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Old 11-17-2010, 01:28 PM   #11
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Does your fuel pass the FSM tests for leakdown? You are mentioning with vacuum unhooked, that sounds like a running test.

FSM has us hook up the FP gauge and then click the key and bleed the system. No starting. After it'* bled, click the key til max pressure readings are taken. What is the pressure? Then let it sit for 10 min, I forget how much bleed down is acceptable, but it'* something like a couple of psi over the 10 min.

If you don't have any pressure holding in the lines, cranking can be extended as the pump comes up to pressure.
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Old 11-17-2010, 01:31 PM   #12
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Does your fuel pass the FSM tests for leakdown? You are mentioning with vacuum unhooked, that sounds like a running test.

FSM has us hook up the FP gauge and then click the key and bleed the system. No starting. After it'* bled, click the key til max pressure readings are taken. What is the pressure? Then let it sit for 10 min, I forget how much bleed down is acceptable, but it'* something like a couple of psi over the 10 min.

If you don't have any pressure holding in the lines, cranking can be extended as the pump comes up to pressure.
What could cause such a problem?
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Old 11-17-2010, 01:35 PM   #13
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FPR or the check valve in the overpriced pump.
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Old 11-17-2010, 01:36 PM   #14
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FPR or the check valve in the overpriced pump.
This happened with the stock pump and the new pump as well. Doubtful that they'd both be bad.

I might try to pull an FPR or two from a junkyard car and see if that makes a difference if this new tune doesn't fix it.
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Old 11-17-2010, 01:40 PM   #15
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If I were there, I'd make you test and find out which part is bad and which isn't. I find many pumps that have bad check valves. Many.

Take a fuel pressure tester and get yourself another piece of pressure rated hose to connect. cut a chunk off a fuel rail (the bigger of the two connections, aka supply) and put that into the hose. Then you can test right before the filter, at the rail before the fpr etc
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Old 11-17-2010, 01:45 PM   #16
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Ok, I'm highly doubting its the pump. I'm going based on which one'* easiest right now. The easiest is to flash the PCM with the 2bar settings to see if that does it. If it doesn't, I'll go from there. The reason for this is that I don't think its the pump. Could it be the pump? Sure. All I know is with the L27 in that engine bay, it fired up in under a second every single time no matter how hot or cold it was. The moment I got this L67 put in, I started having issues cranking. Could that factory pump have gone bad in the 4-5 months during which the swap was taking place? Could both the new pump and the old pump be bad? Sure, but it would be one hell of a coincidence.

I'll let you know what happens when I get the tune back and flashed. I really don't feel like dropping that gas tank again. Its a pain in the ***. I'll have to see what fittings were included in the fuel pressure tester, since the hose that'* attached to the gauge only connects to the rail.
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Old 11-17-2010, 02:39 PM   #17
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Pressure drop can also be a leaking injector. Pulling plugs can show this, the leaking injector will have a much blacker plug.
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Old 11-17-2010, 02:47 PM   #18
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Pressure drop can also be a leaking injector. Pulling plugs can show this, the leaking injector will have a much blacker plug.
I'll pull them tonight to see if that'* causing the problem.

I got the tune back from [email protected] and had that flashed. Can't say I felt much of a difference in cranking times.

Bill, what steps do I need to take to check what and where and how to see where my problem is?
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Old 11-17-2010, 07:49 PM   #19
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Andrie, shoot me the HPT file if you could.

Also, get a fuel pressure gauge on it, have your wife command the key while you look at the gauge.

Have her turn the key on and see if the pressure shoots right up. Also, bleed the pressure back off, and have her start the car and see what the fuel pressure does.

Another thing, try starting the car at like 1/4 throttle and see if that makes a difference. Could be the IAC no responding to its commands quick enough or it could be sticking or bad.
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Old 11-17-2010, 07:53 PM   #20
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Tried starting it again from cold start just now. The first time, it was right after I had flashed the tune. This time, it fired up in under half a second, from a 45 degree engine temp. That'* a first. If it does it again tomorrow morning, I think its safe to assume that the MAP recalibration did the trick.
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