fuel pressure

[Joeld]

I understand your point, as a newbie it is hard to imagine a car with 17K can't be tuned without parts being replaced? Were they untunable brand new? i'm guessing the answer is yes or there'd be no hotwire kits and the like. This weekend will be spent on fuel pump and hotwire.
Hoping the day may come when I can take the family for a ride
Joel

 

[Ttype6]

I have stock chip, stock injectors, stock fuel regulator. I was hoping to get her tuned prior to replacing fuel pump, installing manual regulator and hotwire kit. Maybe not possible? Or maybe my injectors are dirty?

Joel

845 leads us to believe that you are getting enough fuel.

 

[Joeld]

Thanks Ttype6, maybe quality of fuel then? I get that I should be installing hotwire and fuel pump regardless, but I'm trying to sort out as much as I can when I have the time to do it. and swapping out fuel pump will take some time. anyway, the help is always appreciated. I put in 93 octane the other day, but I did not drop and flush tank so chance that there is a trace of old fuel. Joel

 

[Ttype6]

Were they untunable brand new? i'm guessing the answer is yes or there'd be no hotwire kits and the like. This weekend will be spent on fuel pump and hotwire.

You should be able to run 17 lbs of boost with 93. You haven't proven that your fuel supply is lacking. What is the BLM number at an idle?

 

[Joeld]

thank you for continued help i will get all numbers at idle tonight after work
i would be happy as a clam running 17 pounds i am trying to keep the car as low key as possible just want it to run well and strong for a long time
joel

 

[Joeld]

At idle
o2 - 175 - 738
AF - 06
L8 - 45
bat - 14.1
int - 125-135
bl - 138
mph - 0
clt - 178
ats - 54
r - 725
tps - .42
iac - 28
cc - 71
mal - 31 - code i've not yet cleared, was a blown sol fuse that I replaced and has not blown again.

Looking forward to what you all think these number mean. I've read the vortex buicks write up, nothing seems to crazy out of line to the untrained eye?

Thanks,
Joel

 

[Ttype6]

At idle
o2 - 175 - 738
AF - 06
L8 - 45
bat - 14.1
int - 125-135
bl - 138
mph - 0
clt - 178
ats - 54
r - 725
tps - .42
iac - 28
cc - 71
mal - 31 - code i've not yet cleared, was a blown sol fuse that I replaced and has not blown again.

Looking forward to what you all think these number mean. I've read the vortex buicks write up, nothing seems to crazy out of line to the untrained eye?

Thanks,
Joel

You have O2 numbers in the 840s and now you have BLM numbers right where they should be. 128 is the default BLM number. If you see a number higher than this,it means the computer is adding fuel. If you see a number lower than 128,the computer is taking away fuel.These two bits of evidence tell us that the fuel pressure is where it should be. If this is true,the gauge would be the first thing to suspect. If you have two gauges,compare the idle numbers of both gauges. If both gauges are the same,your fuel pressure is where it needs to be. If your motor makes 11 lbs of boost,you should see 46 lbs of fuel pressure. Do you? Have you replaced the air filter?

 

[Ttype6]

Crap,I mixed up your blm and INT numbers. 138 means the computer is pulsing the injectors about 8% longer that the program thinks the motor should be needing. Vacuum leak,low fuel pressure,bad MAF. Anywhere air can enter the intake after the MAF would cause the computer to add fuel. Have you inspected the intake hose?

 

[we4Mateo]

If you're running a stock chip, that will cause knock as the timing is WAY too aggressive for today's gas. Get a turbotweak or bailey chip to get the right timing in it, but you'll need an adjustable fuel regulator for both as they require higher base fuel pressure than stock. You'll need it with the hotwire and a good pump anyway. You may have a low mile car, but yes, the electrical and fuel systems were barely adequate when new with good gas. Now gas blows and your electrical system, like everything else, is still old and underdesigned despite the lack of use.

 

[Joeld]

thank you guys
i will get another guage and check readings
i will also install hotwire and fuel pump and regulator
i will then post fresh readings both pressure and scanmaster
I did look over the intake close closely when I removed to install new air cleaner and pulling the intercooler and doing the serpentine belt and the like, it looked good to me.
I am running the stock chip.
joel

 

[Ttype6]

thank you guys
i will get another guage and check readings
i will also install hotwire and fuel pump and regulator
i will then post fresh readings both pressure and scanmaster
I did look over the intake close closely when I removed to install new air cleaner and pulling the intercooler and doing the serpentine belt and the like, it looked good to me.
I am running the stock chip.
joel

You still haven't proven that your fuel supply is inadequate. 93 octane is 93 octane. Which is heavier,a lb of feathers or a lb of bricks. The number 93 tells you how resistant the fuel is to autoignition. It has the same resistance as it did years ago. How do I know? Because of the number 93.

 

[Joeld]

i thought the 138 blm was a possible indication of lack of fuel pressure?

 

[Ttype6]

i thought the 138 blm was a possible indication of lack of fuel pressure?

Correct,lets see what another gauge says. Didn't you tell me that you also had a rail mounted gauge?

 

[Ttype6]

i thought the 138 blm was a possible indication of lack of fuel pressure?

It shows a possible lack at idle,but it doesn't mean your pump isn't up to the task of supplying you motor with enough fuel at it's current power level.. This might mean a broken spring in the regulator,but we first need to see what another gauge says. The 845 leads us to believe that we have enough fuel at WOT,however we haven't proven that yet either. I'd like for you to get an understanding of the theory of operation of your electronic fuel injection. Again,you need to know the idle fuel pressure(line off) and the pressure at 11 lbs of boost. According to your gauge showing 35 lbs at an idle,you should see 46 at 11 lbs of boost. Do you know if this is the case?

 

[Joeld]

first you guys grilling me for detail and forcing me to understand and learn rather than just answering qiestions is invaluable to me!!!!

ok i have fuel rail guage hooked it up and it leaked big time. i am currently using free autozone rental. i will get second by the weekend

i am seeing, on that autozone guage 25 idle with vacuum 35 or so without vacuum and 36 or so with vacuum and about 10-11 pounds of boost based on guestimate from stock boost guage. i started to install vdo boost giage last night

that is about where i am at.

 

[Ttype6]

first you guys grilling me for detail and forcing me to understand and learn rather than just answering qiestions is invaluable to me!!!!

ok i have fuel rail guage hooked it up and it leaked big time. i am currently using free autozone rental. i will get second by the weekend

i am seeing, on that autozone guage 25 idle with vacuum 35 or so without vacuum and 36 or so with vacuum and about 10-11 pounds of boost based on guestimate from stock boost guage. i started to install vdo boost giage last night

that is about where i am at.

36 while the turbo is making 11 lbs of boost?

 

[Joeld]

the best i can tell with limited insrumentation

yes

 

[Ttype6]

the best i can tell with limited insrumentation

yes

That's a problem. Even if your gauge is wrong,it should still rise one to one with the boost.

 

[Joeld]

it went from 25 to 36

 

[Ttype6]

it went from 25 to 36

When we check for a 1 to 1 rise in fuel pressure we start from the idle pressure number we see when the vacuum line is disconnected from the fuel pressure regulator. That number,for your car,is 35. This means that at 11 lbs of boost you should see a number 11 numbers above 35. That would be 46. Your pressure isn't rising at all.