the restrictor is built in to the fitting i'm using. But I'll ask.