So I replaced my fuel pump and...

[davidf]

I'm the worlds worst about fix it before it breaks person. Over the years I've replaced numerous items due to age/mileage, needed or not. Last week I had my fuel pump replaced {new OEM} though I was having no issues. In my mind it was time. I can't believe the difference in performance change. The car has always had the slightest of hesitation when cold but was ignored because it stopped after a few blocks. Now, completely gone:wink:. The car has always ran decent up to redline but now it's completely different. The car has never pulled so hard since I've owned it. I guess the motto here is, after 20 years you can lose a couple pounds fuel psi and not realize the performance it can cost you. It's like a new car again.:biggrin:

 

[BTL3.0]

D u have to drop the tank to do the job?

 

[davidf]

Yes.

 

[rollie]

How long did it take you?

or should I say how much time in labour am I expecting to fork out?

Is there anything else we should change while doing the fuelpump?

 

[RYU]

Nice work David! Might I also recommend an injector douche from RC. They give you some pretty neat documentation on flow rates before and after the douche. http://www.rceng.com/Fuel-Injector-Cleaning-P43C0.aspx

All 6 of mine are with them as we speak.

 

[davidf]

Nice work David! Might I also recommend an injector douche from RC. They give you some pretty neat documentation on flow rates before and after the douche. http://www.rceng.com/Fuel-Injector-Cleaning-P43C0.aspx

All 6 of mine are with them as we speak.

I'm seriously considering that also. The car is so crisp now. I believe getting them flow tested and cleaned would poss. boost economy/perf. as well.

 

[davidf]

How long did it take you?

or should I say how much time in labour am I expecting to fork out?

Is there anything else we should change while doing the fuelpump?

I had a NSX tech in Houston do the work. I believe it's about a 4 hour job. Normally I do most of my work but the lift at work has been tied up lately.

 

[enkrypt3d]

I had a NSX tech in Houston do the work. I believe it's about a 4 hour job. Normally I do most of my work but the lift at work has been tied up lately.

how much was the labor & parts? my car kind of stutters when its cold around 2k-3k when it warms up... never understood why......maybe this is it?

 

[mr_goat]

how much was the labor & parts? my car kind of stutters when its cold around 2k-3k when it warms up... never understood why......maybe this is it?

Maybe. Are you getting any CELs? But there are many reasons for this symtom. Bypass your fuel pump resistor first and see if that helps. If it do then it's probably the fuel pump but could be a clogged fuel filter also. So if you haven't changed the filter according to schedule, then do it to while your at it. If it doesn't help, unplug your O2-sensors. If that solves the problem, change them. If it doesn't, check your ignition coil packs for rust, and spark plugs.

A new OEM pump is expensive:

<table border="0" cellpadding="0" cellspacing="0" width="780"><tbody><tr bgcolor="#F4F4F4"><td align="left" height="2" width="8%"> 026</td> <td align="left" height="2" width="13%">17040-SL0-A30 </td> <td height="2" width="30%">PUMP SET, FUEL</td> <td align="center" height="2" width="7%">001</td> <td align="center" height="2" width="6%">1991</td> <td align="left" height="2" width="7%">NSX</td> <td align="right" height="2" width="6%">406.22</td> <td align="right" height="2" width="6%">304.67</td> <td align="right" height="2" valign="middle" width="20%">
</td></tr></tbody></table>
Get the Walbro instead, cheaper and capable of a higher flow rate:

http://www.scienceofspeed.com/products/engine_performance_products/NSX/Walbro/

Davidf: Im really looking forward for my fuel pump change now! =) Did you change the filter to or is it fresh?

 

[enkrypt3d]

Maybe. Are you getting any CELs? But there are many reasons for this symtom. Bypass your fuel pump resistor first and see if that helps. If it do then it's probably the fuel pump but could be a clogged fuel filter also. So if you haven't changed the filter according to schedule, then do it to while your at it. If it doesn't help, unplug your O2-sensors. If that solves the problem, change them. If it doesn't, check your ignition coil packs for rust, and spark plugs.

