Gomer_Pyle

I know this site is plagued with people having starting problems. Im having one again, at first it was the fact my starter wore out which in turn caused it to flood. I got it rebuilt and tossed it back in. Cranked it over wouldn't start did the ATF trick and I fired right up. I let it get to operating temp and drove her around the block w/o any problems. I get back home kill it and tried to start it back up, which it did. An hour later i jumped back in and she wouldnt start again cranked over great, started once and died almost instantly. I figured i try the ATF thing again for the hell of it well it worked. I killed it and she wouldn't start.

Ok the things im thinking that could cause this are low compression w/bad APEX seals. Or maybe something to do with the oil injection not operating correctly.

Cars Stats
87 RX-7
13B
74,000 Miles

Do either of my ideas play out? I know the low compression makes since the oil filling the void between the seal and the wall till the metal expands. But the oil injection thing kinda has my attention to maybe its not injecting oil at start up allowing a gap between the seals to the wall. Thus causing low compression. When i crank it over you can hear it try to start and puff out smoke from the ATF.Telling me its firing.

Thanks for any input
Andy

toplessFC3Sman

iTrader: (1)

starting problems are always better than stopping problems...

my guess would be low compression, or a very leaky injector that could keep flooding it possibly. The oil injectors not working wouldnt directly keep it from starting, they would just make the apex seals wear a lot faster than otherwise, however this could be causing your starting problem since worn apex seals = lower compression.

freemanrx7

I would say leaky fuel injector! Try to get the car started again. let it idle for 20 min or so. Turn OFF. Try to start an 1/2 an hour later. If it fires up then it might be the secondery injectors leaking. The sec injs come on at higher rpm. Thus it wouldn't drip any gas after just idleing.

When extra gas is leaked into the rotor housing the gas causes the seals to curl thus leaving no compression for it to start the next time.

THIS IS MY BEST GUESS!! ANYBODY ELSE?

toplessFC3Sman

iTrader: (1)

no, the test you described wont rule out or identify the secondary injectors. by starting the car you'll re-pressurize the fuel rail, and if any of the injectors was leaking, it would continue to leak after the car was shut off until the rail no longer had any pressure in it. A better test of this would be to start the car, drive it, let it warm up w/e, and then disconnect the fuel pump and let it die. This way there wont be any pressure left in the rails to leak past. Then in a half-hour or hour or so re-connect the fuel pump, and try to start it. If it starts right up, you're in luck, its a leaky injector. Just wire up a fuel cut switch to somewhere you can easily access it (and if its hidden, its a theft deterant too!), and shut off the car by killing the fuel pump.

freemanrx7

I think I've seen a few writeups on a custom fuelpump shut off switch. This seems to be a common problem on older 7's.

toplessFC3Sman

iTrader: (1)

yea, the easiest way is to just wire a switch inline with one of the signal wires from the fuel pump relay (which is located under the dash close to the driver footwell IIRC). If you dont want to go digging thru your dashboard tho, you can always just trace the wires back from the fuel pump and put a switch in one of those. One pair is for the gas gauge and the other pair is for the pump power. I dont remember the wire colors off the top of my head, but the FSM is sure to help you out.