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No compression check yet. I decided to the water test again. Sprayed water here and there and the throttle shaft. Made no difference. Soaked the top of the motor... and nothing. Pinched off line to power brake and line to the pcv valve. I can not find this leak. There is a line going to the passenger side of the throttle body that if I pull the line of and hold my fingers over the openings... the STFT's would go even higher till I put the hose back in it's spot.
Baffled in the worse way on this. I even rechecked the fuel pressure and it was still good, 50 to 59 psi.
that line is part of the crankcase ventilation system. it connects to the valve cover on the passenger side of the engine (kind of like the old breather cap). it works in conjunction with the pcv which is connected on the other side of the engine. the ccv is a closed system. if you unplug it, you create an air/vacuum leak as you found out. make sure its connected at the throttle body and valve cover and has no leaks. a leak should have shown up when you doused the engine with water but maybe not.
does the truck have the stock air box system?
"an open mind let's knowledge flow in and wisdom flow out for a man who has neither never listens to those who have both".
Being wrong doesn't bother me, it's being right and not understanding why that does
Thanks SJ it was weird because when I took the tube off I plugged the hole with my thumb and covered the nipple with my finger and it still trims went high. I didn't think it would still do it with me covering the holes. I don't know man... it's almost like it supposed to run at 25% on the long terms... lol. No, cause it runs like crap.
On the compression question, ideally you'd take all of the plugs out, hold the throttle to the floor, and crank until the needle bounces about five times. The reading will only go so high. You do each cylinder and compare the readings. You want them within about 15% of each other.
Here's those compression numbers. Bank 1# 1= 120psi, #3= 135psi, #5= 145psi, #7= 120psi. Bank 2 #2 120psi, #4= 120psi, #6= 130psi, #8= I couldn't get the hose to screw on
Interesting that #5 has the highest number, which is more than 15% of the 120 on the others. I'll let someone else interpret that, since my experience has always been having one or a few lower than the group. I'm not sure if it makes a difference or not.
I think I asked that poorly... does the truck use the standard air filter box and snorkel to the throttle body or does it have an aftermarket K&N setup.
Did you notice that ScannerDanner was posting on other problems? I was hoping that he might see your problem and offer some advice.
"an open mind let's knowledge flow in and wisdom flow out for a man who has neither never listens to those who have both".
Being wrong doesn't bother me, it's being right and not understanding why that does
Sorry SJ I meant I have no aftermarket stuff on it and just a regular air filter. If ScannerDanner would have some direction I'd appreciate it. Cause everything is what it should be... but it isn't. No restrictions in the fuel line, new fuel filter, new fuel pump, new injectors, new MAF and MAP, new plugs wires and coils... Fuel pressure is on spot in park 50 to 59 psi when revving. Have yet to extend the fuel hose to see fuel pressure as I'm driving. Passes the smoke test, the carb cleaner test, the brake cleaner test, the water test... I'm at a total loss. I'm like to the point I'm thinking the MAF isn't reading right because of the connector. I don't own a scope yet. Worked on it over the summer to get it ready for this winter and that was a fail... lol. I also changed the intake manifold gaskets.
Once the weather stops raining here I'm going to smoke test the exhaust. It's gotta be something like that. I stuffed a rag in the tailpipe and held it there. I was working alone so I really couldn't hear nothing. Maybe I have a exhaust leak at the head or something. No matter where my throttle is the average fuel trim holds around 25% and 23%. Maybe I need to pull out the garden hose and spray the motor down all over. When I did it before it was with my pop bottle squirter. Maybe there wasn't enough coverage in just using that.
Ok... just to be sure... as the LTFT head to zero, the STFT was counting upward keeping average around 25% between the long term and short term fuel trims values together
