vacuum leak/ car fail :(

vkjrocker · 01-19-2010, 11:13 AM

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 · 01-19-2010, 02:58 PM

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 · 01-19-2010, 03:13 PM

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 · 01-19-2010, 04:05 PM

sounds similar to my current problem

Rx-7fetish · 01-19-2010, 09:31 PM

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 · 01-19-2010, 10:26 PM

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 · 01-19-2010, 10:48 PM

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 · 01-19-2010, 10:59 PM

Quote:

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 :\

RoughRex · 01-20-2010, 06:03 PM

Quote:

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 · 01-20-2010, 07:08 PM

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?

vkjrocker · 01-21-2010, 03:14 AM

Quote:

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.

12arotary · 01-20-2010, 04:09 PM

fuel pump?

RoughRex · 01-20-2010, 08:30 PM

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 · 01-21-2010, 03:18 AM

Quote:

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 :\

01-19-2010, 11:13 AM	#1
vkjrocker Rotary Fan in Training Join Date: Jan 2010 iTrader: (0) Posts: 32 Rep Power: 0	vacuum leak/ car fail :( 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?

01-19-2010, 04:05 PM	#4
Red Dragon Rotary Enthusiast Join Date: Apr 2008 Location: Birmingham, AL iTrader: (0) Posts: 129 Rep Power: 17	sounds similar to my current problem __________________ N/A 1987 RX7 (restoration coming along)

01-19-2010, 10:48 PM	#7
RoughRex Out of Nickels and Dimes Join Date: Mar 2008 Location: Nashville, TN iTrader: (0) Posts: 192 Rep Power: 17	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. __________________ 1988 GXL

01-20-2010, 07:08 PM	#10
Rx-7fetish Blue Blur Join Date: Jan 2009 Location: Windsor iTrader: (0) Posts: 211 Rep Power: 0	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? Last edited by Rx-7fetish; 01-20-2010 at 07:10 PM..

01-20-2010, 04:09 PM	#12
12arotary tumor-syphilis-itis-osis Join Date: Sep 2008 iTrader: (0) Posts: 191 Rep Power: 17	fuel pump? __________________ 82 300d 82 Gsl 84 b2200 Diesel 88 gxl

01-19-2010, 02:58 PM	#2
Rx-7fetish Blue Blur Join Date: Jan 2009 Location: Windsor iTrader: (0) Posts: 211 Rep Power: 0	What exactly is it doing? wont stay on isnt much help. Will it start? Will it idle? What happens when you give it gas?

01-19-2010, 03:13 PM	#3
vkjrocker Rotary Fan in Training Join Date: Jan 2010 iTrader: (0) Posts: 32 Rep Power: 0	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.

01-19-2010, 09:31 PM	#5
Rx-7fetish Blue Blur Join Date: Jan 2009 Location: Windsor iTrader: (0) Posts: 211 Rep Power: 0	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

01-19-2010, 10:26 PM	#6
vkjrocker Rotary Fan in Training Join Date: Jan 2010 iTrader: (0) Posts: 32 Rep Power: 0	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.

01-20-2010, 08:30 PM	#13
RoughRex Out of Nickels and Dimes Join Date: Mar 2008 Location: Nashville, TN iTrader: (0) Posts: 192 Rep Power: 17	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 __________________ 1988 GXL