89supracrazy;1535403 said:
Next time save yourself a few moments and just put your pedal to the floor. Do not pump the pedal.
DTC?
Why? You think the impedance is wrong? You simply unplugged it or bypassed it?
VF signal
- Thread starter 89supracrazy
- Start date
Next time save yourself a few moments and just put your pedal to the floor. Do not pump the pedal.
DTC?
Why? You think the impedance is wrong? You simply unplugged it or bypassed it?
I tried holding the pedal to the floor with no results. I unplugged the resistor pack because that kills your injectors. I had so much fuel built up it would not fire until I burnt what was inside the chamber first. It ran for a about 10 seconds before it died. Once that happened I plugged my resistor pack back up and it fired right up but smoke alot for about 2 min. I have the precision 550 injectors that I installed myself. What can cause this. Is it the bigger injectors. I had a problem last year at the track after I installed the 550. If I ran down the track and shut my car off it would not start unless I kept tapping on the main relay. I figured out the only thing I was doing was breaking the circuit when hitting the relay. So this time I unplugged my resistor pack with better results. Too much fuel my car cant burn. Is it ignition problems not burning the fuel or something else. I can do the same thing right now just bump my car about 5 to 6 times and it wont hit at all until I unplug my resistor pack.
After seeing this thread and recently (3 days ago) installing the lex/550 upgrade into my car also using the factory FPR I decided I would check my Vf's to see how they compared to the OP. My car has about 100 miles on it since the upgrade, but only about 30 miles since I last pulled the EFI fuse to reset the ECU learn function. I also have an innovate wideband to compare how the car's A/f's have changed from stock fuel to the lex upgrade.
Couple points
1) both with the lex/550 and all stock my car idles, and cruises down the hwy with AFR's varying between about 14.1 and 15.4 afr, which I think is just about perfect
2) under boost (4-5 psi+) AFR goes down to 10.6-12 afr based on rpm and throttle position. Above 3-3.5 k afr's are 10.6-11. This is with stock turbo going up to 10-15 psi of boost.
3) the car drives and behaves identically to how it did with the factory components with the Lex/550 upgrade
With all of the above known, I checked my Vf's at idle (lex screw has not been tampered with and is still "sealed"). My idle VF is 5V exactly, however my car runs Af's which I am happy with under all conditions I have tested it in. I measured Vf at ~2500 rpm free revving and it was still 5V. I currently do not have a way to see what VF is during cruise but may get some wires fed through the hood and window to check in the near future. Unfortunately I never checked my vf's with the factory components.
I have an Aeromotive AFPR that I was going to install but had a problem with the braided return line being to close to my wiring so until I get some new AN fittings it is not going to be installed. But after running this way I am very happy with the factory FPR and the A/f's I see so it may be a while until I put in the Aeromotive AFPR. I already have an MKIV denso pump and that will be installed in the next couple of weeks.
To the OP, I would get a wideband to see what your actual a/f's are, I see that is your plan, but I would do it sooner rather than later. With regard to your recent problems, I have no idea what to tell you. I have never had my car exhibit any of your starting symptoms, ever...
Couple points
1) both with the lex/550 and all stock my car idles, and cruises down the hwy with AFR's varying between about 14.1 and 15.4 afr, which I think is just about perfect
2) under boost (4-5 psi+) AFR goes down to 10.6-12 afr based on rpm and throttle position. Above 3-3.5 k afr's are 10.6-11. This is with stock turbo going up to 10-15 psi of boost.
3) the car drives and behaves identically to how it did with the factory components with the Lex/550 upgrade
With all of the above known, I checked my Vf's at idle (lex screw has not been tampered with and is still "sealed"). My idle VF is 5V exactly, however my car runs Af's which I am happy with under all conditions I have tested it in. I measured Vf at ~2500 rpm free revving and it was still 5V. I currently do not have a way to see what VF is during cruise but may get some wires fed through the hood and window to check in the near future. Unfortunately I never checked my vf's with the factory components.
I have an Aeromotive AFPR that I was going to install but had a problem with the braided return line being to close to my wiring so until I get some new AN fittings it is not going to be installed. But after running this way I am very happy with the factory FPR and the A/f's I see so it may be a while until I put in the Aeromotive AFPR. I already have an MKIV denso pump and that will be installed in the next couple of weeks.
To the OP, I would get a wideband to see what your actual a/f's are, I see that is your plan, but I would do it sooner rather than later. With regard to your recent problems, I have no idea what to tell you. I have never had my car exhibit any of your starting symptoms, ever...
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89supracrazy;1535960 said:
Holding the pedal to the floor goes into clear flood mode. You didn't do it long enough.
Work on your wording. I was going to ask just how it kills the injectors, because it does no such thing. Unplugging it takes power from them. Then I realized that is what you are trying to say.
So every time you start it you get heavy smoke for 2 minutes?
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Ok I had to try something with my stock regulator and here is my results. I had 4.7 at idle now I have 2.0 at idle. What I did was take the union bolt out of the regulator and it has two holes in the side of the bolt, so I figured I would try to solder one of the holes up to see if it would make a difference. I have no vacuum on the regulator. If I put vacuum on, it will go back to 4.7. Let me here some feedback.
89supracrazy;1538515 said:
I would recommend not doing either of those things. You need vacuum hose/reference on the regulator so that under boost Fuel pressure increases at a 1:1 ratio to boost. I myself would never modify a union bolt either.
Also, I think you need to just get a wideband and stop modifying things that should not be modified, and modifying them without correct knowledge on how they operate and affect the overall system. You do realize that A/f at idle and cruise, which is what VF mostly reflects (if the ECU is able to adjust to Stoich) is really not very important compared to A/F while in open loop (ie full throttle). Your effort to improve your VF number has severely hindered your actual AF under WOT, which you still do not accurately know and your "modification" has made worse. I would not boost the car or drive it the way it is currently set up. My $.02
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I agree that I need to get the proper equipment, but I just like to see if it makes any difference. How does the fuel pressure increase with more vacuum. I was under the impression that at wot that the vsv shuts off the vacuum to the regulator and that increase fuel pressure. The tsrm says at idle it is low pressure with vacuum and it is 33-40 with no vacuum. Im I thinking wrong.
89supracrazy;1538544 said:
Under vacuum the fuel pressure is lower than at Atmospheric pressure. However fuel pressure goes up even higher when the regulator reference/vacuum line is under boost. So yeah at idle you have increased the Fuel Pressure making it run more rich and lowering the VF output in the diagnostic block. However, since the ECU thinks that FP is going to go up at a 1:1 ratio under boost you will go LEAN and bad things will happen.
GET A WIDEBAND BEFORE DOING ANYTHING ELSE
89supracrazy;1537224 said:
20 seconds is not going to burn your starter. You must let it cool at that point. As you have notice, that is a symptom of a problem.
Hook up a fuel pressure guage. Get pressure so it runs. Then watch how fast it drops. You could have an injector bleeding down.
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I just replaced the injectors with brand new ones about a year ago. When I turn the ignition to the on position and press my throttle to the floor my safc says about 97 percent. Do I need to adjust the throttle cable. Do you think that it could cause it not to go into clear mode when I hold the throttle to the floor. I do need to check my fuel pressure. I do not have a guage right now. Do you know where I can maybe purchase a guage.
You need this adapter for the CSI fitting, and then any standard fuel pressure gauge should fit.
http://www.actron.com/product_detail.php?pid=16215
http://www.actron.com/product_detail.php?pid=16215
just found out that if you put the screw all the way in, it will leak air through it. make sure it is not doing this. i put the screw all the way in and then back it out a 1/8 of a turn to seal it up.