Fuel pressure regulator recommendation
- Thread starter goldNSX
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IMO it really depends on what you are looking to do with it; I replaced mine when I went to the Walbro 255 HP fuel pump, because I didn't know if the stock fpr could handle the flow.
Why are you replacing the stock fpr?
Why are you replacing the stock fpr?
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I suspect to have fuel delivery related problems and may change the FPR and/or fuel pump. Thanks for the hint on the Walbro.
Does the AEM FPR plug and play in the NSX or is there anything else needed? Does it stay in the same place as the old one?
Ok, first things first, just to confirm, you've already replaced the stock fuel filter, right? I would assume the fuel pump would be more suspect than the fpr, but that's my take, might want to ask a few other folks that as well.
I installed the Walbro 255 hp and the AEM 1:1 fpr before I installed my CTSC, but now that I have uninstalled the CTSC I am still running the Walbro and AEM, and the car is running fine.
What year is your NSX? How many miles?
I installed the Walbro 255 hp and the AEM 1:1 fpr before I installed my CTSC, but now that I have uninstalled the CTSC I am still running the Walbro and AEM, and the car is running fine.
What year is your NSX? How many miles?
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It's a 91 with 65k miles. The fuel filter has been changed. My problem is described in thread: http://www.nsxprime.com/forums/showthread.php?t=94278
Thanks for your help.
Np, glad to be of help (this is my favorite bit of NSXPrime). I would recommend in that case following the recommendation and getting another stock FPR.
However, the ignition switch on my Mom's NSX did go out, and the car would just die. I would personally replace that myself just to not have to worry about it (I did on my NSX). The ignition switch is the piece that you place the key into (the back half). The connections get worn down.
However, the ignition switch on my Mom's NSX did go out, and the car would just die. I would personally replace that myself just to not have to worry about it (I did on my NSX). The ignition switch is the piece that you place the key into (the back half). The connections get worn down.
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My car doesn't die while driving but when trying to start the engine and turning the key nothing happens, not even the starter turns. And sometimes even if the starter turns the engine won't start. This problem is quite new.
Ignition switch: Is it this one?
011 35130-SL0-A01 SWITCH, STEERING 1 1991 NSX $60.96 or part no. 11 in http://www.acuraoemparts.com/delray...COMBINATION+SWITCH+(1)&ListAll=All&vinsrch=no
Yeah, I think it's part 11. I don't know if it is your problem (doesn't sound like it is), it's something I replaced on mine, like the main relay, as preventative maintenance. Have you also checked your igniter unit (goes underneath the vacuum tubes over the throttle body.
Just guessing now, but that has gone out on my car, too.
Just guessing now, but that has gone out on my car, too.
Have you put a gauge on the fuel filter so see how much pressure you are getting? It should be between 36-44 psi (normally) and 46-53 psi (with the FPR vacuum hose disconnected).
The manual says, if you disconnect the FPR hose and it does not rise from the normal range to 46-53 psi then you should replace the FPR.
I recently changed my Fuel Pump to a Walbro because my fuel pressure was only 28 psi max and no rise with the FPR vacuum hose disconnected. After replacing the Fuel Pump, i'm at 43 psi and all my problems has been fixed. No more CEL 1 & 2. No more hessitation at 3400 RPM. Pressure rises to 50psi with vacuum hose disconnected.
The manual says, if you disconnect the FPR hose and it does not rise from the normal range to 46-53 psi then you should replace the FPR.
I recently changed my Fuel Pump to a Walbro because my fuel pressure was only 28 psi max and no rise with the FPR vacuum hose disconnected. After replacing the Fuel Pump, i'm at 43 psi and all my problems has been fixed. No more CEL 1 & 2. No more hessitation at 3400 RPM. Pressure rises to 50psi with vacuum hose disconnected.
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No, I didn't measure the fuel pressure yet but may will. The problem of low fuel pressure could be pump or regulator related mainly. I've read that the fuel pump has a valve inside holding fuel pressure up after engine shut-down. This may be defective or the FPR is sending too much fuel back.
Interesting to read
as this problem is similar to mine but I don't get any CEL code.
Question: Does the AEM or other FPR has a vacuum hose plug as the stock one? I don't see any on the internet pictures.
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The AEM does have a vacuum hose plug, as well. For my AEM FPR I have the vacuum hose attached and also a full-time fuel pressure gauge installed, so I can see. My car idles at around 41 psi with the hose connected.
I just installed mine yesterday. AEM adjustable regulator direct NSX fit and a Marshall liquid fuel gauge. The AEM regulator runs around $180 and the Marshall fuel gauge with banjo bolt around $75. The car has been running a tad lean the last couple times on the dyno so I opted to go with the regulator to see if it helps...will find out tomorrow.
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The SM has instructions to measure how much fuel the FPR is sending back. I tried this on my both my NSX and did not get any fuel, so I'm not sure if the directions are correct. You might consider trying this yourself.
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Did you solve your problem with the engine running lean?
Other question: I've seen quite a lot of fuel gauges on Ebay but hesitate to install a $14 part in my car as Ebay has quite a lot of bad stuff and I'm used to rob a bank first to pay some part.
WHAT FUEL PRESSURE GAUGE would you suggest besides the Marshal one? It must be of 100 % quality and accurate.
B&M, got it for only $35 from my local parts store. But it is not liquid filled like the Marshal one's. I personal like the look of the B&M over the Marshal.
Hugh, has a great write up on this:
http://www.nsxprime.com/forums/showthread.php?t=72000
Hugh, has a great write up on this:
http://www.nsxprime.com/forums/showthread.php?t=72000
