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Discussion Starter · #21 ·
So I rented a fuel pressure gauge and hooked it up at lunch. Turned the key to the on position and pressure went to 60psi than dropped to 56psi than proceeded to keep dropping to 46psi within 10 minutes or so...while running it held at 60psi. Appears to be a pump/regulator issue. Fantastic!!
 

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Do you have a tune on it or stock?
 

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Discussion Starter · #23 ·
It currently has a tune on it..I have the tune for 5 years. I was considering reflashing it in hopes something might change, but not holding my breath
 

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I would, had similar issue with mine, had tranny work done last fall and after re-tune it went away, crancked it up middle of winter and did not have that issue.
 
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Testing in the service manual says to turn on the ignition, That will request the fuel pump to run for about 2 seconds an then shut down (since the engine is not detecting any rotational speed). Pressure must be from 55 to 60 psi. After 1 minute of off time, the fuel line pressure must remain within 5 psi of that pump running psi. Any psi decay beyond that point (they say) would indicate that 1 or more fuel injectors are letting fuel pressure leak by it/them.

Normally, a person inserts the key, then rotates it to start the engine right away. If fuel line pressure had decayed a bunch, the fuel pump would take a second or two to bring that line pressure back up to that 60 psi level. That might make for a lousy start sequence. Another test (with everything cold), would be to rotate the ignition key to the on/run position for 2 seconds. Let the fuel pump run an pressurize the fuel line an then turn the ignition key back off. Now rotate the key for a normal start cycle, an monitor how the engine reacts. If it was flooded doing this would probably not help. If it was due to fuel starvation (low psi) then the start event may work just fine in a cold condition.

The in-tank fuel module includes a back flow check valve in the outgoing fuel line. This to prevent the line pressure from being lost when the car is not running for several hours. You "don't want it" to be the bad guy here.
 

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Discussion Starter · #26 ·
It appears I have a little more digging to verify between injectors, pump, or check valve. I’m really hoping it’s the injectors if the reflash doesn’t work. I don’t really want to deal with either the fuel pump/regulator or check valve.
 

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Dont let that fuel pump scare you if you end up having to go that route, not that bad to do going threw the rear seat, dremel is your best friend.
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Since the fuel pump regulator is designed to regulate psi at 55 to 60 psi, an your getting 60 psi, it sure sounds good to me (especially when the engine is running). They say a 2 sec on/off static run test of the pump an regulator that reaches 60 psi, most likely will decay to a stable reading of about 55 to 56 psi shortly after shutdown. Its when it continues to decay, that leaky injector(s) are suspected. Especially since a clear flood procedure was tried an you then got a normal cool start.
 

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Discussion Starter · #29 ·
I’m not so much scared it’s just I’ve been at this for while...just want a break lol

I’ll check the injectors first I saw there being a thread on here I read about loosing the intake bolts lifting up the intake & zip tying plastic baggies under each injector to see which injector was bad. I would try that and see if one or more are leaking. Than most likely at 200K I might just replace all of them...
 

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I would check the ohms first on those injectors, pretty easy to do lots of videos on how too, before you tear everything apart.
 

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A few years ago, made a fuel pump access covering for a relative's vehicle and it turned out pretty good. Covered the hole with a piece of metal, self-tapping screws and high temperature sealant. Along with transmission pan drain plugs, seems like they should be an industry standard. (where applicable).
 
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Discussion Starter · #32 ·
Yea I saw on g8only.com they make a cover plate but hot dog that thing is $165. Some guys at work were saying that when they worked on Japanese cares they all had an access panel designed into the car. Also did a remote start today temp was about 65 and could hear it struggle but not as noticeable because it’s warmer out. First check ohms/resistance at injectors, than proceed from there.
 

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Regarding the intake air temperature spikes, there will be variations especially on initial startup as the engine reaches operating temperature. Eventually, as the engine idles down the readings should level off. Either way, there should be consistency in the line. Large, erratic fluctuations (spikes) could indicate an internal or some other sort of failure.
 
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Discussion Starter · #34 · (Edited)
Might be injector 1...ran an injector balance test with the scanner & it initially failed the test tried to re run after I did clear flood procedure than started the car to clear the fuel than re ran the test & it passed. So I want to re run it again after it’s been sitting for a while. I’m hoping that’s the issue. All other injectors passed first time.

Left the pressure gauge on for 2 hours after lunch and it read 30 psi when I went to remove and leave for the day.

Going to reinstall the gauge tonight and see why reading is in the morning and try the injector test again before I leave for work.
 

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Discussion Starter · #35 ·
Know my thinking is if I prime the system to get fuel pressure up and it still starts out running like dirt than a cylinder(s) are flooded.

But if it runs like a racecar should that the regulator is bad on the fuel pump and the fuel is framing back to the tank.

Does that make sense.
 

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Prime the system as in the clear flood procedure, rotating the ignition key several times to on prior to starting the vehicle, or something else?
 

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Discussion Starter · #37 · (Edited)
Just turn the key to the on position 2-3 times to prime the system. Than try to start it and see how it runs I would think if the injectors were leaking the cylinders would be flooded and the car would sound like dirt & have an issue trying to start.

Not the clear flood procedure.
 

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You get 60 psi, pump appears good. To check is the injectors are leaking. Unbolt the fuel rail and lift it a up with the all in the rail. Turn to the “On” position to build pressure. Don’t start it. See if any injectors leak or drip. If they do leak. Send them out to be cleaned and new filters installed. Good idea to clean the TB and Maf too
 
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Discussion Starter · #39 ·
True but doesn’t the regulator which is part of the pump assembly assist it keeping pressure in the fuel line also.? If that were an issue would it not cause pressure to drop in the line as well.?
 

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Technicality, separating the fuel supply line at the fuel rail, an inserting a fixture with a "shutoff valve" that allows you to reconnect the 2 pipe sections as well as allowing you to isolate the fuel rail portion from the supply line, would be a great test. With that fixture in place as well as a pressure gauge installed at the Scheader/bleed-down fitting at the front of the fuel rail, that would allow you to test the injectors only, for leaks. Pressurize the fuel rail to get that 60 psi value, "close the shutoff valve", an watch the pressure gauge. This isolates the injectors from the rest of the fuel system. If the pressure decays, you know its the injectors. An since all indications show a flooded engine, I'm pretty sure the psi will drop off doing this The bad is not having such a tool handy in your hip pocket. If pressure dropped off going back to the fuel tank, then you would have to suspect the fuel module has a faulty back flow "check valve". But that would set up a fuel starvation type of condition at the next cold start up event, not a flooded engine.
You gotta know that the pump can make all kinds of pressure, as well as supplying all the volume you would ever need. The regulator obviously works as intended, because it keeps all that supply line fuel at the 60 psi value.
 
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