Running rich - looking for sensor voltages

[S12_hybrid]

So my RB25det powered 1987 200sx is up and 'running' but its not running well..

Here are the facts:

-Series 2 RB25det BPU-Neutral switch is not connected.-Greddy intake manifold with Q45 TB (wired by hand - going to check tonight)-Just a downpipe for now-Maf sensor was wired by hand-Ignition timing unknown (checkinght tonight)-Fuel pressure is unknown (waiting on gauges)-MAF ground is grounded straight to chassis - not through ecu.

I fried the ecu that came with the motor - and i'm worried about this new one. It runs to motor, but if it were for a series 1 (I have a series 2) would it mess up the ignition? After all - there is no ignitor.

I pulled all the plugs and they are foul foul fouled! Even across the board. When driving - I can smell gas. I am also going to be checking the injector o-rings.. But it wouldnt make sense that the o-ring would cause SUCH a dramatic rich condition.

What I am looking for is specific voltages which should be read at sensors while the ignition is ON but the car is not running. This would help me check and make sure all my sensors are receiving the proper signal.

I am building a boost leak tester and will test for leaks tonight as well..I need HELP! This car is supposed to get me across the country in 1.5 weeks!!

Thanks in advance!

-Dan

[S12_hybrid]

Also my MAF is a 4 wire, with a Maxima style connector. I will get a part number tonight. My motor does NOT have an ignitor - hence will this maf work with the corresponding ECU?

-Dan

[Darius]

Your MAF will work fine as long as you shield the signal wire and wire it right. I don't think grounding the MAF to the chassis is right. I know for sensitive circuits, it is best to ground it at the same spot as the ECU to eliminate noise. There is a ground wire in your harness already going to the ECU, why don't you just wire it up to that??

Why don't you connect your neutral switch? I don't think it matters, but just to tie up loose ends.

Go buy a cheap in-line fuel pressure gauge to stick in your fuel line. It doesn't have to be anything more than $20. It's not like you will need to monitor it or anything. You are basically checking it for baseline pressure to see that your regulator is working properly.

Sounds a lot like me trying to get mine running right back in the day. I cut some corners and it caught up with me eventually.

[S12_hybrid]

I've got a prosport electronic fuel pressure gauge on the way - it's due today. I will have to consult some trouble shooting guides and wiring guides to figure out my neutral switch wiring and the MAF ground..

Any idea on the throttle valve switch? It wires into the TPS 12v+ and coolant temp 12v+ and then grounds through pin #57 on the ecu. If this circuit lacked continuity - would it cause issues with the TPS and temp sensor?

[S12_hybrid]

Anyone know the part number for the RB25det water temperature sensor? I know what works for the RB20det, but not certain if its the same...

ArrrggG!!

-Dan

[Darius]

It's in the parts thread in the stickies. I don't have it in front of me.

[S12_hybrid]

Just for the record:

I built a boost leak tester out of a piece of PVC tubing, a screw in shrader valve (tire valve), and a silicone coupler.. I pressure tested the intake system and discovered a few minor boost/vacuum leaks. After amending these leaks I ensured that my water temp sensor connector (which was crushed) was not shorting out.. A few inches of electrical tape later and I moved on to the TPS. I extended the connector with some wire leads and tested the center pin voltage with the ignition on as I rotated the throttle plate. It read from .35v to 4.2v which is almost perfect.

Then I loaded in my fouled plugs again so I could start it and look for fuel leaks and spray soapy water on all intake couplers. Started it, and it sounded alright. After reaching operational temp I took it out onto the road and immediately noticed that coming off idle was much crisper and I didnt have to rev it up and dump it just to get enough torque to move it. With first gear selected I let the clutch out..

This was my first drive in an RB powered vehicle.. This thing took off like a rocket. I have never felt such savagery. The whole car is brutally to the point and snickety in how it does things.. It's more than a little bit evil - it is satan re-incarnate....

-Dan

[Darius]

Good job! Glad you got her runnin right. Now get out of here and drive it!