i have a 88 t2 rx7 s4 and it has a hard starting problem. For some reason it needs to build oil pressure in order to start so i have to crank it like twice in the morning but in the afternoon when its hot it struggles to start sometimes stall. I thought it was the fuel pump relay but i checked it, it seemed to be working. Could it be that the fuel pump relay is only semi working?

 

The 86-88 cars (S4) are notorious for hot/flooded start problems. This sounds like it might be your problem, since you report more difficulty in the afternoon when it is hot.

Next time it has trouble starting, try this: Stop trying, open the hood, find the EGI fuse (main fuse block just at the front of the right wheel well). Pull out the EGI fuse. Get back in, crank it for 20 seconds or so (it wont start, no fuel). This should clear the flooding. Stop cranking, get out and replace the fuse. Then try starting it again. If your problem was a flooded/hot start, it will start right up.

 

i dont think flooding is the problem. I always leave my car running 5 mins before i shut it off. When its warm it stalls sometimes when i start it up. I have to hold the throttle for a min for something to build up im guessing the oil pressure so it wont stall and after that its fine. I did all the major tuneups for the car fuel filter, oil, spark, wires. I dont know what can cause it to stall on startup.

 

Looking at my Haynes manual it suggest checking the hot start assist system. It is too complicated to state here but it has you check the resistance of the temperature sensor which is located between the intercooler and the throttle body with the engine warm. There are also numerous other checks in the troubleshooting section. I guess I am suggesting you buy a Haynes manual to really fix your problem. Good luck.

 

I'm guessing you would have added it to your intro for this tread but I was wondering if it smokes when you start it. My 88 gave me the same problem never stalled but it would hesitate if I tried to leave with out warming up, I would have to apply more gas to compensate, it got to where it was back firing. I did the ATF trick and replaced the spark plugs and its doing a lot better now.

 

It's not related to oil pressure.

Sounds like the typical flooding/hot start issue.

Make sure the car is in good tune, adjust the TPS, have the injectors serviced, check compression.

Don't bother with things like ATF. It won't help. Replacing the spark plugs is what works.

 

it does smoke when i start it up in the morning im thinking thats because of my leftover seafoam it goes away after like first 5 seconds. I changed the plugs, wires, fuel filter, oil. I adjusted the tps. But after i removed the tps and started the car it started fine but it just wouldnt accelerate. So im thinking it could be the o2 sensor so ima get that replaced. Compression was tested at 95 psi on both rotors