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*ka24e*

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Discussion starter · #1 ·
So I went to change my injectors earlier today and was rewarded with about 40psi of gas spraying at me.
The first thing I always do when messing with the fuel system is obviously release pressure so that type of shit don't happen.
Anyways, I just picked up some new injectors and got some fuel line also and replaced all the rubber lines. But after releasing the FP I took off the main feed line that goes into the rail (the one that doesn't go to the FPR) and gas came spraying out like I didn't even release pressure at all?
My first question is, is that normal? And secondly, could that be a symptom of a clogged/blocked FPR (it is connected to vacuum) which would make the engine run really rich?
Thanks guys
 
Discussion starter · #3 ·
240-kid said:
it would do one of 2 things, make is run rich or lean

how'd you release the pressure? (Crank the engine w/ the relay out?)
Click to expand...

Yeah, removed relay and cranked for 5 seconds. As of right now its running super rich, i watched as friend revved it (3.5-4k WOT) and it was nothing but pure black thick smoke.
I've replaced the injectors, plugs, checked o2, swapped in a different FPR and replaced the CTS and there are no fault codes, other than Mode 2 (Air/Fuel Ratio) Only the green light blinks, and from what I've read in the FSM they are supposed to blink together at 2k under no load.
 
#4 ·
thick black smoke, what u running in that thing diesel lol for high boost apps right lol. Ok sorry umm it sounds like maybe your return line is blocked or something, but if you took out the fuel pump relay and started it, and waited for it to die, there is no reason it should have pressure still in it, it should have ran all the fuel pressure out. Did the car start when you turned it over?
 
#5 ·
i think your problem was cranking it, not running it? you need to run it with the relay out to releive pressure, at least in my experience. if your running rich... maybe injector/s is stuck open or something? I dont think it throws fault codes at that
 
Discussion starter · #7 · (Edited)
pa s13 said:
yeah that is what i was getting at, he shouldnt just crank it, it should start and stumble for a little bit, and then die out
Click to expand...
Thats how I've always done it tho:12dunno and have never had that much pressure. The last time I changed injectors i released pressure and pulled 1 injector out of the rail, and gas just dribbled out without very much pressure at all.
I might try swapping another FPR later and see what happens.
 
Discussion starter · #8 ·
Ok, so after an oil change, reset the ignition timing and idle, the car runs amazing but still Mode 2 (air/fuel ratio) is not right and I'm still blowing out a little bit of black/grey smoke at WOT. Oh and something else I found out as well. While I was resetting the timing i heard an exhaust leak from my manifold, so i take the heat shield off to find my manifold is cracked almost all the way around in between cyl 2 and 3! I dont have any exhaust gaskets right now, so i used some exhaust tape (not manifold wrap, but an exhaust sealant tape) and stoped the leak somewhat, but its still leaking.
Would that cause a rich condition? It idles perfect at 750rpm, pulls great, but would a cracked manifold be pulling air in or pushing air out during the intake/compression stroke?
 
#10 ·
The cracks in the exhaust manifold will leak air into the manifold, which will fool the oxygen sensor into seeing a lean condition, which will cause the ecu to richen the mixture to correct it.
There used to be a old hot rodders trick in the early days of oxygen sensors and lean running carbs, where you'd drill 1/8 in hole in the exhaust upstream from the oxygen sensor to fool it into richening the mixture.
 
Discussion starter · #12 ·
tyrodtom said:
The cracks in the exhaust manifold will leak air into the manifold, which will fool the oxygen sensor into seeing a lean condition, which will cause the ecu to richen the mixture to correct it.
There used to be a old hot rodders trick in the early days of oxygen sensors and lean running carbs, where you'd drill 1/8 in hole in the exhaust upstream from the oxygen sensor to fool it into richening the mixture.
Click to expand...

Wow, i never would have thought of that. If I could rep you man I would, +1 :thumbsup
 
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*ka24e*
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