I have a race this weekend but my RX-8 always dies 4 seconds after starting. Help?
#1
I have a race this weekend but my RX-8 always dies 4 seconds after starting. Help?
So... I just installed a fresh motor in my RX-8 race car. It's a 100% stock motor using the stock ECU etc. (It does have a header, racing beat flash, light flywheel, AEM intake, no cats or smog equipment)
The motor will start and seems to run ok but after about 3-5 seconds it always dies - even if I bring the revs up with the gas pedal.
My first though was an air leak somewhere and guess what! I did have one (left the brake booster hose off - duh!). But this did not fix it.
Then I thought maybe I connected the fuel injection wiring harness wrong. So I got our a wiring diagram and guess what, I had two of the injector plugs swapped incorrectly. I fixed this and it ran better but STILL always died after 3-5 seconds of running.
I've tried deflooding, changing spark plugs etc.
Is this perhaps the fuel pump? Someone told me that the fuel pump has a mode where it is activated when you crank the motor but it's possible for it then to turn off after you stop cranking. If this is the case how do I trouble shoot this?
Any ideas?
The motor will start and seems to run ok but after about 3-5 seconds it always dies - even if I bring the revs up with the gas pedal.
My first though was an air leak somewhere and guess what! I did have one (left the brake booster hose off - duh!). But this did not fix it.
Then I thought maybe I connected the fuel injection wiring harness wrong. So I got our a wiring diagram and guess what, I had two of the injector plugs swapped incorrectly. I fixed this and it ran better but STILL always died after 3-5 seconds of running.
I've tried deflooding, changing spark plugs etc.
Is this perhaps the fuel pump? Someone told me that the fuel pump has a mode where it is activated when you crank the motor but it's possible for it then to turn off after you stop cranking. If this is the case how do I trouble shoot this?
Any ideas?
#6
I figured it out. I'm a moron. When I replaced the engine this time I also eliminated the air pump. Turns out the air pump has a resister attached to it that it part of the fuel pump electrical system. As I had thrown away the air pump I just jumped the connector in the wiring harness and that was good enough to get the car running... didn't want idle when hot but otherwise was fine.
#7
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I figured it out. I'm a moron. When I replaced the engine this time I also eliminated the air pump. Turns out the air pump has a resister attached to it that it part of the fuel pump electrical system. As I had thrown away the air pump I just jumped the connector in the wiring harness and that was good enough to get the car running... didn't want idle when hot but otherwise was fine.
![Lol](https://www.rx8club.com/images/smilies/lol.gif)
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