Brice's NA V6 Build

If for some reason the pump was increasing the fuel pressure, somehow, then I could see how it would be running extra rich. Not without increased fuel pressure will the pump supply past what the injectors are commanded.

Should the fuel FPR be hanging up due to boost reference, and damaged its tiny diaphragm, then I could see that causing a rich condition. Happened with my old FPR, all off a sudden, it just stayed rich all of the time. Stock ecu running things. Wouldn't even accept lowering the pressure. The diaphragm had just stuck somehow.

Is it idling normal now? Or smell really rich still?

 

Idles ok but liquid gas comes out of the tail pipe. I may look at the fpr again... If it is bad I'd like to replace it with a aftermarket one.

 

He switched to a Bosch I think, the same one used in 2jz engine and noted how much larger and beefier the unit was despite being rated at the same flow rate. I don't think AEM are great pumps.

 

Figure out the AFR sensor/gauge, first.

You say it idles ok. Does that mean that it idles better than before with the AEM running the show?

If you give it throttle, does it bog or seem to have a rough time, increasing in RPM's?

Pull the spark plugs on the passenger side and see how they look. Any time your engine runs in the 8's AFR's for a length of time, it has a high potential to get cylinder wash.

Were that the case, you'd pull the fuel pump relay, and prime the engine a bit, to get oil circulated.

If it ran at 8's for too long, you could have fuel in your oil pan as well.

 

It idles ok with the fic 6 and without it, but that makes sense since the fic6 doesn't do much at idle accept subtract fueling. (which it cant do at the moment because of the rich issue)
It revs ok when I give it throttle at idle.

Im calling AEM today to see what they say about the wideband situation, hopefully they know something I don't.

Also I'm assuming the 2jzgte fuel regulator bolts to the 5vzfe fuel rail?

 

I'm not sure if he changed his fpr, I was referring to the pump. I think the stock fpr is good but don't quote me on that.

I agree with Tor about the fpr but IIRC Josh had the exact same issue and it turned out his fuel pump was bad.

 

I'd have to look, but I think he had a Walbro originally. Let me go look.

 

How does it drive now, with the oem ecu and injectors?

If it drives fine, then it is the AEM.

If it drives fine, then this scenario seems similar to when my Map-Ecu2 failed, and had just started dumping fuel no matter what adjustments, positive or negative, were made.

 

So what is the fix?

 

Getting a fuel pressure tester thing sometime this week, but other than that it's still a mystery. I think like clay said originally, it's the fuel pump.

 

Be very odd if it is, but you can't rule it out.

Maybe something is blocking your return line??? Who knows yet. Curious to see the outcome.

This is why it is very important to have at very least an adapter for a fuel pressure gauge.

 

A in cab fuel pressure gauge is on my list now... well assuming my fuel pressure is wonky

 

There or even one in the engine bay, as well.

 

What are your symptoms again?

 

Is it a returnless fuel system?

My thought, is maybe the pump is set to constant flow, rather than a PWM flow.. Kinda basing this off of the idea that the stock, lower flow injectors allowed the truck to run, but still too rich.

 

No it's a return system

 

Runs 8:1 at idle and backfires when driving on 650cc injectors. I haven't driven on the stock ecu and injectors yet to see what happens then.

 

You should. Just around your house.

 

Nothings wrong with your fuel pump or regulator. That's just running way rich. You need to tune the injector pulse width before you even try to tune the engine.