2000 Astro - flood on cold start

[hi-tech]

Hi Guys. I am a former Chevy Master Tech, but that was a decade ago. I got out just as OBDII was coming in. I have a 2000 Astro that floods at the drop of a hat on a cold start. Don't have access to a scanner, don't know if it set codes, can't read the CTS to see if it is open or not. I am not familiar with the injection system on this one, don't know if this is a common issue, or maybe a MAP sensor, causing full fuel flow. Primary and secondary ignition are all good. Just looking for a little direction on troubleshooting this without a scanner - i.e. common problem like this with this model.

Any help would be appreciated. In return, I will be watching the forum for anything I can help with on the older cars - my era!

Thanks!

[MT-2500]

A computer read out would help.
Any check engine lights?
But they are also sensitive on the fuel pressure.
Is it a 4.3 v6?
Here is some guide lines on fuel pressure test.
Hard to start cold.
Check cold start fuel pressure.
Check engine running fuel pressure.
Check engine running on the road fuel pressure.
Then shut it off and watch for fast leak down.
Pinch off at rubber part or block off return line and check full pressure.
Later V6 and V8 gm engines should have 60-66 fuel pressure.
Cold start should be 64-65 lbs of pressure.
If you do not have full fuel pressure on a cold start the injectors will not squirt fuel.
Do not leave home without it.
Engine running should be 60-66 lbs pressure depending on engine load.
Full pressure with return pinched off should be 75-85 or more.
And if it has a fast leak down after shut off you have a leak.
Post back fuel pressure readings.

[hi-tech]

Yes, fuel pressure is good. The problem seems to be a massive dump of fuel happening. If it starts right away, I mean RIGHT away, it's OK, but if she spins a couple of times, no start and strong fuel smell outside the vehicle. Seems to be similar to the CTS issues we had years ago, where the sensor goes open and the ECM interprets -40F and dumps massive amounts of fuel. But I don't have a scanner so I cannot watch the CTS readings. I was hoping that someone could tell me a common issue that sounds like this.

[MT-2500]

It has two tempt sensors besides the tempt gauge sensor one eng to pcm and the other one is the air intake sensor. Make sure the air intake sensor is not unpluged. When the air filter intake hose is removed a lot of times it gets left unpluged.
Look under air intake hose at tbi for air intake sensor.
Also look your vacume lines and other sensor plugins over.
Outside of that you need to borrow or rent a scanner and read out sensor readings in the computer.
Good luck MT

[hi-tech]

Heres the latest. The vehicle has been sitting untouched for the last few hours, I put a charger on it to bring the battery back up. Would not start earlier today. Trying to apply some logic, so I keyed it up, waited a second or two for the TPS to register at zero, then to the floor to go into clear floor mode. The thing started in a heartbeat and runs like a top. Coughed out some smoke from being flooded, but runs great. I let it get up to 180 and shut her down til the morning. See what happens then. Tomorrow I will begin systematically checking vac lines and sensor connectors.

Thanks MT. (Master Tech?)

[hi-tech]

Popped right off this morning, not even a though of flooding. The outside temp at 8:00am was around +20F. I am just not sure what to make of it. I really though it was temp related. Possibly not.

[MT-2500]

I would get a fuel pressure gauge on it and tape it to the windshield or mirrow and watch that fuel pressure. Make sure it is in specs at all times cold start engine running on the road and at idle and watch for a fast leak down.
Pressure leak down indicates a leak someplace and if the pressure is off even 3-4 lbs it can give you problems.
Post back your pressure readings as I outlined in the hard start test.
MT

[jackastro]

Hey high-tech, I have a 94 astro with somewhat of the same problem. Haven't figured it out yet either. At start up if it doesn't fire right away I hold the pedal to the floor and then it starts right up. Van runs great from there. Don't have any fuel smells but a rich smelling exhaust. Go to the "95 astro runs rough" thread and scroll down till you see 94 astro with my screen name "Jackastro" to read more about my dilema.