RickJeeter

Hey Guys & Gals,


My friends call me Rick. I've owned a 99 Miata for a couple years now. It's a 286k mile Miata on its third engine. I recently purchased a 97 Miata with some minor modifications. For starters it has GC Coils, FM Adj. Sway Links, FM Sway Bar (Front), Torsion Rear End, Etc. The PS has been removed from the accessories and the cockpit has been fitted with a Oil Temp Gauge, LC1 WB and a Vacuum/Boost Gauge. The engine is a Turbocharged 1.8L fitted with MS2 ECU, while still using the factory ECU to run things such as IACV. The shortblock consists of 9:1 JE Pistons, CP Carrillo Rods, and King Bearings. The 99 cylinder head is fitted with a stock Intake Manifold & a Begi Gussetted/Reinforced Turbo Manifold with a 2871R Turbo. Fueling the engine is four either 525cc or 550cc Injectors (I'll double check tomm.). The MS2 is all installed and the car runs. The boost controller is currently set at 14 IIRC, it is an electronic setup. It's only a 2 Bar Map Sensor. The exhaust is a full 3" SS with a Magnaflow Muffler connected.

Well I am not very familiar with the MS and have been doing research. I definitely need to get the idle tuned out. Right now the idle is low (500ish) and dips (250ish), I noticed that if I stop on a big slope that the car will want to stall. Today I jumped the Ten and GRND and bumped the idle screw. Brought the car to a solid 950-1000 RPM. I do know the system is setup for batch fire, not seq and it is the factory Coil Pack and wires. When the car cranks it is a tad lean (17-19 AFR) for just a short blip or two and only at idle. After it is warm (Oil Temp Wise), the AFR seems about normal maybe a hair rich (12.4-14.6 AFR). In any gear when I go light throttle the AFR seems to dip down to about 9.4 AFR, then it picks back up and boogies. So far that's all I've noticed by just watching things, no data logging yet. I'm not to sure how to do it, but I'll just google it. I just downloaded the TS and MLV.

Along with the Tuning of things the Oil PSI is a tad low. The Oil PSI once warmed up is really low and inconsistent. 3 PSI @ idle one day (Hasn't been this low since bumping the idle up), then 7 PSI the next sometimes even as high as 14 PSI. While it does a consistent 27/30 PSI @ 3K RPM. I need to hook up a mechanical gauge and see if my readings are any different. The oil pressure sender is the correct 2"x3" one (which looks a little worn) and the gauge itself in the cluster has been swapped, I presume. The motor has very low miles on it and also features a Boundary Engineering Pump, so for what it's worth I'm hoping that there is a little problem looking like a big problem.

Hopefully I can find some help here and if anyone has any questions please don't hesitate to ask.

Thanks For Reading,
Garrick "Rick Jeeter"

sixshooter

iTrader: (12)

Welcome to the forum, Rick. Running the MS2 as a piggy back to the stock ECU is a highly unusual arrangement these days. Are you subject to smog inspections? If not I would suggest running the MS2 as a standalone and using it to control your idle mixture and timing. This will also help you with the tuning that you need to do to make your car run right. Going rich on throttle tip-in is just a matter of tuning.

RickJeeter

Thanks for the quick response and the help! I actually got lucky and don't need emissions, imagine that. I haven't a clue where to start as far as converting to full stand-alone. The PO did need to be able to pass emissions yearly but we just pulled the engine and chunked the stocker back in, along with the factory exhaust.

sixshooter

iTrader: (12)

It's probably got a jumper harness connecting both ECUs. Post pics of the connections for us.

RickJeeter

Can do. I tried using the tinypic site for resizing photos. It did not work. What are some other places y'all use? Jumper harness sounds right.