vacuum leak/ car fail :(

[vkjrocker]

I have a 1988 Rx7 Turbo II just recently bought and now it just won't stay on. First thought would always be vacuum leak but it doesn't seem like it now. I've resealed gaskets, cleaned injectors and even the throttle plates. My last resorts are now the BAC valve needs cleaning or replacing, the EGR diaphram is going bad or is bad and/or a bad ground. or even the AFM maybe. maybe its the fuel pump.

I'm so frustrated now but I understand the consequences of owning a rotary.
maybe someone can throw out solutions?

[Rx-7fetish]

What exactly is it doing? wont stay on isnt much help. Will it start? Will it idle? What happens when you give it gas?

[vkjrocker]

ok so. it starts and cranks up. it won't idle when I give it gas in the beginning i feel it kicking but as soon as that happens the car stalls out.

[Red Dragon]

sounds similar to my current problem

[Rx-7fetish]

Check your air flow meter. I had one sticking on an n/a and it did the same, also check your fuel pump and filter then get back to us

[vkjrocker]

how do you check an AFM? as in does the flap open/close?
and fuel pump is working and the sock on it seems fine.

[RoughRex]

when it starts, does it run up smoothly through the RPMS and come back down before it stumbles and dies or does it start stumbling as soon as it fires? you can check the AFM with a Volt/Ohm meter, I don't have anything in front of me but I think there is are directions in the FSM.

[vkjrocker]

Originally Posted by RoughRex

when it starts, does it run up smoothly through the RPMS and come back down before it stumbles and dies or does it start stumbling as soon as it fires? you can check the AFM with a Volt/Ohm meter, I don't have anything in front of me but I think there is are directions in the FSM.

it starts and goes up smoothly and then it stumbles and dies after that :\

[12arotary]

fuel pump?

[RoughRex]

Originally Posted by vkjrocker

it starts and goes up smoothly and then it stumbles and dies after that :\

That should rule out any major system problems like fuel delivery/ spark etc I would think. It sounds to me like the trouble starts when the ECU comes out of startup and tries to adjust engine management based upon sensor readings. I would say you either have a massive vacuum or intake leak or one of your sensors is F'd. I've personally had this issue from leaking Fuel Injector grommets and when I've accidentally left a hose running to the BACV disconnected from the intake. My car is however N/A so, take that for what it's worth.

I've not tried this before so I'm not sure if it will work but, you might try disconnecting sensors one at a time and restarting the car. Theoretically the ECU should revert to the failsafe value of whatever sensor it can't get a signal from and the car will run... assuming it is indeed a sensor problem (it may not run very well though). Then again.. it may go to "limp mode" but I've not seen that personally.

Anyhow, I'm just pitching ideas at you.

[Rx-7fetish]

I wouldn't say fuel pump from that description. Check your intake piping extremely well. I missed one of the nuts holding the intake pipe to my throttle body on my n/a. Did same thing. It's because the car is getting more air into the engine than the afm is registering. It then tries to adjust fuel by what it "sees". So it's getting way more air than fuel and starving itself. Or in the case of a turbo if the leak is after the turbo then it is getting more fuel than air and flooding itself. Depends on what side of the turbo is the leaking coming from. How do your spark plugs look?

[RoughRex]

Here is the FSM section on fuel and emissions, there are direction on how to check the AFM here:

http://www.teamfc3s.org/main/factory...TEMS_TURBO.pdf

[vkjrocker]

Originally Posted by Rx-7fetish

I wouldn't say fuel pump from that description. Check your intake piping extremely well. I missed one of the nuts holding the intake pipe to my throttle body on my n/a. Did same thing. It's because the car is getting more air into the engine than the afm is registering. It then tries to adjust fuel by what it "sees". So it's getting way more air than fuel and starving itself. Or in the case of a turbo if the leak is after the turbo then it is getting more fuel than air and flooding itself. Depends on what side of the turbo is the leaking coming from. How do your spark plugs look?

sparks are fine. just cleaned them off because I believe the engine was flooded.
i've triple checked intake piping and nothing seems out of the ordinary.

[vkjrocker]

Originally Posted by RoughRex

Here is the FSM section on fuel and emissions, there are direction on how to check the AFM here:

http://www.teamfc3s.org/main/factory...TEMS_TURBO.pdf

haha yeah my buddies told me to try getting another afm and see how that worked. and yes I already got the manual from the technical page. thanks though!

hopefully I can resolve this soon :\

[Rx-7fetish]

Originally Posted by vkjrocker

sparks are fine. just cleaned them off because I believe the engine was flooded.

Crap I didn't mean clean them I meant check them and tell us how they looked it would have helped determine if your running rich or lean. And if it was flooded I would say bad afm, leaking injectors, or an intake leak between the afm and turbo. Or some combination of the 3. Try running some strong injector cleaner through your car when your down to around a quarter of a tank if you ever manage to getting it running at all. Injectors might be clogged and squirting instead of misting. It's the fumes that are combustible not the liquid.