joshuaho96

I'm a big fan of more advanced modeling so it's easier to constrain the problem and there's less opportunity to shoot yourself in the foot. As OP mentioned you know when you're really screwing something up when working with a VE model if the numbers don't make any sense. 100% VE at idle for example. X-Tau constrains the problem of transient throttle such that you're only picking a wall-wetting constant and time constant and everything else just flows out from there. If your wall wetting constant or time constant is some ridiculous value you know you're doing it wrong.

I guess the correct distinction is VE vs injection time, regardless working in injection time is just kind of a pain. It's kind of like old style transient fueling vs x-tau.

I'd have to look at the series 2 in specific but when I worked with the EMS-4 in AEMTuner it did not work in speed density. Yes it uses manifold pressure as a load signal and there is an IAT/CLT sensor that is used to adjust fueling but all the tables ultimately operate in raw injector pulse width, it has no conception of volumetric efficiency.

Did you actually inspect everything under the plenum? The area at the back of the engine is a mess of coolant pipes. There's a Y-pipe for coolant return next to the wastegate vacuum pipes which can pinhole leaks from corrosion or mechanical stress cracks the weld/brazing for the joint. Also the rear block fitting for coolant could also leak. It also has a Y-pipe as well. As others have said it is also possible that the core plugs have corrosion so they're leaking coolant as a result. You can try to fix it with RTV but getting access especially for the back of the engine will probably require engine removal. Edit: Pic to show what I'm talking about:

Weird to me how the mechanic didn't offer to just tear into it further at that point but that's just how it rolls with a lot of mechanics. They'd rather get the cashflow sooner than later.

AEM hasn't even supported the series 2 in a very, very long time. To my knowledge it doesn't even support speed density. AEM has completely exited the ECU market as well. The last ECU they shipped was the Infinity and frankly speaking it was a buggy mess, the linked thread shows some things but my personal experience with it was not great either: https://www.miataturbo.net/aem-59/aem-infinity-piece-junk-lets-find-out-together-91346/

I have experienced what I would describe as idle dropping out in moments with counterfeit spark plugs but it wasn’t really idle hunting. It felt like a misfire almost. It would drop and then recover as the idle control caught it. Never stalled but noticeably felt strange and was fixed with new genuine plugs.

If you want to run the stock regulator you need to keep some method of making sure you aren’t trying to flow 255lph of fuel at idle. Otherwise you will experience what you’re talking about.

Idle hunting is a sign of air leaks. It usually means the ECU is trying extreme measures to stay on target idle speed. Easy way to validate this theory is to unscrew the TPS adjustment and tweak it ever so slightly to bump the TPS voltage above idle. This will disable idle control. An engine without vacuum leaks either internal or external should experience a low idle or no change in idle when you do this.

What a weird thing to scold people about. Don't decat your car or delete critical emissions equipment (PCV, charcoal canister) but as far as CO2 emissions go an old car driven maybe 5000 km a year is not the problem. It's rounding error compared to all the other things that climate scientists have inventoried that are actually a real problem.

I was just going off what that post mentioned, which is the early AA100 was still plastic compressor, then all later revisions were alloy. It's good to know that the risk is lower on the single turbos but still it's definitely a day-ruining event if a turbo lets go.

RB25DET vs DET NEO have different turbos. This thread talks about the differences: Personally I would not run these turbos without replacing both the nylon compressor and ceramic turbine. It will increase turbo lag but that is fine if it means there's no risk it sends ceramic shards backwards from internal EGR or a bunch of compressor chunks through your intake tract.

You had the same idea I did. If that doesn't do it start measuring pressure at various points in the system, the pressure drops at each point will tell you where the restriction is. Could be an FPR too. If you've hardwired your fuel pump to run full blast all the time the FPR is almost certainly your problem at idle. Nissan used the FPCM to slow down the pump at idle.

I have E85 locally, the US loves subsidizing corn and corn ethanol. Also we've banned basically every other octane booster at this point so ethanol is the only thing that you can get for a reasonable price. I plan on doing flex fuel eventually.

Basically everything you described + the annoyance of keeping all of that stuff working is bad enough that as much as I'm in love with the idea I can't bring myself to actually do it.

I was thinking more about modifying the ROM or circuitry on the gauge cluster instead.

Is there a better way to do this? If people have figured out how to modify the odometer on the cluster module surely it must also be possible to figure out how to recalibrate how it correlates output shaft speed on the transmission to speed/distance.

The sound you're hearing is the shift interlock device. You have to press the brake to shift out of park. There is a stop lamp switch in addition to the little rubber grommet. Test the switch and see if it's working as intended. A new one is pretty cheap.

It's DBW. Easiest place to start is make sure the throttle body isn't clogged up too badly. Long term fuel trims will also give some idea of what's going on.

The specs for this stuff is in the factory service manual. If the source for the play is in the rack itself then you will need to remove it to adjust the preload. Steering play can have many sources. Make sure it is actually the rack before you go through the effort of removing it.

Vinyl vacuum line caps should work. Even if you manage to get it in before emptying the reservoir I would do a full flush including ABS bleed afterwards.

Whiteline is probably fine for the subframe, technically I believe Nismo USA is selling solid aluminum subframe bushings these days which is a step harsher than that. Again, this is a question of what you care about. If you want "purity" then I'm pretty sure Nismo is actually the only option for "OEM", looking at the OEM parts catalog they don't break out the subframe bushing as a separate part. 55442-RS580 should be what you're looking for.

Also, checking the front turbo is not that useful. Usually the rear turbo is first to blow up.

I really don't get it anymore, even accounting for currency fluctuations Amayama is often more expensive than US dealers for the same parts these days.

You sure it wasn't NATS or something?