Conquest won't start.

[Black97civic]

Alright, I am trying to figure this out before I go back to school, so I got 3 days.

For those who don't know, my car has throttle body injection, with 2 injectors. The primary is about 600cc and the secondary is about 900cc.

When I try to start the car with the primary, it idles at about 1100 rpm for about 10 seconds, then dies.

When I start it using the secondary as a primary injector, it idles at 1100rpm, smooth and steady for as long as I let it.

The voltage gauge is reading under 12 volts when it is running, and the battery light stays on, but dimmer than it is when the ignition is just in the on position with the car off. I also will add that I was using a battery charger in the "boost" position to start the car.

Could I have a problem with my charging system?? Maybe the ECU isn't getting proper voltage, so it is sending bad signals to the injectors, and the bigger size of the secondary is compensating??

What else could it be? We have checked everything and it all seems good.

[x-pride]

alternator?

[Black97civic]

alternator?

Yeah, I am wondering if that would cause the ECU to send a bad signal to the injector.

I am going to get my alternator tested on monday though, just so I can cross it off the list.

[Black97civic]

I got the alternator tested, it failed, no real surprise there. Then I got a new one, it starts up without the battery charger now, and no battery light, but it still will idle for about 10 seconds then die.

So I have:

New fuel pump/lines/filters
New Alternator
Primary Injector that I know is good

I am thinking maybe a leaking injector is flooding it out, so I am gonna try and get my friends other good injector to try and see if that fixes it.

[Kougar]

Wait, huh?

Leaky injector makes sense, but if the primary is good...how would it leak? The secondary doesn't come on until the demand for fuel is increased, right?

Does the car rev normal within the 10 working seconds? Or JUST idle? After the thing dies, try taking off the EGR (hopefully you have an EGR blockoff, making it easier) and see if fuel leaks out.

The FPR is good, right? Perhaps that has a leak? Have you pulled the vacuum hose off it to see if fuel drips past?

[Black97civic]

Leaky injector makes sense, but if the primary is good...how would it leak? The secondary doesn't come on until the demand for fuel is increased, right?

It still gets pressure, so if seals are bad it would get passed them and drip out.

Does the car rev normal within the 10 working seconds? Or JUST idle? After the thing dies, try taking off the EGR (hopefully you have an EGR blockoff, making it easier) and see if fuel leaks out.

Haven't tried to rev it yet, will report back in a little bit.

The FPR is good, right? Perhaps that has a leak? Have you pulled the vacuum hose off it to see if fuel drips past?

FPR doesn't leak fuel, and holds good 38-40 psi at idle.

[Black97civic]

It was a bad mass air flow sensor.

When we started unplugging things to see if we could eliminate broekn electronic components, we got the mass air sensor, unplugged it, and got a perfect 1000 rpm idle, soon to be adjusted to stock spec.

I think this might say something about the ECU. My best educated guess is that the ECU doesn't get any information, or doesn't use it at least, from the sensors for about 10 seconds, then it starts using signals to run the motor.

Thanks for all the help guys!! 2 more months and there will be 1 more conquest on the road!!

[Kougar]

Glad to hear you found the problem!