flipsidefabrication

Guy put an adjustable fuel regulator on my truck. He had it set so low it kept falling on its face. I turned it up to 42 and it seemed to run fine. Drove it around a bit. Kept taking longer to start. Then on the way home died on the highway. I think i had it turned up too much and flooded it. If anyone knows exactly the amount of fuel pressure a stock 3.0L takes it would help me out a lot.

Thanks

4banginRunner

38-44

flipsidefabrication

hmm i wonder why it just flooded out then

scope103

How do you "know" you're getting 42psi? Because there's a number on some box installed by "Guy"? For that matter, why do you think you flooded it?

You can end up chasing your tail for a long time until you actually know what's going on. Since your truck has already been "modified," you really need to get a fuel pressure gauge to see what it's trying to do.

You could also look at the stored fuel trim; if you're really running 42 psi then the ECM has to compensate by dropping the fuel trim. Only once you run out of range the engine could flood (but you should get a code long before that).

Punchy

I set up and fuel pressure gauge on mine and I can tell the fuel pump is aftermarket, I get from 37-50psi and runs fine.

35-45 is normal and the engine will work fully if its stuck at 35, The ECU will learn to compinsate the difference.

abecedarian

Fuel pressure should vary between 38 to 44 depending on what the engine's doing / how you're driving.

With low manifold vacuum, the fuel pressure should be close to 44, and with the throttle closed should be 38. Fuel pressure should be somewhere in between and is related to manifold vacuum.

Small changes in fuel pressure can significantly affect the fuel mixture and overall driveability of the vehicle.

The ECU can compensate for it somewhat, it can only do so while the ECU is sampling the O2 sensor. It only does so when the throttle is not closed (i.e. at idle no O2 feedback) and cruising at a relatively constant speed (i.e. no significant or sudden changes in throttle position). So high fuel pressure can flood the engine at idle, and low fuel pressure can cause the engine to run lean at wide-open throttle; that's why the fuel pressure varies.