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Maybe a few more minds on this topic will help...
I have a Caspers AFPR on my fuel rail right now, I'm running the trailblazer Injectors which are 28# per/hr at 61PSI... I have my pump set for 62PSI at WOT, so all is good there...
Now I have two issues that have to be related and I'm not sure of the source.
1) Hard starting. Never had this issue before up until a few weeks ago, always started quickly, even if it was followed by stalling due to the large cam, but it would fire quick before.
2) Large pressure drop when nitrous fuel solenoid engages. This is where I noticed it the most and it worry's me... its enough of a drop for long enough to have the a/f ratio on my wideband hit 14-16:1 for one line in my log... Yeah short but its still there.
it drops from 63PSI down to about 25 for what seems a split second, but you can feel it.
I have a gauge on my car right now so I can see it driving, I have NO issues at WOT n/a or even just doing a key on prime test... the pressure goes up and stays up there it does not drop of quickly. Yeah it will bleed back down to 0 over 3-4 hours but that can't be my issue.
I just tested and when I start it jumps to 60 and stays there while cranking... so its not the similar symptom of no pressure while cranking because the pump primed and the regulator didn't hold it.
Now the nitrous setup, its a line that taps off of my pressure valve on my rail, and by the coil pack and down to a solenoid that's on the other side of the brakes, then there is a 18" line to the nozzle that's in the TB spacer. I'm assuming this drop in pressure is due to filling the long source line of any air pockets, and also filling the 18" up to the jet in the nozzle... Back to back engagemnt of the fuel solenoid does not produce the same drop, its only the first one say ever 5 min or something, so I'm assuming by the the 18" line is sucked dry from the vaccum of the motor since thats after the solenoid.
Either way the only thing that comes to my mind is fuel FLOW being an issue... I have a 255lph walbro HP pump, and I had to modify my bucket to make it fit...
PIC
The pump has direct access to the bottom of the tank so its not stuck in the factory bucket that could be drained quickly... I'm thinking and hoping, the rubber line I used was a little long, you need to compress the springs on these pickups to get them down and in, and I'm HOPING TO GOD that the rubber line just got softer and kinked a little and is restricting flow...
I've also purchased a new fuel filter, since I did change that when I did my tank but it was a god who knows how old filter I had lying around...
The hard starts did not start happening right after I installed this pump, it actually fired REALLY quick the first time after setting this all in, and I figured it would crank more the since the line was empty.
I want to say this all started a few weeks after I did the pump... so thats why I'm thinking something changed in there due to that excess compression and I hope its nothing I can't fix quickly.
I have a Caspers AFPR on my fuel rail right now, I'm running the trailblazer Injectors which are 28# per/hr at 61PSI... I have my pump set for 62PSI at WOT, so all is good there...
Now I have two issues that have to be related and I'm not sure of the source.
1) Hard starting. Never had this issue before up until a few weeks ago, always started quickly, even if it was followed by stalling due to the large cam, but it would fire quick before.
2) Large pressure drop when nitrous fuel solenoid engages. This is where I noticed it the most and it worry's me... its enough of a drop for long enough to have the a/f ratio on my wideband hit 14-16:1 for one line in my log... Yeah short but its still there.
it drops from 63PSI down to about 25 for what seems a split second, but you can feel it.
I have a gauge on my car right now so I can see it driving, I have NO issues at WOT n/a or even just doing a key on prime test... the pressure goes up and stays up there it does not drop of quickly. Yeah it will bleed back down to 0 over 3-4 hours but that can't be my issue.
I just tested and when I start it jumps to 60 and stays there while cranking... so its not the similar symptom of no pressure while cranking because the pump primed and the regulator didn't hold it.
Now the nitrous setup, its a line that taps off of my pressure valve on my rail, and by the coil pack and down to a solenoid that's on the other side of the brakes, then there is a 18" line to the nozzle that's in the TB spacer. I'm assuming this drop in pressure is due to filling the long source line of any air pockets, and also filling the 18" up to the jet in the nozzle... Back to back engagemnt of the fuel solenoid does not produce the same drop, its only the first one say ever 5 min or something, so I'm assuming by the the 18" line is sucked dry from the vaccum of the motor since thats after the solenoid.
Either way the only thing that comes to my mind is fuel FLOW being an issue... I have a 255lph walbro HP pump, and I had to modify my bucket to make it fit...
PIC
The pump has direct access to the bottom of the tank so its not stuck in the factory bucket that could be drained quickly... I'm thinking and hoping, the rubber line I used was a little long, you need to compress the springs on these pickups to get them down and in, and I'm HOPING TO GOD that the rubber line just got softer and kinked a little and is restricting flow...
I've also purchased a new fuel filter, since I did change that when I did my tank but it was a god who knows how old filter I had lying around...
The hard starts did not start happening right after I installed this pump, it actually fired REALLY quick the first time after setting this all in, and I figured it would crank more the since the line was empty.
I want to say this all started a few weeks after I did the pump... so thats why I'm thinking something changed in there due to that excess compression and I hope its nothing I can't fix quickly.
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