The coolant temperature sensor and oil pressure sending unit are near each other on the driver's side of the engine block, below the oil filter pedestal.

(I found these images on either RX7Club or Google.) - The circled item is the oil pressure sending unit. To the left of the oil pressure sending unit is the coolant temperature sensor. It's a little prong that sticks out. It isn't really visible in this picture.


This is what connects to the oil pressure sending unit.


There is a yellow wire with slightly visible red stripes that is on the coolant temperature prong. That connector in the picture doesn't have the plastic connector piece on it... It is actually a "bullet" type connector that it uses. (Note: You can also see how the oil pressure wire connects to the oil pressure sending unit in this picture.)

 

AHH! i was wondering what that little yellow wire was for! Thankyou soo much! I'll plug that in tomorrow and tell you how it goes. (:

 

Okay, so i got that coolant temp sensor in. Thats all workin good. But im still a little unsure of the oil pressure gauge. I found the little yellow wire with the yellow tracer and the square plug, and i also found another. They were just hanging there hidden behind other wires. I'll get a picture of it tomorrow.

Besides that, I finally got to drive it today. It was awesome, but i was terrified of oil pressure, so i didn't go far or fast.

 

A malfunctioning oil pressure gauge is pretty common.

Either the connector terminal is dirty, the sendng unit needs to be replaced, or the gauge is fried.

 

Alright. the oill pressure stuff is all perfect. the clip is just broken i think. everytime i start my car it falls off. any easy fix for this?

also, my reverse lights don't turn on when i'm in reverse. is it just a plug on my trans?

aaand, when pulling in boost my car struggles to make it over 5500rpm. Perhaps the pressure sensor is getting a bad signal? or maybe the fuel pumps can't keep up? any ideas?

 

Okay, more questions.

My oil pressure sensor clip doesn't stay on. can i replace it with an ordinary female spade clip?

also, what is average oil pressure for an 87 turbo 2? and should my n/a gauge cluster read as it should?

 

The reverse switch is on the transmission. If the transmission is NA or US-TII, it will have 4 prongs. 2 are for the rev. switch, and 2 are for the other side (5th gear switch). The wiring for the transmission switches is on the engine harness (same one as the starter). Compare wire color to what's listed in the FSM wiring diagrams (see 2nd gen FAQ).

How much boost pressure is it making, and will it make it to redline at partial throttle? If boost is dropping off, what pressure are you seeing by 6-7k?

What fuel pump? Stock? What injectors? Stock 550cc?

No. You'll need the special slide-on connector for that T-shaped post. I have no idea where to get one, but you could try radioshack or an electronics supplier like Mouser Electronics.

25-30 psi at idle, and 60+ psi above 3k RPM. Oil pressure gauges are the same NA or TII. The gauges/senders are more of "guidelines" after 25 years of service. If you really want to know oil pressure, a mechanical gauge is more trustworthy.

 

Okay, at idle mines around 60. could this be caused by all emission controls disabled on my car?

 

Emissions have nothing to do with oil pressure. Either the sender is giving you a crazy value, or someone may have messed with the oil pressure regulator(s) on the engine.

 

well is there any easy way to tell if its been messed with? anything i should look for?

 

More questions!

So i'm not sure if this is factory or not, but theres a little red switch on the driverside that turns off my tail lights, and licence plate lights. it looks like the previous owner put it in.

Now if he did i think he messed other lights up because my dash lights don't work. i can't read anything gauge wise (in the dark). I checked all the bulbs and those are just fine. the dimmer doesn't do anything for me either. Any thoughts on that would be greatly appreciated. (:

 

No, there's not supposed to be a switch to turn off the tail lights and license plate lights. That sounds like some sort of "running from the cops" switch.

Check fuses with a multimeter. Typically the problem you mentioned with the gauges is just the dimmer turned all the way down, but it could also a switch problem.

 

So more questions. My car pulls real hard but studders after about 5500 rpms. feels almost like a designed limiter. Could this be the boost sensor freaking out? fuel issues? injector issues? Any help would be greatly appriciated.