A new OEM pump is expensive:

<table border="0" cellpadding="0" cellspacing="0" width="780"><tbody><tr bgcolor="#F4F4F4"><td align="left" height="2" width="8%"> 026</td> <td align="left" height="2" width="13%">17040-SL0-A30 </td> <td height="2" width="30%">PUMP SET, FUEL</td> <td align="center" height="2" width="7%">001</td> <td align="center" height="2" width="6%">1991</td> <td align="left" height="2" width="7%">NSX</td> <td align="right" height="2" width="6%">406.22</td> <td align="right" height="2" width="6%">304.67</td> <td align="right" height="2" valign="middle" width="20%">
</td></tr></tbody></table>
Get the Walbro instead, cheaper and capable of a higher flow rate:

http://www.scienceofspeed.com/products/engine_performance_products/NSX/Walbro/

Davidf: Im really looking forward for my fuel pump change now! =) Did you change the filter to or is it fresh?

Thx for the info! My tb, water pump, coils, spark plugs, o2 sensors , cats and fuel filter was changed about 30k miles ago.. inujectors were cleaned and balanced as well. Fuel pump is next.

 

[mr_goat]

how much was the labor & parts? my car kind of stutters when its cold around 2k-3k when it warms up... never understood why......maybe this is it?

Thx for the info! My tb, water pump, coils, spark plugs, o2 sensors , cats and fuel filter was changed about 30k miles ago.. inujectors were cleaned and balanced as well. Fuel pump is next.

Did the problem exist both before and after that service or has i gradually gotten worse since?

I would change the fuel pump anyhow, can't get worse. Are cars ARE getting old, some pushing 20 years. Stuff breaks, even on an NSX. I'm changing my fuel hoses aswell while the tank is dropped, fires are really undesirable.

 

[davidf]

My fuel filter is'nt very old so I left it. An OEM may sound pricey, but it lasted 20 years and was still working. One big issue that bothered me was now we have 10% ethenol in our gasoline here. Ethenol is hard on orings/rubber parts after awhile. Since ethenol was introduced here we've replace many fuel pumps in our Crown Vic cruisers @$350.00. This made me think about the NSX. My tech charged me $175.00 to R&R which is quite fair. I always thought the car ran good less the slight hesitation but now I'm very happy to get in it. Just a couple LBS of lacking fuel pressure makes a huge difference in fuel injected cars. Now I wish I'd done a before and after pressure test.

 

[davidf]

FWIW I did change the pump resistor awhile back hoping to resolve the hesitation but had no luck.

 

[enkrypt3d]

Did the problem exist both before and after that service or has i gradually gotten worse since?

I would change the fuel pump anyhow, can't get worse. Are cars ARE getting old, some pushing 20 years. Stuff breaks, even on an NSX. I'm changing my fuel hoses aswell while the tank is dropped, fires are really undesirable.

Where can I get fuel lines? OEM? Also is the higher fuel rate going to lower my MPG? My car is a daily driver and I need all the MPG i can get....

After I had all that work done the car ran like a champ... but now its showing its age and it just hit 100k miles... So I'm guessing the next part is replacing the fuel pump... I'm hoping the aftermarket one doesn't suck gas like theres no tomorrow....

My fuel filter is'nt very old so I left it. An OEM may sound pricey, but it lasted 20 years and was still working. One big issue that bothered me was now we have 10% ethenol in our gasoline here. Ethenol is hard on orings/rubber parts after awhile. Since ethenol was introduced here we've replace many fuel pumps in our Crown Vic cruisers @$350.00. This made me think about the NSX. My tech charged me $175.00 to R&R which is quite fair. I always thought the car ran good less the slight hesitation but now I'm very happy to get in it. Just a couple LBS of lacking fuel pressure makes a huge difference in fuel injected cars. Now I wish I'd done a before and after pressure test.

Thats not a bad price! ..... hmm

 

[4AU4LIFE]

A new OEM pump is expensive:

<table border="0" cellpadding="0" cellspacing="0" width="780"><tbody><tr bgcolor="#F4F4F4"><td align="left" height="2" width="8%"> 026</td> <td align="left" height="2" width="13%">17040-SL0-A30 </td> <td height="2" width="30%">PUMP SET, FUEL</td> <td align="center" height="2" width="7%">001</td> <td align="center" height="2" width="6%">1991</td> <td align="left" height="2" width="7%">NSX</td> <td align="right" height="2" width="6%">406.22</td> <td align="right" height="2" width="6%">304.67</td> <td align="right" height="2" valign="middle" width="20%">
</td></tr></tbody></table>
Get the Walbro instead, cheaper and capable of a higher flow rate:

http://www.scienceofspeed.com/products/engine_performance_products/NSX/Walbro/

Davidf: Im really looking forward for my fuel pump change now! =) Did you change the filter to or is it fresh?

