First start datalog. Anything wrong?
 

I recently got my car up and running again after blowing the motor and then using the wrong IM gasket. I am very weary to drive the car now because I am not sure if the conditions are safe and I would really appreciate it if somoene can go over my datalog (at idle with a few throttle blips) and let me know how things are looking. I am using a Stratified built MS2PNP.

The one thing really bothering me is that the IAT sensor seems to be reading ambient temp. With the coolant temp is at 180* and the IAT is at 47*. The sensor is located right after the intercooler on the exit pipe. I tested the sensor with a blow dryer and it is working.

Another thing is the AFR. It seems to get lean when I apply some throttle. Shouldn't it get richer?

EDIT: New datalog attached after I made some small changes (calibrated wideband sensor and TPS).

UPDATE: I attached a datalog from today.


Thanks in advance.
Vasken

Looks like it's running extremely rich (in the upper 10.x range) for most conditions. Turn on auto-tune and drive it around awhile and see how it feels.

If your IAT is reading ambient temps just after the intercooler then it means the intercooler is doing it's job.

Not sure what you mean by going lean, there's only one instance of semi lean-ness in your log at 16.3 AFR, ideally you should be hitting 14.7 under light/medium load conditions, and 12.5 or so under full (non-boost) throttle. Go auto-tune for awhile. Once your VE table is calibrated better you can start worrying about acceleration enrichments.

How should I drive it? Grandma in the car, autocross, somewhere in between? And how long, 5 minutes 20, 30? Thanx

Im surprised the intercooler is working so well even when the car is stationary.

A few blips won't build any boost/ heat. 47 may be a tad cold on a heat soaked engine, but it takes a a few good hard pulls to start reading warmer

If the iat isn't working, a long as it reads colder than actual MAT, it will run rich, possible even stupid rich. You can run a heat gun at it ( just don't go too hot) and see if it changes.

If the IAT is wrong, VE tune will be worthless, as it will set fueling way off. I would make sure my IAT is acting normal if you suspect it isn't. Normally gut feelings are pretty accurate.

You can always take it to a shop and get it tuned if you don't trust autotune yet

Double post

I checked the IAT sensor with a blow drier. It works.
The cold air definitely explains the rich condition.

I will drive the car lightly and see if the temps go up and the AFR straighten out.

EDIT: Just got back. The IAT actually dropped a little. The exit pipe of the intercooler was cold while the inlet pipe was warm. Stupid intercooler cooling shit down.

I ran autotune for a while and the AFR is much better now. Its in the upper 14's at idle.

My boost gauge isn't responding so I need to check the lines and then make sure I dont have a boost leak. I have a tester somewhere.

Is it a boost only or boost vacuum gauge?

Its a boost/vacuum gauge. It doesnt seem to move when I start of turn off the car. Ill change the location where its mounted on the IM. I have it underneath right now.

Any clues as to why my idle is at 1300rpms?

Vacuum leak? Likely since you just reinstalled the motor.

Even more likely if you hooked up a boost gauge and it's not doing anything!

When it's warmed up, unplug the IAC ( green plug- year dependent ) of the throttle body. If the idle changes, you may have idle tunes wrong. No change, then vacuum leak, or the idle air on the throttle body is set wrong. With the IAC unplugged, if it holds 1300 rpm, try adjusting the idle speed screw in a bit, if it controls the idle then you prob. Just needed to change that. If it takes a lot of adjustment to change the idle, or, you can't change it, then assume vac. Leak.

I had better luck when the idle screw would hold 700rpm, then let the IAC control closed loop idle at 850rpm (tuned)... Then my IAC stuck open so now it's disconnected, and I use the throttle body idle speed screw, and have tune idle advance and VE at 700 rpms to pick up extra load. It occilates a bit, but is pretty stable

Thanks for the detailed response. I'll try playing with that tomorrow.

However, today as I was driving the car around nice and easy with the coolant temps at around 200* and the idle dropped actually hit around 900's. It doesnt stay there though after restarting.

Boost gauge is good now.

I added a new datalog from today in the first post.

What temp does your coolant fan come on at?

The load coupled with heat soak can cause the idle to drop if the IAC isn't holding that 1300 rpm idle.

Disconnecting the IAC takes just a second. If that's where the issue is, idle will react immediately.

If you attach your current tune, it'll help diagnose any issues as well.

You really shouldn't have coolant temps that high. Not in NYC during the winter at least. Possible with a 190* thermostat I suppose, but that's not ideal. Double check that the cooling fan is working, your coolant is topped off, etc.

Also, for the autotune, your question was never answered. Drive all over the place. You want a mix of driving conditions, including changing the load, rpm, and throttle position. Different gears help too.

There are bigger problems than it seems I think.

My fans turn on right away when I turn the key to ignition. So i had unplugged them. When it got around 200* I pulled over and plugged in the fans. They did not turn on. It seems like they are on when they are supposed to be off and off when they are supposed to be on. I did a quick test and unplugged the relays while they were on and they turned off. The therm sender in the back of the block is brand new. The thermostat is the one that comes with the Mtuned reroute kit which came with a 190* therm. Should I switch to 180?

Also got the car up to temp just now and unplugged the IAC. The car turned off. The IAC also buzzes loudly sometimes when I turn the key to ign and after I start it.

I dont know what any of this means.

Curly, thanks for explaining.

What are your fan settings? Can't help you too much, I just have mine activated with a switch.

I haven't touched any fan settings. Are they in megasquirt?

All we can do is guess at root causes unless you post your tune. Even then it can be difficult to tell what might be the problem, but it helps rule out a few variables at least.

Fan settings are in tunerstudio, sounds like you have it set wrong.

If the car shut off when you unplugged the IAC wire, then the IAC is the only thing that is keeping your car running at idle, and it is likely set wrong. It's somewhat important to get the car idling normally on its own, then letting the ms fine tune.

Google mspnp coolan fans miataturbo.net and it will pull up settings to use. After you get that sorted, plug in the IAC and get the car up to temp. Then go back the idle adjust screw out (I think) until you get a rise in rpms consistent and stable with each turn of the screw. Unplug the IAC at that point, and use the screw to set an idle of 700 ish rpms. Then reconnect the IAC and tune you idle. ( again google)

The car should idle without the IAC, the IAC is only to pick up loads etc.

What tune/map are you running with your MS?

The map is the base map from Stratified Auto (Alex) for the 96-97 Miata.

I will get the tune up here ASAP.

Thanks everyone.