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-   MEGAsquirt (https://www.miataturbo.net/megasquirt-18/)
-   -   Idle viiiiiibration! (https://www.miataturbo.net/megasquirt-18/idle-viiiiiibration-64956/)

hustler 04-14-2012 02:23 PM

Put the jack in various places, just to rule out contact somewhere.

How do you not have a phone that makes video?

blaen99 04-14-2012 02:26 PM


Originally Posted by hustler (Post 864349)
Put the jack in various places, just to rule out contact somewhere.

Jack in every place I tried results in the same vibration. And I do mean...every place


How do you not have a phone that makes video?
Oh, I have a phone, but it has shitty resolution. I'd prefer you guys be able to see the video much more clearly - it's uploading to youtube now as we speak.

blaen99 04-14-2012 02:37 PM



Video as requested, wait untill I get to the rear window to see it. I couldn't keep the cam still enough to demonstrate any other shaking point, I'm not pro like SHOES.

The vibration at idle drives me nuts. :( Seriously, the ENTIRE CAR is shaking like that.

The idle is even harder/harsher than my RX7's idle with MMR mounts (Read: Solid bolt through). I strongly think it has something to do with the ECU, 'cause I've gone through for about the fifth time this morning checking all clearances - everything is correct mechanically, and except for tranny/driveshaft/diff/axles, everything else is gorramn new in the engine bay/drive train at this point.

blaen99 04-14-2012 05:11 PM

All right, I'm officially at wits end mechanically.

Unless I replace all bushings in the car, I don't see any way this could be caused mechanically.

When I first start it, it vibrates so hard you can see the side windows shake a good inch or so of movement at first. As it warms up, the vibration gets less and less worse.

I don't get any increased vibration with increased rpm. Actually, when I'm moving, the vibration is less worse than at idle.

This even applies if I drive it when it's cold (Bad idea, I know). Seriously, the vibration is less worse when I have my foot on the gas when it's cold vs. let it idle stopped.

I don't see how it could physically be mechanical - higher rpm should mean more vibration, not less. Short of it being PPF alignment, which I eyeballed, I don't know wtf it could be.

Faeflora 04-14-2012 05:53 PM

naw it can also mean that the vibration is "smoothed out".

bushings are not the problem.

post vid of engine bay vibrating. AND WITH SOUND. also rev it using the throttle plate while video taping.

blaen99 04-14-2012 05:55 PM


Originally Posted by Faeflora (Post 864420)
naw it can also mean that the vibration is "smoothed out".

bushings are not the problem.

post vid of engine bay vibrating. AND WITH SOUND. also rev it using the throttle plate while video taping.

On my way to do that very thing.

Techsalvager 04-14-2012 07:33 PM

what motor mounts do you have?

Techsalvager 04-14-2012 07:38 PM


Originally Posted by blaen99 (Post 864403)
I don't see how it could physically be mechanical - higher rpm should mean more vibration, not less. Short of it being PPF alignment, which I eyeballed, I don't know wtf it could be.

incorrect, the stock engine will be in worse balance between 600-1200-1800 rpms and vibrate the most. Over these rpms it will be fine and smooth out. I know from experince and my friends at the machine shop that works on cranks and blocks.
Also at motor without a idle valve will idle lower at cold by 100-300~ rpm vs when its warmed up, so you maybe near 600 rpms or so cold and 800-1000 rpms warm, and trust me just those hundred rpms make a huge difference in the vibration the motor puts out.
I've dealt with MMR mounts before on a miata, not again unless race car.
if you have stiff mounts in the rear it will also transfer in vibrations too.

blaen99 04-14-2012 08:23 PM

Finally got everything worked out.

Fae, you sir ------- rock. I said ---- the AFRs, tuned by ear and smell just like you said. I got the sucker.

The only thing left is an occassional misfire at idle. But an occassional misfire is no problem.

P.S. ---- the AFR. ---- it hard.

Techsalvager 04-14-2012 08:29 PM

what is your injector PW at during idle?

Faeflora 04-14-2012 08:31 PM

http://tnvalleytalks.hoop.la/fileSen...od%20-%201.jpg

blaen99 04-14-2012 08:33 PM


Originally Posted by Techsalvager (Post 864476)
what is your injector PW at during idle?

5.7 req_fuel with a 48 in the relevant table.

I'm gonna play with the timing and fuel a bit more Fae, but yeah. As soon as I said ---- AFRs, it all went together pretty well. Thanks again man, this made it a very easy solution.

blaen99 04-14-2012 10:54 PM

Took it out, drove it, did some tuning.

---- yeah boys, this is working well.

The EV14's get the Blaen Seal of Approval. Great set of injectors those are, can't speak highly enough for them. The COPs are great too, for that matter!

blaen99 04-24-2012 08:36 PM

Annnd it's back.

https://www.miataturbo.net/showthrea...147#post869147

Swapped in those plugs, gapped to what the manufacturer guys recommended.

Now it idles like absolute dogshit (And vibrates so ------- hard), with near-constant misfiring - previous idle problems were caused by misfiring incidentally. Partial throttle is dogshit, tons of misfiring or hesitation. Decel is dogshit, tons of misfiring or hesitation. Acceleration is the best I've had it yet on the Miata.

What do?

Faeflora 04-24-2012 08:41 PM

You suck. Check your AFR bullshiit again.

Richen up the bith.

I have no clue what those plugs are but maybe some wackass flamefront wierdness happens under full load that don't happen under weaksauce load.

Anyways richen up and shiz

blaen99 04-24-2012 08:44 PM

Tried richening and leaning Fae. I'll go try it again in a bit, however, this also happens under partial throttle, cruising, and decel - not just at idle.

elesjuan 04-24-2012 09:29 PM

I wanna throw something out there;

When my car was first running on MS something caused a CPU reset (power failure or something) that totally bombed my firmware. Thing started running like complete ass in the strangest ways and as a last ditch I reflashed the firmware and that solved it. Worth a shot maybe?

blaen99 04-24-2012 09:29 PM

Thanks Eles, I'll reflash firmware right now.

BRB.

elesjuan 04-24-2012 09:59 PM

:fingerscrossed:

blaen99 04-24-2012 10:04 PM

Well, it fixed several things I've been having problems with.

Hell, the goddamn AFR's actually match up perfectly now between tunerstudio and my gauge. Starting is so much better (SO much better) with the new firmware, and it actually helped a little bit with the misfiring.

But it didn't solve it. It's still pretty bad. Should I swap back to my old plugs, and see if they don't have such large problems Ele?

(Edit) Yeah, holy ----. It solved a ton of problems I've been having with various bits and pieces, but it didn't solve the misfiring problem.


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