I have direct scan and it is only showing 50% at WOT. That is not normal is it??? I have 40 psi inj and i have the fuel pressure regulator screwed almost all the way down to keep det. away which gives me a ton of psi. My fuel pressure guage is broken so i don't know what the pressure is. I can email somebody on of my runs if you want to see what is going on. It is also surging on me too now.
Injector pulsewith and other problems.
- Thread starter dfast1
- Start date
- Joined
- May 28, 2001
FPR SCREWED DOWN???
Whoa there!! Lets start from the beginning!!
1. GET A GAUGE B4 you blow the motor.
2. Set the press. to 42, line off.
3. Hook up the ga. and w/ the boost turned down to 14psi, make a short WOT run and record the data, and watch the Fp. It best be at 42+ boost of 14= 56PSI, once boost is attained. If you see it's NOT keeping up w/ boost rise, SHUT IT DOWN.
What else has been done to the car? Turbo, etc????
You HAVE to cure the knock w/ the engine properly tuned BEFORE you try to use added fuel press. for anything.
As for 50%, that may be the case if the engine is flooded w/ fuel due to astronomical fuel pressure.
SLOW DOWN and tell us ALL you know about how the car is built, how it's tuned, etc and we'll go from there.
Whoa there!! Lets start from the beginning!!
1. GET A GAUGE B4 you blow the motor.
2. Set the press. to 42, line off.
3. Hook up the ga. and w/ the boost turned down to 14psi, make a short WOT run and record the data, and watch the Fp. It best be at 42+ boost of 14= 56PSI, once boost is attained. If you see it's NOT keeping up w/ boost rise, SHUT IT DOWN.
What else has been done to the car? Turbo, etc????
You HAVE to cure the knock w/ the engine properly tuned BEFORE you try to use added fuel press. for anything.
As for 50%, that may be the case if the engine is flooded w/ fuel due to astronomical fuel pressure.
SLOW DOWN and tell us ALL you know about how the car is built, how it's tuned, etc and we'll go from there.
My sig shows what all i have done to the car. Here is why kept upping the fuel pressure. I was getting a lot of retard {3-10'}so i would increase fuel pressure which would make the it go away. I am running 15 pds of boost on 92 octane. What should i be looking for in the o2 volts?? What numbers should i be looking for to tune with? I won't run anymore till i get the FP guage and set the pressure like you said. What should my inj. pulse with be at WOT?
What keeps detonation away is octane, not fuel volume (unlesss you're running too lean). I would imagine you're running so much fuel pressure as to be drowning the engine. The BLM's must be WAY LOW. This is probably what's driving your injector PW so low (~ 50%)
3-6 degrees of knock retard isn't going to be damaging unless it's constant. 3-6 at the shift points is fairly common in street trim, and 15# of boost on 92 octane is about as much as can be expected with gas formulations going into the crapper like they are.
You need to get your fuel pressure back to normal, and tune carefully. Too much fuel pressure (cranked way high like yours) can be a very bad thing. Could in extreme conditions lead to injector lock
too much fuel washing down the cylinders
etc.
A static (hose off) idle fuel pressure of somewhere around 42-44# should be more than sufficient!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
3-6 degrees of knock retard isn't going to be damaging unless it's constant. 3-6 at the shift points is fairly common in street trim, and 15# of boost on 92 octane is about as much as can be expected with gas formulations going into the crapper like they are.
You need to get your fuel pressure back to normal, and tune carefully. Too much fuel pressure (cranked way high like yours) can be a very bad thing. Could in extreme conditions lead to injector lock
too much fuel washing down the cylinders
etc.
A static (hose off) idle fuel pressure of somewhere around 42-44# should be more than sufficient!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Got a fuel pressure guage on it and i had it set to around 65 psi. Lowered with vac. line of to 42 psi and it ran MUCH MUCH BETTER!! Inj. pulsewith went up and there was no surging. I was hoping to be able to run more boost with my front mount intercooler. I am still tuning. I need MORE TIPS on what i need to look for in Direct Scan to tune it right. What is inj. lock? Also what is knock count? How is different from knock retard. What should my blm's be like? 02 volts?? thanks for the help so far.
blackbuick87
Senior Member
- Joined
- Mar 11, 2002
65PSI
Check your oil first it may be full of gasoline
Knock count is the number of times the knock sensor "Hears" the engine knocking in a given amount of time. Knock retard is the number of degrees of ignition timing the computer pulls out to stop the knock. If you have a high KC and low KR, you have a consistent problem like running lean. If you have low KC and high KR something is causing a large spike like shifting or a DP hitting the frame possibly.
o2 numbers should be close to 800 at WOT. Dont pay attention to them at part throttle.
Check your oil first it may be full of gasoline
Knock count is the number of times the knock sensor "Hears" the engine knocking in a given amount of time. Knock retard is the number of degrees of ignition timing the computer pulls out to stop the knock. If you have a high KC and low KR, you have a consistent problem like running lean. If you have low KC and high KR something is causing a large spike like shifting or a DP hitting the frame possibly.
o2 numbers should be close to 800 at WOT. Dont pay attention to them at part throttle.
Remember to reset your ECM by unplugging the orange wire behind the battery. That will reset your BLM's to 128 to make tuning possible since yours are most likely way off from running too much fuel pressure.
as stated earlier, your O2 volts should be approx .800 at WOT. Your BLM's by default will be 128, but will vary from about 118 to 138 if everything (namely the fuel pressure) is correct. When looking at the text mode screen, you will see all of the BLM's, the upper left is idle and the lower right is full throttle. Also check that your TPS is set for .42-.44 at idle with engine not running, and at least 4.5v at full throttle (from the gas pedal inside the car, not from under the hood). While your at it, you may as well set your IAC to read from 15-35 while idling. This is done by adjusting what looks like the idle adjustment screw by the throttle linkage. If you move it much you need to readjust your TPS again.
as stated earlier, your O2 volts should be approx .800 at WOT. Your BLM's by default will be 128, but will vary from about 118 to 138 if everything (namely the fuel pressure) is correct. When looking at the text mode screen, you will see all of the BLM's, the upper left is idle and the lower right is full throttle. Also check that your TPS is set for .42-.44 at idle with engine not running, and at least 4.5v at full throttle (from the gas pedal inside the car, not from under the hood). While your at it, you may as well set your IAC to read from 15-35 while idling. This is done by adjusting what looks like the idle adjustment screw by the throttle linkage. If you move it much you need to readjust your TPS again.
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