That ain't expensive. I priced out one today for a 2000 Ranger 2.5L 4 cy reg-cab and it was $642 !!!

 

[mr_goat]

Where can I get fuel lines? OEM? Also is the higher fuel rate going to lower my MPG? My car is a daily driver and I need all the MPG i can get....

After I had all that work done the car ran like a champ... but now its showing its age and it just hit 100k miles... So I'm guessing the next part is replacing the fuel pump... I'm hoping the aftermarket one doesn't suck gas like theres no tomorrow....



Thats not a bad price! ..... hmm

OEM fuel lines. Get them from Acura or Mark at Dali. I've found these for my 91:

This one goes from the filter to the front fuel rail
<table border="0" cellpadding="0" cellspacing="0" width="780"><tbody><tr bgcolor="#F4F4F4"> <td align="left" height="2" width="8%">008</td> <td align="left" height="2" width="13%">16722-PR7-A03 </td> <td height="2" width="30%">HOSE C, FUEL FEED</td> <td align="center" height="2" width="7%">001</td> <td align="center" height="2" width="6%">1991</td> <td align="left" height="2" width="7%">NSX</td> <td align="right" height="2" width="6%">143.00</td> <td align="right" height="2" width="6%">107.25</td> <td align="right" height="2" valign="middle" width="20%">
</td></tr></tbody></table>
This one goes from the front fuel rail to the rear fuel rail
<table border="0" cellpadding="0" cellspacing="0" width="780"><tbody><tr><td align="left" height="2" width="8%">009</td> <td align="left" height="2" width="13%">16723-PR7-A02 </td> <td height="2" width="30%">HOSE D, FUEL FEED</td> <td align="center" height="2" width="7%">001</td> <td align="center" height="2" width="6%">1991</td> <td align="left" height="2" width="7%">NSX</td> <td align="right" height="2" width="6%">86.73</td> <td align="right" height="2" width="6%">65.05</td> <td align="right" height="2" valign="middle" width="20%">
</td></tr></tbody></table>
This expensive one goes from the tank to the filter
<table border="0" cellpadding="0" cellspacing="0" width="780"> <tbody><tr><td align="left" height="2" width="8%"> 025</td> <td align="left" height="2" width="13%">17707-SL0-A31 </td> <td height="2" width="30%">HOSE, FUEL JOINT</td> <td align="center" height="2" width="7%">001</td> <td align="center" height="2" width="6%">1991</td> <td align="left" height="2" width="7%">NSX</td> <td align="right" height="2" width="6%">251.98</td> <td align="right" height="2" width="6%">188.99</td> <td align="right" height="2" valign="middle" width="20%">
</td></tr></tbody></table>
This one is the return hose from the FPR to the tank
<table border="0" cellpadding="0" cellspacing="0" width="760"><tbody><tr><td height="2" width="14%">17723-SL0-931</td><td width="7%">
</td> <td height="2" width="31%">HOSE, PRESSURE REGULATOR RETURN (280MM)</td> <td align="center" height="2" width="6%">91 - 05</td> <td height="2" width="10%">NSX</td> <td align="right" height="2" width="6%">72.20</td> <td align="right" height="2" width="6%">54.15</td> <td align="right" height="2" width="20%">
</td></tr></tbody></table>
The two first are most critical since they are exposed to heat and vibration. I would at least change those, and the return hose. The expensive one requires the tank to be dropped (I think) so I will do that one to when doing my fuel pump.

Your MPG will not be affected by replacing fuel pump or bypassing the fuel pump resistor. The fuel pressure is regulated by the fuel pressure regulator. If your car is running lean at the moment due to bad fuel pump, then your MPG would rise a little with a fresh pump installed, both you don't want to run lean.

That ain't expensive. I priced out one today for a 2000 Ranger 2.5L 4 cy reg-cab and it was $642 !!!

