Ok, I have a 1988 TII that is bone stock and from time to time it won't start. Here is what happens. I work downtown about 15 miles from home, and the roads down there are notorious for being rough as hell. When I come out in the morning to get my car from the garage, sometimes it will not start. There is no tach signal which means that I am getting no spark for some reason. I have a fuel pressure gauge on it and it is normal while this is going on. Also, I have had it towed several times and it always starts right after it gets towed. We changed the main relay the last time this happened and it started right up. This morning the same thing happened again and after a tow truck trip to my dads it started up fine.

Fuel Pump is out of the question-good fuel press.
Main relay is out of the question-just changed over


So, guys what can it be? It starts up fine now and it is very difficult to get it to act up when I need it to!

 

It sounds like you're experiencing typical flooding.

I would first do a compression check to verify the integrity of the engine as its a major factor of flooding. Ideally you should have at/near or above 100psi per face, per rotor. At, near or under 80 and you have problem.

After that, you have a couple of options. If the compression is decent (say 90psi) then I would attempt a bandaid fix for the time being. I would install a fuel shut off switch (just install it in-line right at the fuel pump's power wire, or at the relay under the dash) and utilize it by having the switch OFF during cranking, then after a few seconds turn it on to allow fuel to pump. The idea being to minimalize fuel entering the engine during cranking.

If it gets worse you can go as far as using the switch to actually shut off the car, which will mean you won't have any excess fuel in the engine while it sits. Then to start it crank it over, andthen turn the switch on.

If its severly flooded you'll need to do a de-flood, and a quick search will pull up the lenghty procedure.

Ideally, if the compression is low (at, near or under 80psi per face, per rotor) the REAL fix is a rebuild. But this should get you by for the time being.

 

^^^agreed.

 

The engine is not getting a tach signal during startup when it wont start, which says to me that there is no way it is flooding. Also, I have had a few rx7s and experienced flooding quite a bit, this is not what is happening. I guess the key thing here is it pretty much only happens after driven downtown where the roads are rough and full of potholes. I havent driven it downtown in over a week now and it hasnt done it yet.

 

Fix is!

Evade that road.
:p

 

check all the wires on your wire harness, mostly the wire that leads to the starter. if it doesnt start wiggle the wire harness and then try to start it, before you know it you will have the wire thats causing the problem and then fix it, i d the same problem.