S13 SR20 Overheating

[s14brennen]

I just finished swapping in my s13 blacktop and it overheats after about 5 min of driving or even 10 min of idling. I bought a new thermostat and swapped that in but it didnt seem to help. It seems like the coolant isnt circulating through the block so it might be the water pump but is there anything else? Any help is appreciated, thanks alot.

[supreamS14]

You can over heat by constricting flow or loosing pressure. Thought about trying a flush?Do you go to bradington motor sports park or desoto speedway?

[s14brennen]

I've gone a couple of times to watch but not recently.

[jeking1]

my guess is you swapped an s13 sr into an s14 body? make sure you switch the temp sensor to an s14. You can get it off a ka motor, they are interchangeable. You should just go ahead and change over both sensors. the s14 gauge cluster reads a different signal than the s13. the one that reads to the gauge is the single wire one.

[s14brennen]

Thats exactly what i did. S13 Blacktop into my 96. I changed out the gauge sensor today and it reads much better, the temp i thought was overheating turned out to be normal after changing the sensors. Now the thermostat is kickin in and allowing coolant to flow through the motor. Idk if this has anything to do with that second sensor but now i have a crappy idle once it gets up to running temp. The startup rpm is around 900 then once warmed up it will drop to almost nothing then shoot back up to 1200 or so then back down to less than 100 and keep repeating. Any suggestions? Will that other sensor fix this?

[el OCHO]

timing???

[Silvia007]

You shouldn't have to swap it out. It's sending the right signal to the ECU. Is it hooked up? If it's bad or not hooked up, you'll experience hard startup or no startup at all even when engine cranks when it's warmed up.

[nissanracer300zx]

What you should do is fill the radiator with water and coolant and then remove the coolant temperature unit so you will see that water and coolant is coming out from the temperature sending unit hole that way the car wont overheat.

[jeking1]

did you change out the second one also? if so, go back to the old one, the only one you really need to rely on is the single wire one for your gauge. if you changed the 2 wire one and it started running bad, then that sensor is most likely going out, try another 2 wire sensor. keep your single wire tho, that will keep your gauge reading correctly.

[s14brennen]

I only changed the single wire so far but im going to change the double wire one today to see if it helps with the idling. Fingers crossed.

[jeking1]

you shouldn't have to change out the two wire one, the one that came with the sr is the correct one to read with that ecu. Could be a different prob all together. I would definitely check the cas (cam angle sensor) to see if it is lined up correctly.

[s14brennen]

yea i was thinking it made no sense to change out the 2 wire sensor since the one thats in the sr is right for its ecu. but as of now it still idles terribly once it gets to running temp. Now its starting to stall sometimes and other times it will bounce off of 100 rpms up to 1500rpms and come to a stop around 700rpms. and as far as the cas, what do i look for when its out? i dont want to take it out and screw it all up.
Modified by s14brennen at 9:06 PM 7/22/2008

[s14brennen]

Just figured it out. When i did my swap i threw on a new Greddy Type RS bov and all i did was tighten the adjustment screw and it fixed the idle perfectly. I guess the bov spring was loose and allowing air to excape which the computer wasnt picking up on. So a tighten of the screw and all is good. Thanks everyone for your help.