Got a 1995 240sx with an r33 rb25 gts-t. Wiring was done by Mckinney's Motorsports. Anyways, upon the turning of the key, the temp gauge inside the cluster shoots all the way up! I have checked for any crossing of the wires near the sensor area but nothing. Is there anything I can do to fix this? I would like that gauge to work...would be rather pointless if it stayed malfunctioning.

Another problem is the z32 MAF plug and wiring. I been talking to Mck and have checked online for diagrams and what not. Found some that looked real good. I corss checked them with other sources and tried. The car then would either start and then die or would idle funny like it was running without a MAF. I have a S AFC II which was wired by Lightspeed and set for the z32 MAF to RB25. I am not sure what to do. This is my last obstacle before I can run the car.

Thanks for any help.

 

Temp gauge is 240SX cluster and RB25 sensor? If so they are NOT compatible. You gotta use the 240SX origional temp sensor. It WILL go in place of the RB one on the lower intake mani. The one wire sensor is for the gauge. Leave the 2 wire sensor alone.

are you 100% sure that the wiring for the MAF is correct? McKinney doesnt wire it for that MAF and if you dont get the wires right you will be in trouble. Getting them wrong will burn out your ECU.

Where you live, I am in Albany, NY and might be able to help if you are not too far away.

 

Unfortunately, I live in Waco, Texas. Thanks for the offer though. I believe the wiring for the maf is correct. Been messing with it for the last couple hours. I had it to where it would just boost straight up to 8k and then I would shut it off. Checked for leaks and such. Switched things around and then somehow I got it to idle at 800ish but it was REALLY rough. Gave it gas and it would only rev to 4k. This is where I am stuck at now.

 

Oh, for the gauge thing. Are you saying that I get the KA temp sensor section and splice it to where the rb sensor is connecting to?

 

Go buy new NGK V-Power spark plugs for the 300ZX TT. Gap them to .8MM and install them. That should fix your rough idle problem and cost around $13. The RB motors LOVE copper plugs...down side is you gotta replace them more often than platinums.

The KA gauges need the KA sensor. The wiring on the RB harness is fine to attach to the KA sensor.

Find the 2 sensors in the upper rad inlet on the intake mani on both the KA & RB motors

Yank the one with only one wire coming off them, KA first...then RB...DON'T MIX THEM UP!!!!!!!!

Install the one wire temp sensor from the KA motor into the RB intake mani.

Plug the RB harness into the KA sensor.

Done-gauge problem fixed.

 

Went and got some double plat NGKs. They didnt have the copper. Gapped them to 8mm. Installed. Idles rough still. Feels like it isn't getting enough fuel. Won't let me rev past 4k still. Could these problems be to not having an pgraded fuel pump? My 255 walbro is still in my other 240 and have yet to be taken out. After letting go of the gas, the tach needle goes down past the idle point and feels like it wants to die.

 

Got it working. Turned out that when the swap was being done, the s13 throttle cable wasn't swapped out. Thanks for the help.

 

Went and bought the single wire temp sensor for a 240. Took out the rb sensor and screwed in the 240. Plugged it in. The temp gauge is still shooting to max. Did I do something wrong?

 

Make sure that the blue/black wire isnt grounding out to the body somewhere.