Breaker 1-9,, how 'bout it longduck, copy ?
03-14-04, 12:01 PM
#1
Tennis, anyone
Thread Starter
Breaker 1-9,, how 'bout it longduck, copy ?
Lol,,,,, I've replaced the fuel filter(s) and have even by-passed the fuel filters. engine idles smooth @ 850 RPM
spin it up a bit and the missing starts, not alot, but it misses, still have low fuel presure. i have not checked the voltage @ the fuel pump. i have even connected the main fuel line to the return line , to make a closed circle, fuel presure goes up. when i removed the injectors the gas colour was dirty as was the inside of the delivery pipe. i've replaced most of all the hi-presure
fuel lines but not any vacum lines(yet) i pull the fuel presure vacum line and nothing changes. i know better then to turn any of the EGI adjustments, TPS,cold hi-idle,
and even the idle. it idles @ 850 rpm right on the money.
turn on the A/C ,the idle goes to 1000 rpm right where i set it before. the 6th ports work smooth too. all electrical connections are connected and all vacum hose
are where they belong. i'm thinking injectors..oh and there are no leaks anywhere(fuel) i've been to the junkyards many times when -SE's were there, always pulled the igniters and pocketed them, never thought to pull injectors for a back-up set, i know now, and thats the junkyard mission,,,no -SE's........my luck,,,longduck Lol
spin it up a bit and the missing starts, not alot, but it misses, still have low fuel presure. i have not checked the voltage @ the fuel pump. i have even connected the main fuel line to the return line , to make a closed circle, fuel presure goes up. when i removed the injectors the gas colour was dirty as was the inside of the delivery pipe. i've replaced most of all the hi-presure
fuel lines but not any vacum lines(yet) i pull the fuel presure vacum line and nothing changes. i know better then to turn any of the EGI adjustments, TPS,cold hi-idle,
and even the idle. it idles @ 850 rpm right on the money.
turn on the A/C ,the idle goes to 1000 rpm right where i set it before. the 6th ports work smooth too. all electrical connections are connected and all vacum hose
are where they belong. i'm thinking injectors..oh and there are no leaks anywhere(fuel) i've been to the junkyards many times when -SE's were there, always pulled the igniters and pocketed them, never thought to pull injectors for a back-up set, i know now, and thats the junkyard mission,,,no -SE's........my luck,,,longduck Lol
03-14-04, 02:01 PM
#2
Old [Sch|F]ool
LOL I thought this was going to be a thread about CB Radios. 
- Pete (That's what the weird brackets on the side of my instrument cluster and trans tunnel are for... )
- Pete (That's what the weird brackets on the side of my instrument cluster and trans tunnel are for...
)
03-14-04, 02:59 PM
#3
Mark,
What is your fuel pressure? It should be around 28.5 psi at idle when the gauge is teed into the line. Also, the fuel pressure should be 50 to 70 psi directly out of the pump. I
f the measurement out of the pump is low, it is likely to be either the pump or the fuel pressure regulator at the pump. If the measurement out of the pump checks out, then either the fuel pressure regulator on the rail is bad or an injector is stuck open. I would think the the pressure regulator would be more likely since a stuck injector would cause lots of flooding.
Kent
What is your fuel pressure? It should be around 28.5 psi at idle when the gauge is teed into the line. Also, the fuel pressure should be 50 to 70 psi directly out of the pump. I
f the measurement out of the pump is low, it is likely to be either the pump or the fuel pressure regulator at the pump. If the measurement out of the pump checks out, then either the fuel pressure regulator on the rail is bad or an injector is stuck open. I would think the the pressure regulator would be more likely since a stuck injector would cause lots of flooding.
Kent
03-14-04, 10:54 PM
#5
84SE-EGI helpy-helperton
As you stated in your post, when you shunt the fuel feed to the fuel return (and I assume you have a pressure gauge on the feed side) then fuel pressure goes up, and back to normal. This is correct, but if it goes down when you have the fuel lines attached to the rail, then it must be something within the rail. If you remove either the FPR or the Pulsation Dampner (PD), then you should be able to see into the length of the rail to look for any obstructions. Additionally, with the injectors removed, you can look up into the rail to look for any sludge that may be ruining your fuel pressure. As someone said above, if the injectors were leaking down, your pressure would drop, but your engine would also be running very rich, if not flooded.
The fuel pressure should be about 30psi at idle, and jumping up to about 45psi when you blow into the FPR diaphragm (attached to the rat's nest). As explained to me, when the engine is under heavy throttle, pressure is routed to the FPR, which shuts off part of the return line flow, effectively raising fuel pressure. If your FPR is bad, it may be bypassing some of your fuel pressure all the time, resulting in low pressure - which would also explain a lean acceleration 'miss'.
Blow air into the fuel pressure regulator vacuum tube to see if this affects engine operation.
If your fuel system is clean, no obstructions, and your fuel pressure lines are good (specifically FUEL INJECTION HOSE, and not 'Fuel Line' - for safety's sake...), then the FPR may be the problem. There are tests in the FSM for the FPR, so give those a shot. My initial assessment in the other thread suggesting the fuel filter, was due to your low pressure - a clogged filter will substantially reduce fuel pressure throughout the system, leading to lean mixture and missing.
As to fuel injectors, cleaning, flow-balancing, and spray-patterning fixed an intermittent and annoying idle problem with my SE last year. If you have any spare injectors to swap, that may help diagnose the problem. Not all injectors are created equal, however - so you're looking for Orange Top, 680cc flow, SE-injectors. You can also test injectors with them installed on the car, if you look in the FSM - this requires wiring them to the rail and testing with the fuel pump shunt installed.
Good luck, and reply back when you get a chance to try a few things,
The fuel pressure should be about 30psi at idle, and jumping up to about 45psi when you blow into the FPR diaphragm (attached to the rat's nest). As explained to me, when the engine is under heavy throttle, pressure is routed to the FPR, which shuts off part of the return line flow, effectively raising fuel pressure. If your FPR is bad, it may be bypassing some of your fuel pressure all the time, resulting in low pressure - which would also explain a lean acceleration 'miss'.
Blow air into the fuel pressure regulator vacuum tube to see if this affects engine operation.
If your fuel system is clean, no obstructions, and your fuel pressure lines are good (specifically FUEL INJECTION HOSE, and not 'Fuel Line' - for safety's sake...), then the FPR may be the problem. There are tests in the FSM for the FPR, so give those a shot. My initial assessment in the other thread suggesting the fuel filter, was due to your low pressure - a clogged filter will substantially reduce fuel pressure throughout the system, leading to lean mixture and missing.
As to fuel injectors, cleaning, flow-balancing, and spray-patterning fixed an intermittent and annoying idle problem with my SE last year. If you have any spare injectors to swap, that may help diagnose the problem. Not all injectors are created equal, however - so you're looking for Orange Top, 680cc flow, SE-injectors. You can also test injectors with them installed on the car, if you look in the FSM - this requires wiring them to the rail and testing with the fuel pump shunt installed.
Good luck, and reply back when you get a chance to try a few things,
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