justanoob

Just got a 1986 rx7/gxl 4th gen. When Start the car the engine turns over and starts... but btween 1-5 seconds later it just dies. The owner before me said he replaced the fuel filter, fuel filter and tranny. Any ideas? Thanks alot!

Aaron Cake

iTrader: (1)

Your car is a 2nd gen, S4.

Make sure the AFM is plugged in and check the condition of the harness around that area.

Make sure there are no huge vacuum leaks in the black intake tubing between the AFM and throttle body.

RTRx7

iTrader: (2)

Does it get flooded?

Slade Gunar

i have the exact same problem. also have a 86 na- auto trans, tumbler was bad in the start position and replaced it before it would start but you had to keep the pedal at 1/6 throttle to keep it running and go under the car turn the key to start and manually jump the starter.

now when u turn the key it just chokes out when u hit the pedal.
cleaned the bac, cleaned all the ground points even the ecu and cpu. resoldered the contacts on the tumbler new one and old one, found a damaged relay and replaced it, rehooked the sub zero start valve and changed the lines, unflooded the engine. replaced the plugs and changed the vac lines and cleaned the maf before the no start happened it was working until i replaced the tumbler with a s5 tumbler had to splice into the square connector for the white plug to get it to to fit, all the wires were the same though. maybe i fried something? but my car does the same thing. its very frustrating!
i am ready to just junk it. i wanted to let you know what ive done to mine and it has the same problem and does not stay running just like this one maybe its just the 86 s4? i am willing to try about anything at this point because i want to keep mine but cant have another vehicle just sitting.... i hope this helps with diagnosing what is wrong with justanoobs. because at this stage i will try anything u guys sugest no matter how radical it may be

Slade Gunar

first thing u should really check is the fuses on the drivers side fender, does the car smell heavily of gas when it starts up and how old are the plugs?

try starting it and holding down the throttle at 1/8-1/6 throttle see if that doesnt let it keep running. check your maf that there isnt that black sludge holding the air door shut first, if its in there youll know what im talking about.

read up about the deflooding procedures also, but check if you hear the fuel going through the fuel rail it would sound like a hissing kind of sound under the throttle body. sqeeze the send and return lines by the oil filter to see if it changes the sound the rail makes.

start there and post back what your result was.

justanoob

thanks for all your input. i do not know how old the plugs are. Just bought the car off of craigslist.But yes it does smell heavy of gas when a try to start it. it even looks like a small puddle forms below and to the right of the maf. When i start the car the throttle has no affect to make it stay on longer or give the engine any power. Someone told me that I should go in the maf and take a brown wire that is in it and ground it directly to the chassy and that will signal the fuel pump to start working because he thinks it is shutting down everytime the engine starts up.

justanoob

yes it smells like it flood a little bit when i turn the engine on

Slade Gunar

how long was it sitting for before u bought it and did the person replace the fuel pump and the filter and the transmission? also is it stick or auto?

Slade Gunar

if its stick you should try and compression start it if u have a safe area to do that in... IF deflooding doesnt work.
try deflooding it first if it smells overwhelming like gas, check the plugs and clean them with a old toothbrush and carb cleaner to get all the deposits off them if you have to pull them to deflood it.
check the fuel pump before compression starting as well, theres alot of writeups on how to do it, its the next step im at for fixing mine bc ive tried everything else.....

like aaron said, check the maf and the area arround it. if you want try jumping the pump manually, that should tell you weather or not its stalling because of lack of fuel pressure without having to mess with your maf.
this rx7 stuff is all new to me... but ive been through the battlefield and back with the 924 and gremlins more times than i can count so im not ready to give up just yet on mine, well that and its the only auto i own so its either keep this or do a swap on the supra.......

Slade Gunar

i cant say going arround calling people names is going to help you get a positive response or help....

theres a few things to check. your tumbler, relays, fuel filter, try jumpering your fuel pump directly. if that doesnt work then ur in my boat =P its just old and is self aware it does not want to run anymore,
i have tried every thing. scoured for a long long time in the archives trying to figure this out and i got nothing. it just will not run. i am at awe in just how much i tried and it will not freaking run. i guess maybe swap the cpu? who knows man.
its a question everyone seems to be tired of trying to answer and no one has the answer to either. every one is so different, whats wrong wit mine is prolly whats not wrong with yours.
mine has to be related to the tumber because i changed that and thats when it no longer stayed running. since then i have tried every diagnostic step that i saw listed short of resoldering the whole computer to try and keep these maddening triangles spinning and nothing.the only thing i can come up with is that i fried something somewhere

RTRx7

iTrader: (2)

I've never heard of an o2 sensor making your car stall. Maybe a really clogged cat? Is the car flooding itself?

Slade Gunar

same as mine.
i checked the whole engine harness and fixed a few shitty wires taht were patched before, got a new battery, redid every fuse and checked every relay found 1 really rusted one under the maf idk what its for though, B092 was the number.
had it up on ramps and got it started with a ratchet between the starter terminals cause the tumbler was messed up bad when i got it due to a very old killswitch install between the st terminal. left it run for about 2 hours on ramps, set it back down, next day got the new tumbler in the mail put it in started it and it died right away been doing that ever since.
took the old tumbler and cleaned it with maf cleaner and resoldered all the contacts put that one back in, same ****. after that cleaned the bac changed the fuel filter checked the fuel pump it reads 40 psi at the filter when its jumpered, took apart the maf and scrubbed any trace of the black sludge that would be holding the air flap closed. tried multiple deflooding techniques. cleaned plugs again and again.. it still puffs a big cloud out the exhaust when it starts but when it does run doesnt smoke at all so i dont think the cat is clogged. maybe the injector seals are leaking on it.
all i know is that its really freakin cold here right now so its probably not the best time to be messing with it but its my daily driver so im desperate to get it fixed and do not want to take it to a garage because no one around here knows anything about rotarys and would probably tell me i need a new engine and compression is fine on it as well.
thats why im asking the community here because as far as im concerned people on here are experts on these cars and more reputable than any garage in my area except kdr which is a rotary specialist shop and i dont want to have it flatbedded all the way out there for something that you guys probably have fixed before and could give insight on.

AcidShock

iTrader: (49)

If you hold down the throttle does the car still die? Or does it sound like it is misfiring when you hold the throttle down? It almost sounds like you have a vacuum leak. There are one (maybe two) hoses near the throttle body attached to the intake tube. If they are not connected or leaking you will have very poor idle or failure to idle althogether. If you want to be sure, a compression test is an easy way to determine if your apex seals are shot.

RTRx7

iTrader: (2)

It could be a vacuum leak but it would have to be pretty severe. The most common solution would be to find whatever is starving the engine of air. Try removing your cat and see if that fixes it. What do you have emissions wise?

Aaron Cake

iTrader: (1)

If the car has been sitting for many years, then it is likely that one or more fuel injectors is clogged and/or locked. The only way to diagnose this is to have the injectors professionally tested.