Tunerpro RT $4F connection problems

[EagleMark]

That is pegged rich a lot, so if you have a vacuum leak the O2 sensor reads all the air and adds fuel, double whammy is MAP see's low vacuum, higher MAP and thinks it's a load and adds fuel. Or fuel pressure is way to high? Is this a stock motor? Something is wrong...

[duecepipes22]

Starter fluid is actually what I originally used until I ran out... OOPS! Wasn't using short bursts! I'll get more and try that again. Could a very minor leak be causing this? My EGR leaked way worse than what I noticed this time and fixing that and the throttle body didn't help at all!

The motor isn't stock. Its got stock heads that were shaved just enough to true them up and intake manifold but then its got an open element filter, mild RV cam, the basic throttle body mods, long tube headers with true duals, H pipe, no cats and glass packs. My fuel pressure should only be at about 13 psi right now, I checked it no too long ago. I've got some ticking from the headers that I thought could be an exhaust leak, but people keep telling me that just how headers sound.

[EagleMark]

All those mods would not cause this and the cam is not big enough. Your MAP reading and idle are fluctuating from 35 to 45 but idle IIRC was only moving about 75 RPM, IAC was low at like 9 to 20 counts. BLM seem to rise as RPM and load increase to where they should be. All indacations of vacuum leak. Hard to do over the internet but looking into vacuum leak is something I would look into.

My headers never ticked? Does this tick happen on O2 sensor side?

I hate to say this but on a SBC you can have a vacuum leak under intake not detectable without a smoke machine. You could pull all plugs and look for one that is differant as well for an individual or pair of cylinders off. In a case like this I would start with four on O2 sensor side.

[duecepipes22]

Well I know for sure one of my TBI base gaskets is still leaking a little, on the O2 sensor side, either above or below the spacer but since I can't seal them up, I'm going to put a bead of silicone around the top and bottom of each gasket to help seal it up... that should take care of it!

Not sure which side the headers tick on, I can only hear it when I'm in the truck and its under a load. They are 14 gauge so I thought the ticking wouldn't happen... maybe it is a leak? I'll look into that a little more.

Boy I hope its not the intake manifold.. Can I check that with the starter fluid or do I have to smoke test it? I did notice a while back when I was checking spark plug gaps that cyliders 6 and 8 looked a little wet. I re gapped them and drove it a little and they looked fine when I checked them again. Not sure what to think about that but I also recently changed plug wires because they were getting bad and since plug wires 6 and 8 were wrapped together, they could have been messing with eachother.

[EagleMark]

Any of or all those things add up to a mechanical issue you can't tune out. Silicone around spacer is not going to do the trick there. You need some new gaskets, clean flat surfaces and O2 sensor safe sealer designed for fuel on both sides. Some fine grit sand paper on a really flat surface and polish all surfaces in circular motion will usually show you a defect that is causing the vacuum leak.

Bottom of intake is inside motor, can't test that with starter fluid... that would be last resort test but have to have a smoke machine to do it. If all machining was done properly it should not happen...

[duecepipes22]

I've tried 2 different sets of gaskets but they haven't sealed up. I'll take them off again and try polishing up the surfaces. So you don't think it would work to put a thin bead of gasket maker between the spacer and gasket and gasket and manifold? By 02 safe sealer do you mean a different sealant to put between there? $6 isn't bad to pay for gasket, but the cost is starting to build up after trying 2 pairs of them and the leak still isn't fixed! I'm just keeping my fingers crossed that its not the manifold leaking!

[EagleMark]

O2 sensor SAFE gasket sealer so the fumes do not ruin the O2 sensor, also has to be fuel contact type. Polish all surfaces on machined type flat surface, machine shops have flat tables, I have a piece of billet alluminum, machined and polished and checked on the flat table at machine shop and use it. Before that I had a 1/2 inch thick aluminum plate that was fine... Look for and keep polishing out inperfections. 5 circles and rotate part 90 degrees, five circles rinse and repeat till you did it 360 degrees, look for inperfections. Start with 300 emery cloth, if you find a big inperfection use 100, then when gone polish with 300. Then a layer of sealer on both sides of gasket. Tighten up and let dry overnight. I don't like doing it this way or all the work but once a gasket leaks once I do this and it never has failed... thank God I never had to take one off too...

[duecepipes22]

I think I got it all sealed up. I put new gaskets above and below the TB spacer and I can't find any spots with the lighter fluid that change the idle. The idle is 75% better now but the tach still has a little bounce to it. I was going to data log today but the computer battery was dead, but hopefully later in the week. I'm going to retorque my intake and header bolts tomorrow and and turn down my fuel pressure a bit to see if any of that helps at all.

[duecepipes22]

Well I tightened my header bolts today, attempted to tighten the intake bolts but realized it was more of a hassle than I realized so I'm putting that on hold, and I decreased my fuel pressure a little bit. I did a data log as you will see attached and I'm not sure if I've gained any progress or not. I was hoping you might be able to tell??? I was also looking at the flow sheet I got when I had my injectors flow matched and I didn't know if the numbers would help you determine why I'm running rich despite using a stock fuel table on a mildly upgraded motor.... injector 1 is 859 cc/min and inj 2 is 861 cc/min @ 20 psi, but I'm running them around 12 psi. I have no idea if that helps or not, but now you know.

[EagleMark]

Still a lot of 105 BLM which is MAX low!

But I just looked at your main fuel VE table and it is WRONG! Corrupt or just a big mistake... from earlier post TPS Tune Bin? Look at your main fuel table in graph mode...

[duecepipes22]

Isn't that the fuel table that you said was identical to the stock one? When you say wrong, are you referring to the fact that it dips way down in the middle?

[EagleMark]

I take that back.. all stock bins for 5.7L $4F Main VE table is WRONG! Corrupt or just a big mistake! How the hell would you tune that? I would have to build a new fuel table before I started with one of these. Here is another GM SCREW UP!!! What a joke...

[duecepipes22]

Uh oh... so now what do I do? If its actually that bad, would the truck even run? Other than the idle, the truck runs fine. In my mind, it lacks power, but it doesn't do anything that would seem problematic. I'll pull the chip again tomorrow and pull the bin off and upload it on here just to make sure something didn't get corrupted.

[EagleMark]

Well nothing there made sense? So I looked at the hack and the XDF is built wrong!

Your still way rich but until this XDF gets a rebuilt I wouldn't know how to take fuel out of VE...

[EagleMark]

I fixed the XDF and took some fuel out of the lower VE table for ya...