M20 will not rev past 3,000rpm

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Re: M20 will not rev past 3,000rpm

Postby ivprodigy » Sat Apr 05, 2014 5:11 am

Yep it did. I'm a little slow
When I read at first it didn't make sense to me where the resistor should go until I took the ms apart and saw how things were wired.
I'll be stopping at a radio shack on Sunday to pick up a few resistors to try and clean up this dang noise
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Re: M20 will not rev past 3,000rpm

Postby Yoshi » Sat Apr 05, 2014 12:45 pm

I just put mine in line with the wire because I didn't want to solder in my MS unit. lol. It worked though!
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Re: M20 will not rev past 3,000rpm

Postby ivprodigy » Sun Apr 06, 2014 9:45 pm

I picked up some resistors and soldered a 10k in like with the other one.
The weather is nice so I was excited about the possibility of taking the car around the block for a test drive.
No such luck.

The car will not start now...

It feels as though it may turn over it doesnt. There is also a strong gasoline odor.
Because of that I just took a short video of the fpr. I'm not sure if the fuel is supposed to stay pressurized after the the ignition is turned, but in my case the pressure is turned off almost immediately (it later builds again but the car will not start).

Any suggestions?

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Re: M20 will not rev past 3,000rpm

Postby Yoshi » Sun Apr 06, 2014 10:30 pm

Yea FPR be dead yo. should stay constant.
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Re: M20 will not rev past 3,000rpm

Postby M20_fever » Sun Apr 06, 2014 10:44 pm

Yep, and should hold pressure for about an hour after shutdown.
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Re: M20 will not rev past 3,000rpm

Postby ivprodigy » Mon Apr 07, 2014 2:15 am

Could something else be the cause?
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Re: M20 will not rev past 3,000rpm

Postby M20_fever » Mon Apr 07, 2014 2:28 am

You can see the pump prime the system when you turn the key to 'on', then pressure bleeds off, then the pump comes back on when you crank. All that is how it should happen, but the bleeding of pressure is not correct. What FPR is that? do you have a stock one to try? I'm with Yoshi that the FPR is not working.
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Re: M20 will not rev past 3,000rpm

Postby ivprodigy » Mon Apr 07, 2014 2:49 am

From what I can tell it's a cheap ebay unit.
I don't have the stock one.
What's weird is that there's a click (sounds like a solenoid - can be heard in the video 3 secs in) right as the pressure builds after which the pressure falls to zero.
Interestingly, TunerStudio didn't register any changes in fuel load (though come to think of it I am not sure that that's what it's supposed to be reading...)
I am very tempted to get this one: http://www.r3vlimited.com/board/showthread.php?t=319041 but I'd really like to avoid it if I could.
Spending another $25 for a replacement ebay unit seems like a simple solution - reliability issues aside.
Damn, this weekend was expensive enough as it is...

Edit - I'll check all the vacuum lines to make sure that I didn't pull something off by mistake...
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Re: M20 will not rev past 3,000rpm

Postby M20_fever » Mon Apr 07, 2014 3:00 am

You can try the FPR test procedure in the Bentley to see if it passes. Why do you need an adjustable FPR right now anyway, your still NA right? Just snag a stock one off of one of the part outs going on right now.
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Re: M20 will not rev past 3,000rpm

Postby ivprodigy » Mon Apr 07, 2014 3:17 am

I dont need one.
It came with the car (it had been turboed in its past) so I figured I'd maintain the status quo by replacing it.
I'll look into getting an oem one as well...
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Re: M20 will not rev past 3,000rpm

Postby Yoshi » Mon Apr 07, 2014 11:45 am

Either the pump isn't working or the FPR is bad. But since it manages to build pressure pretty quickly, I'd guess FPR.
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Re: M20 will not rev past 3,000rpm

Postby ivprodigy » Thu Apr 10, 2014 6:14 am

Well it's close week at work so I haven't had a chance to look at any other causes. Instead I went ahead and ordered a new afpr.
It's a cheap knock off again but it'll bolt up in the same location and I'll be able to tear down the old one to investigate what went wrong...
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Re: M20 will not rev past 3,000rpm

Postby M20_fever » Thu Apr 10, 2014 12:35 pm

Git er dun, registration for the first points event opened already.
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Re: M20 will not rev past 3,000rpm

Postby ivprodigy » Thu Apr 10, 2014 12:47 pm

Yep got the email! May is too soon! I didn't think I'd ever say that
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Re: M20 will not rev past 3,000rpm

Postby ivprodigy » Sat Apr 12, 2014 8:22 pm

I feel like I've taken a step forward yet maybe two steps back.

The afpr came in yesterday so I replaced the old one.
The car started and sputtered along for a bit (running quite rich). I tried revving it again and it was chocking out after about 2k rpm probably because of the excess of fuel...
Pressure held ok but when I tried running it again this is the result.



ps i took the old afpr and it looked like some debris was imbedded in the membrane which was probably the cause for the drop in pressure in my previous issue...

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