1987 supra na will not start after running for a while.

[raquetman]

All,

I have a 1987 Supra NA.

My problem is that when I drive the car for a few minutes, it will not turn over or start. The car does not get hot and there are no warning light coming on in the dash.

After cooling down for 5 or 6 hours, or overnight, the car will start.

Any Ideas what the problem may be?

Help please.

[mrnickleye]

If it does not 'turn over' (crank the engine), then it is in the starting circuit.

battery
battery terminals
starter connections
Starter
starter relay
ignition switch

http://www.cygnusx1.net/Supra/Librar....aspx?S=ST&P=1

if its the starter, forget about all that testing and rebuild section, just get a reman from parts store.

[raquetman]

I have replaced the battery and starter. With the same results.

I was reading up on this on the web, and I think it might be the neutral switch for the auto tanny.

Do you think this could cause it?
If so, how can the neutral switch be adjusted or tested?

[oowee623]

i had a problem with the nuetral safety switch too until i got it bypassed

[raquetman]

Originally Posted by oowee623

i had a problem with the nuetral safety switch too until i got it bypassed

Can someone share the instructions for "BYPASSING THE NUETRAL SAFETY SWITCH?"

Thanks

[oowee623]

well theres 2 ways to do it, one way is to find the 3 wire plug coming from the tranny, the wires should be black, white and i think the third is blue, cut the black and white wire and splice them together to bypass the neutral safety switch, this method is used in an auto to manual swap but it should work for autos too.

the second way i learned from my dad. what you need for this one is some electrical wires and a push start button from radioshack or electronics store(optional but recommended), splice some of the electrical wire to the starter harness i thinks its brown and connect another peice of wire to the postitive battery terminal and run both through the firewall, since your car is automatic you can run it through the precut hole where the clutch master cylinder should be, careful not to touch the wires together while doing this or youll crank the engine or cause a short. run the wires to the coin slot and take the coin slot and cut a hole in it for the push start button. then crimp some small terminals to the wires and connect it to the button and you have yourself a push start button/neutral safety switch bypass but the key has to be in the on position to start otherwise it will just crank the engine, the button is optional cause you can just jump the two wires to start the car

i suggest you try to adjust your neutral safety switch first and if it doesnt work go ahead and try to bypass it. but be careful with it, the neutral safety switch is a safety feature, bypassing it allows you to start the car in any gear, and your wiring should be clean and not half-assed or sloppy or it will cause a short

[raquetman]

Thank you!

I appreciate everyone's thoughtful comments here.
I will try your suggestions an let you know how this works out.

[supraman121]

I had it similar problem, it was the alarm. you could maybe have that checked out.

[btwilson86]

As for bypassing the switch, when I got mine the previous owner had done it already with the first method (splice the wires together). This does work efficiently, as it starts everytime in every gear. However, I kept getting the CEL for Neutral Safety Switch/AC Compressor. So I just went to Pick A Part yesterday to pick up a used switch, and I'm gonna hook it up and hope it fixes it (The contacts on the switch that came with my car were worn out, causeing it to only start sometimes). Hope this helps.

[mrnickleye]

If the N/S switch is just out of adjustment, (and not bad), you should be able to hold the key in the start position and move the shift lever back and forth from reverse to drive.
Across the neutral position, and the starter should work.

The alarm thing may be your problem. Can you put the key in the 'on' position, and then, using a starter jump botton (buy one),jump the starter and start the car.

Read:

http://www.toyota-supra.info/forums/...ead.php?t=9087