+1. Slack cable can cause loopy idle on a stock car.

IACV is not hooked up guys. It shouldn't even be running - same for the TPS activity in the logs, I don't have a TPS hooked up.

I'll definitely check the throttle cable when I get a chance.

It does this if I use the stock ignition OR custom harness, stock coils, COPs, stock fuel injector OR custom harness, RX7 550ccs, or the FIC 650ccs.

why not? (ill review the msq when im home, cant here)

but tell me about the AFR weirdness after you crank.

I run a NGK AFX, Brainy. For the first 20 seconds after crank, it gives invalid data because it is warming up the sensor. I keep getting tempted to throw the RX7's LC1 on the Miata, but I really don't want to tear into the RX7 right now if I can help it since the Miata is torn halfway apart, and it'd mean I have no car.

The IACV on the 1.8 doesn't work/is generally busted.

i think first off you should manually open the idle valve a bit, maybe clean the butterfly while you are at it.

no logs i looked at seemed "good" hard to tell by looking at data only, ya know?

The manual idle valve has been opened a fair bit to an extent where it idles at ~950rpm when it is warm. Should I open it even further, Brainy?

I'll clean the butterfly today, as well as order the FM 1.6->1.8 throttle bracket.

that's odd it idles so low when "cold" then.

I've never idled that low when i've run without a valve and my adjustment screw was only partially opened.

I had to max out my previous 1.6 idle valve to even get it to idle at all during warmup. The only thing the same between the 1.6 and the 1.8 build now is the MS2 and WB (Sensor has been replaced on the WB) :( - even the wiring has been replaced (Edit, at least between the MS2 and the sensors/ignition/injection/etc., obviously I didn't replace wiring on the interior for things like blinkers :P)

your junx is busted.

Well, Brainy, at this point I don't know where to go with "your junx is busted".

At the behest of various posters, I've been through two engines, several sets of sensors, I've custom wired from the MS2 harness that you made forward, I've tested/checked/tried everything that people have suggested. I've replaced everything in the car at this point that is tangibly related to it running - including being at 3 sets of injectors at this point* and an entirely new ignition system as well as running two separate coil packs from different years.

All that I haven't touched is the MS2 and MS2-specific harness, which I had sent to you about a year ago now to get working, and the WB controller.

(Edit) I've gotten most everything worked out, except then it went to all crap when I tried moving over to the XS3922's. Sure, the idle was a bit rough, startup was a bit touchy, but it all worked, then just changing over to the XS3922's made everything revert back to how it was months ago :(. I don't know if it's plug-specific, or if it revealed an underlying problem somewhere.

*: Incidentally, one of the sets of injectors worked perfectly for another poster - he didn't even need to clean them. One of the coil packs I sold also worked similarly perfectly for a poster.

Justin,

You have a PM.

Any spare parts you want to send us for testing we will be happy to check out. We have an ASNU Fuel Injector test stand here as well as a coil and ignition module tester and can scope out most of your parts. (FWIW, we are a sister company to Wells Vehicle Electronics/Airtex).

I somehow get the feeling that without putting an oscilloscope on the car with transducers to measure the running compression/scoping the valve events to rule out any valve/cam timing issues we will have to assume that there is some kind intermittent in your wiring or some EMI causing problems. I'm sure we can rule out any fat fingering in the calibration and I would guess you've checked to see if you have enough current for the COP's/Injectors.

There has to be a shop that can do the test near you for a small fee.

This is a picture of what I mean:

https://www.miataturbo.net/attachmen...ine=1335465372






wiring or setup that's causing problems

under injector characteristics, turn pwm current limit to 100%

has the trigger angle been synced? it's set to zero.

warmup enrichments need to end at 100%

turn off idle advance

Done

I leave everything 0'd out and set to 10 in MS, and then set manually as per FSM. I cannot get the idle to change wrt the timing light when I adjust it in the MS. Does this point to a potential problem?

Done

Done. Thanks Brainy.

are you saying you haven't been able to sync trigger angle to CAS output?

or that you locked timing to 10*, set trigger to 0, then adjusted CAS?

Latter. Nothing I do wrt trigger angle offset changes anything, so I just leave it the eff alone and adjust timing as per FSM.

Same thing happens to me when I try to adjust the trigger angle.

Well it adjusts, lines up perfect, then when I hit burn the ignition angle is off again by the same amount yet the trigger angle has changed xxx degrees.

any updates bro?

Same here on a friend's 91. Open trigger wizard, get something like 20 degrees off with offset to zero, set offet to 20, marks line up at 10* on the pulley, hit Burn and bam, 20 degrees off again.

What firmware are you on Richy?

None, was too busy yesterday to be able to work on the car and/or weather was absolute ---- in the little time I did have.

Hopefully I'll be able to put some time in today, and hopefully nothing will interfere this weekend for car working ons.

i think the current limiting on the injectors might be the issue.