Thanks a lot Kyle! I will try this tomorrow It's 1 at night here in norway, so sadly I must wait hehe

 

BAH! Some of my most productive work time happens between 1AM and 6AM! Well, now that I have insulated my garage so I don't wake up the kids/wife when I'm welding/grinding/banging away!

 

Then the plenum is back together for now. And I have made some small changes hoping they will work as a temp fix.

I belive that the leak was/is coming from one or two of the fuel lines where they are connected to the CPI with some O-rings and a metal clip. On the driver side where I have no washing the area around is dirty. On the passenger side the fuel lines and metal clip is almost spot free.
Sure it could be the FPR, but with key on several times, there's no leak coming frem the FPR.

I pulled all the fuel lines on the passenger side and changed the O-rings.
Right away it gave me a more stabil idle, cleaner running and I think the sulfur smell is gone from the exhaust. It will take some more test driving, but for now it's good.

I will order a new CPI but I need the car as a daily driver, so I hope it works for a little time.

Pictures:

Driverside:



Passenger side:


I played around with this metal clip and fuel lines, so most of the dirt you see in those two pics are from my hands.....
It was much cleaner before I played with it....

This fits with the washing in the plenum......

 

Don't forget the 'nut kit'. Should be replaced when it gets removed after extended service. Those things like to leak if they are moved too much.

 

Yes, I also put a "nut Kit" in the shopping Cart.....These things (CPI) ain't cheap!

 

While I'm waiting for my new CPI and nut kit I'm doing some more research and I'm not convinced. I can't find the leak. I have once more done all kinds of tests. Vacuum, fuelpressure, visual inspection, monitored the fuel trims etc. with OBDII tools. I'm working on a new video, that will cover all this, maybe that will give some clues. My Long trim fuel trim stopped at 7.80%, is that to high?

I'm sure there is a fuel leak somewhere, but I would like to know for sure, not only swap out parts and leave it at that.
The best clue that I have a fuel leak, my oil was filled with fuel.
I'm had a oil leak at the cooler lines for some time, and now and then I have added oil to the engine keeping it topped up.
I still has this oil leak, but NOW my oil level rises.
Changed the oil today as a precaution until my CPI arrives, and the oil was super thin, low on lubrication, and SMELLED like the inside of a gass tank.

By the picture I provide some posts ago, there is NO doubt that there is a fuel leak present, don't you think?
Are there something like a intermittent fuel leak inside the plenum?

 

From the sounds of it, you definitely have a leak inside the plenum. There is no other way for fuel to find its way into the oil. Was that a positive or negative LTFT?

 

Glad to see that you dropped in Kyle!

Long Term Fuel Trim, positiv 7.80
Short Term Fuel Trim fluctuate some between -3.90 to 3.12

 

Your PCM is richening up the mixture. This could possibly be in response to a lower than normal fuel pressure..

 

How do this fit in with the fuel leak? It can't be that clean on the passenger side and so dirty on the driver side, without there being a leak on the passenger side.

My active fuel pressure is good, at the fuel pressure test port.
62psi key on, 55-58psi running. It's the leak down test that has sign of a fuel leak. Goes from 60psi key off, down to 15psi in only 20 minutes.
This is worse now then it was before I started playing with the CPI unit.
And it will still hold pressure longer with a cold engine....

But it's a new acdelco fuel pump, I'm not sure, but I think the pressure shuld be a bit higher with a new pump. No leak in the lines going to or from the tank. No leak inside the thank. No leak at the pump.

But could a leak at the CPI be intermittent? It still has the sulfur smell from the exhaust, not all the time, it comes and goes.
In other word, I have all the signs of a leak, but can't find the leak

And I must add that some mornings, after the engine has been shut off for several hours, the first 0.5-1 sec of cranking is like cranking a flooded engine. Mostly this happens after the engine has not been started after a longer trip the day before.