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car revs straight to 4000 rpms then dies.

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Old 09-26-12 | 11:11 PM
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From: hamilton ohio
Exclamation car revs straight to 4000 rpms then dies.

I have an 86 rx7 non turbo i picked up for 500 bucks, with the 13b. when it starts, it immediately revs straight to 4000 rpms then stalls out. I was told the tps sensor and ive tried cleaning the maf sensor. but it still does it. what could it be?

Last edited by misterstyx69; 09-26-12 at 11:26 PM.
Old 09-26-12 | 11:28 PM
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Jump the yellow fuel pump test connector near the passenger shock tower, then try to start the car. If it starts and continues to run, the fuel cut switch in the AFM is dysfunctional.
Old 09-27-12 | 11:38 AM
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From: hamilton ohio
I will do that today and post if it works! thank you very much!
Old 09-27-12 | 12:51 PM
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From: hamilton ohio
Originally Posted by RotaryRocket88
Jump the yellow fuel pump test connector near the passenger shock tower, then try to start the car. If it starts and continues to run, the fuel cut switch in the AFM is dysfunctional.
is the wire inside the egine bay or literally behind the shock tower?
Old 09-27-12 | 01:14 PM
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Inside the engine bay. The harness it comes off runs up the shock tower.
Old 09-27-12 | 01:16 PM
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From: tulsa,ok.
It's part of the Emission Harness, which provides the wires connected to the Pressure Sensor.
The connector is usually encased in a Black rubber boot and the connector is Yellow w/a Black wire and a Brown wire.
Old 09-27-12 | 01:30 PM
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From: hamilton ohio
Originally Posted by satch
It's part of the Emission Harness, which provides the wires connected to the Pressure Sensor.
The connector is usually encased in a Black rubber boot and the connector is Yellow w/a Black wire and a Brown wire.
how would i jump the yellow wire? do u pull it out?
Old 09-27-12 | 01:34 PM
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From: tulsa,ok.
Take a short lengthed wire which you stripped off both ends to it and then use each bare end to bridge the two wire terminals in the connector plug.
Old 09-27-12 | 01:53 PM
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From: hamilton ohio
Originally Posted by satch
Take a short lengthed wire which you stripped off both ends to it and then use each bare end to bridge the two wire terminals in the connector plug.
which one the black and yellow terminals? i also have a green wire instead of a brown.
Old 09-27-12 | 01:56 PM
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From: tulsa,ok.
There are two wires you are bridging together. Since there are only two wires in the connector it should be rather obvious.
Old 09-27-12 | 01:59 PM
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From: hamilton ohio
Originally Posted by satch
There are two wires you are bridging together. Since there are only two wires in the connector it should be rather obvious.
ohhh the one coming directly form the pressure sensor?
Old 09-27-12 | 02:04 PM
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From: tulsa,ok.
https://www.rx7club.com/2nd-generati...erence-671004/

Post #3, far right pic.
Old 09-27-12 | 02:16 PM
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From: hamilton ohio
Originally Posted by satch
I jumped them and started up the car, the car is still revs by itself to 4000 and stalls out
Old 09-27-12 | 02:31 PM
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From: tulsa,ok.
Then you likely have a very large vacuum leak.
Old 09-27-12 | 02:34 PM
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From: hamilton ohio
Originally Posted by satch
Then you likely have a very large vacuum leak.
HAHAHAH i found a big hose plugged up with a spark plug in it, could that be the problem? not sure if its a vacuum line though.
Old 09-27-12 | 02:41 PM
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From: tulsa,ok.
W/o picture and so on it is not possible in any realm to know if it is or isn't. And your AFM flapper door might be stuck closed as well.
Old 09-27-12 | 02:52 PM
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From: hamilton ohio
Originally Posted by bcombs84
I jumped them and started up the car, the car is still revs by itself to 4000 and stalls out
Old 09-27-12 | 02:53 PM
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From: hamilton ohio
Originally Posted by satch
W/o picture and so on it is not possible in any realm to know if it is or isn't. And your AFM flapper door might be stuck closed as well.
https://www.rx7club.com/members/bcom...hah-wow-48580/
Old 09-27-12 | 02:53 PM
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From: hamilton ohio
Originally Posted by bcombs84
RX7Club.com - bcombs84's Album: My toys! - Picture
Old 09-27-12 | 03:20 PM
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From: tulsa,ok.
If it comes off of the back of the throttle body near the firewall and comes from the thermowax/valve then it's a coolant hose.
Old 09-28-12 | 12:04 AM
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The hose in the picture appears to be what would normally connect to the split air pipe. If the cat has been removed, it would connect to nothing. At this point, a large leak (as satch suggested) would be the most likely cause.
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