1990 JDM Z32, new Nistune, 550/615 swap, Idle hunts.

[Chaddoes]

Hello Everyone,

I usually watch from the shadows as I can search and find my answer on my own but I figure I would finally give posting a shot.

To make a long story short, I purchased an recently deceased man's project car.

it was a full puzzle car, no engine in and two partially built engines and 2 transmissions came with that car.
(yay spare parts!) all unknowns.

I am on year 2 of this project, and I finally have an engine built and in the car. (engine in and out 3 times before finally giving in a doing full rebuild)
I am afraid that I may have done too many changes and deletes to make things work smoothly in my favor.

I have done every delete recommended, and during the engine rebuild, I have increased the injector size to the yellow nismo 615's along with a new fuel rail and matching new style / old style connectors and seals to make everything match.

I have an AT, and had to use my original ECU as the MT ECU's (have extra ones) apparently are not backwards compatible with my AT, so I socket-ed it and dumped my original base-map into nistune, I then used the injector resize to create two different builds (one is allowing nizstune to adjust all the maps, and the other is an injector resize only)

I then loaded them into a pocked romulator and did another consult dump, to confirm the romulator was running correctly and the dumps match %100.

I set the cas to 15 for timing, my MAF is .8v and has a cone filter.

Now to get to the point:
The car turns over, starts, revs up and dies 2 seconds later.

if I adjust the throttle stop, I can get the car to idle at about 1200 rpm.. it runs for about 10 seconds and then starts idle hunting. (throttle never shows full closed in consult when I use this method).
still learning how to tell if vehicle is running closed loop or not.

I did the Idle Air Control valve cleaning job with WD40 and tried adjusting it's screw both in and out.

The car doesn't change more then about 150 rpm when I unplug the IACV. (I will ohm it out tonight)

I sprayed brake cleaner around for possible vacuum leaks but haven't found any yet. (unless it's the plenum)

I am wondering if more work needs to be done in nistune such as injector latency.

This weekend I will confirm every injector is working as I just assumed as I bought them fairly new.

Thoughts?

I have no bad codes, I did the EGR Delete using plates and vac plugs, but no resistor, I cut out my exhaust temp probes for new aftermarket pipes (yes the full jspec JDM's have exhaust probes) not sure if I should put resistors there either, but like I said, no codes other then the all good code.

I timed the engine using tooth counts, as the back plates had separated and had movement and I couldn't trust them (timing marks).

-Chad

[Chaddoes]

[youtube]62j7kXhYBPY[/youtube]

I guess I'm to n00b to post youtube URLS, so above is the video ID.

[red coupe89]

Hey man, I'm in pretty much the same boat you are (although not with the multiple engine/trans) and I'm have the same issue with my new injectors. I'm also on nistune and have tried different latency and K constants. I've yet to get to the bottom of it but I did have a problem I itally with spark plugs being fouled. If you have time check and re gap, worth a shot!

[Chaddoes]

Hey thanks, good idea, the plugs are the ones that came with the car, champion iridiom's they where gap checked, re-gapped as well as checked for spark.

I think we re-gapped to 0.035 for the high pressure of the turbo.

I know they are doing something as I unplugged each one while the engine was running to test for misses.

Anyone think it would make a difference to switch to the NGK's?

I will check for fouling.

[red coupe89]

I've been on here for a little while an all I've ever read if factory plugs only. There all I run. They are the correct length to make sure the plug tip is in combustion chamber as opposed to sitting in the head. Depending on your boost level you may need to close the gap your running as well. Hope this helps!