Tepm gauge fluctuates down, and rpms seem to fall.

[dtuner]

Ok, here goes. I have recently (may 2009-ish) rebuilt a 95 S14 with a KA24DE out of i bellieve a 93 S13. Everything ran fine after the first 3 test runs, except for minor clutch smoke because of residual anti rust coatings on the new flywheel. Months later the vehicle fans were interfering with the ac lines and power steering line started to leak. No big deal. Most issues are fixed, still have to do the steering and the speed sensors, but now it has other issues.

To have an idea, i will include the entire rebuild list. Here goes, Jeff if you read this and i miss anything please let me know.

KA24DE from S13, keps same distributor and main components from that engine, fully torn down (bottom end pressurized fine, so pistons were not removed) and rebuilt with Cometic HG, ARP Studs, Mishimoto Radiator, 60 Celcius NISMO thermostat, Mishimoto Fans, auxillary fan controller connected to factory temp sensor, manual swap with full hydraulics and steel braided lines, fidanza flywheel and clutchmasters stage 2? (not sure), Aluminum driveshaft, Cold air intake, 3" Cat and cat back exhaust...

Now we have a minor issue. The temperature on the gauge inside the vehicle (stock dash gauge) goes from 50% (if C is 0% and H is 100%) to 25%. and the idle seems to jump from 1k down to 750 RPM. Sometimes it seems to want to stall. Unfortunately i do not drive the vehicle every day, it is my brother's car and i hate to see him having issues. Please, anyone with insight let me know. I'm racking my technical knowledge and can't think of anything but air bubbles and MAF or IAC.. Maybe i'm spent teching my weber-carb 2TC all the time or my VQ30DE...

Thanks guys, you haven't let me down yet!

[Doya]

What ECU are you using.

[Azrial]

Is it dying down when the fans kick on? It sounds like you are putting to much of a draw on the electrical system. That's my first thought. I would check that and then go from there.

[dtuner]

ECU is stock from 95... automatic though. Never had an issue on manny swaps there except the auto shift codes.

All power draw is within limits and under flull load charging at 75A and 14.3V...

Still checking.

[Doya]

'95 and up ECU's are OBDII, '94 and down are OBDI. You need to use the proper ECU for the year motor you have.

[dtuner]

'95 and up ECU's are OBDII, '94 and down are OBDI. You need to use the proper ECU for the year motor you have.

Why? What basis? All the sensors and housings and manifolds are swapped to maintain all sensors and switches from the original engine. The only thing i used from the new engine was the main internals... Block, Head, etc.