Car goes instant lean as soon as the boost gets to 10ish... Your not getting the FP rise as the boost goes up it appears
12 Degrees Knock Retard @ 13# Boost...WTF?
- Thread starter zhorner
- Start date
Car goes instant lean as soon as the boost gets to 10ish... Your not getting the FP rise as the boost goes up it appears
looking at it on PL frame x frame FP goes up with boost then flat lines when boost levels do...albeit FP is a little low. I turned it up some and will put it to the test again.
I was just reading the manual for my TT 6.1 chip and it says for alcohol users their is a timing delay after you hit the gas pedal to reduce knock prior to the alky spraying...that instant lean could be where the chip expects to see methanol and really ups the timing?
edit: lol just read my own signature and it says I have a 6.0 chip. Cars been broke down for so long Im not ever sure what I have.
edit: lol just read my own signature and it says I have a 6.0 chip. Cars been broke down for so long Im not ever sure what I have.
Pronto
Believe nothing you hear and half of what you see.
- Joined
- Dec 9, 2002
The chip has nothing to do with the fuel pressure. Pump, filter, lines and fuel pressure regulator need to checked and tested. Wouldn't be surprised if you have a leak in the rubber line connecting the pump to the fuel sender.
I see what you are saying, timing delay or not...its going lean. Ill start with the filter since I know it hasn't been changed in the 4 years I have had the car.
Fuel filter will be getting replaced. What gap would you recommend?
signal hose is very tight, not zip tied though. Just filled the tank up 5 minutes before this happened. Good idea on the tank vent...I never hear a hiss when removing the cap but I can loosen it to see if it is causing the issue. Fuel filter is getting replaced either way.
- Joined
- May 28, 2001
Charcoal can still on and hooked up?
Or, are the hoses off and plugged? If so, there's no tank vent.
Best to get the basics done, B4 you do more of that 12* KR...You'll be putting on head gaskets, or worse.
tysongross
Mississippi Mayhem
- Joined
- Apr 13, 2011
Check the return fuel line also. Could be blocked / clogged. That made my fuel pressure drop under boost.
Jerryl
Tall Unvaccinated Chinese Guy
- Joined
- Dec 14, 2004
Fwiw . . Regarding tank venting.
Completed a backyard fuel flow test a while back when replacing the tank. Ran the pump while the tank was out to empty the tank.
There was a very noticiable difference in pump sound and flow when the cap was removed, even with the vent at the hanger wide open. Unfortunately . . . I lost the video of it.
Now, I realize there was no tuel returned to assit with the pressure drop in the tank but it told me quite a bit if you are trying to run the pump close to full flow capacity. . . .
Completed a backyard fuel flow test a while back when replacing the tank. Ran the pump while the tank was out to empty the tank.
There was a very noticiable difference in pump sound and flow when the cap was removed, even with the vent at the hanger wide open. Unfortunately . . . I lost the video of it.
Now, I realize there was no tuel returned to assit with the pressure drop in the tank but it told me quite a bit if you are trying to run the pump close to full flow capacity. . . .
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I was doing some research on this after you mentioned it and found that autozone usually stocks vented gas caps part # 6817. What are your thoughts on that?
- Joined
- Feb 18, 2006
Strange. Almost looks like the vac/boost line blew off the fpr.
Does it show knock if you run it up with no boost?
Rick
Does it show knock if you run it up with no boost?
Rick
Jerryl
Tall Unvaccinated Chinese Guy
- Joined
- Dec 14, 2004
Not sure if I am qualified to give a concrete technical answer as there are too many variables to consider.
You need just enough venting to ensure it does not negaitively impact pump performance/fuel delivery. Venting requirements are really dependant on the setup and operating conditions.
If you crack the cap and it does not show impact on fuel delivery, I would not worry about it at this point and focus on other things. If anything, I would start with an oem cap and verify the check valve direction to the canister . . .
There are systems out there that can regulate tank pressure to 0.5 or less psi. But that is another project I may work on some day. Lol
no it doesn't. just changed the fuel filter and it did the same thing. then cracked the cap open with no luck there either.