Yes it is, compared to the wally which is $123 fron SOS =)

 

[enkrypt3d]

OEM fuel lines. Get them from Acura or Mark at Dali. I've found these for my 91:

This one goes from the filter to the front fuel rail
<table border="0" cellpadding="0" cellspacing="0" width="780"><tbody><tr bgcolor="#F4F4F4"> <td align="left" height="2" width="8%">008</td> <td align="left" height="2" width="13%">16722-PR7-A03 </td> <td height="2" width="30%">HOSE C, FUEL FEED</td> <td align="center" height="2" width="7%">001</td> <td align="center" height="2" width="6%">1991</td> <td align="left" height="2" width="7%">NSX</td> <td align="right" height="2" width="6%">143.00</td> <td align="right" height="2" width="6%">107.25</td> <td align="right" height="2" valign="middle" width="20%">
</td></tr></tbody></table>
This one goes from the front fuel rail to the rear fuel rail
<table border="0" cellpadding="0" cellspacing="0" width="780"><tbody><tr><td align="left" height="2" width="8%">009</td> <td align="left" height="2" width="13%">16723-PR7-A02 </td> <td height="2" width="30%">HOSE D, FUEL FEED</td> <td align="center" height="2" width="7%">001</td> <td align="center" height="2" width="6%">1991</td> <td align="left" height="2" width="7%">NSX</td> <td align="right" height="2" width="6%">86.73</td> <td align="right" height="2" width="6%">65.05</td> <td align="right" height="2" valign="middle" width="20%">
</td></tr></tbody></table>
This expensive one goes from the tank to the filter
<table border="0" cellpadding="0" cellspacing="0" width="780"> <tbody><tr><td align="left" height="2" width="8%"> 025</td> <td align="left" height="2" width="13%">17707-SL0-A31 </td> <td height="2" width="30%">HOSE, FUEL JOINT</td> <td align="center" height="2" width="7%">001</td> <td align="center" height="2" width="6%">1991</td> <td align="left" height="2" width="7%">NSX</td> <td align="right" height="2" width="6%">251.98</td> <td align="right" height="2" width="6%">188.99</td> <td align="right" height="2" valign="middle" width="20%">
</td></tr></tbody></table>
This one is the return hose from the FPR to the tank
<table border="0" cellpadding="0" cellspacing="0" width="760"><tbody><tr><td height="2" width="14%">17723-SL0-931</td><td width="7%">
</td> <td height="2" width="31%">HOSE, PRESSURE REGULATOR RETURN (280MM)</td> <td align="center" height="2" width="6%">91 - 05</td> <td height="2" width="10%">NSX</td> <td align="right" height="2" width="6%">72.20</td> <td align="right" height="2" width="6%">54.15</td> <td align="right" height="2" width="20%">
</td></tr></tbody></table>
The two first are most critical since they are exposed to heat and vibration. I would at least change those, and the return hose. The expensive one requires the tank to be dropped (I think) so I will do that one to when doing my fuel pump.

Your MPG will not be affected by replacing fuel pump or bypassing the fuel pump resistor. The fuel pressure is regulated by the fuel pressure regulator. If your car is running lean at the moment due to bad fuel pump, then your MPG would rise a little with a fresh pump installed, both you don't want to run lean.



Yes it is, compared to the wally which is $123 fron SOS =)

So $537 in parts for all lines and the wally fuel pump + labor...hrm.... Might as well do it all at once right?

 

[mr_goat]

So $537 in parts for all lines and the wally fuel pump + labor...hrm.... Might as well do it all at once right?

Don't forget the crush washers for the lines to. Don't remember how many you need but if you order these you all good:

16 of these
<table border="0" cellpadding="0" cellspacing="0" width="760"><tbody><tr><td height="2" width="14%">90428-PD6-003</td><td width="7%">
</td> <td height="2" width="31%">WASHER, SEALING (12MM)</td> <td align="center" height="2" width="6%">91 - 05</td> <td height="2" width="10%">NSX</td> <td align="right" height="2" width="6%">2.88</td> <td align="right" height="2" width="6%">2.16</td> <td align="right" height="2" width="20%">
</td></tr></tbody></table>
1 of this for the service bolt on the filter (comes with new filter together with four of the above type)
<table border="0" cellpadding="0" cellspacing="0" width="780"><tbody><tr><td align="left" height="2" width="8%">018</td> <td align="left" height="2" width="13%">90430-PD6-003 </td> <td height="2" width="30%">WASHER, SEALING (6MM)</td> <td align="center" height="2" width="7%">001</td> <td align="center" height="2" width="6%">1991</td> <td align="left" height="2" width="7%">NSX</td> <td align="right" height="2" width="6%">2.28</td> <td align="right" height="2" width="6%">1.71</td> <td align="right" height="2" valign="middle" width="20%">
</td></tr></tbody></table>
Important! all parts listed are for a 91 coupe with manual tranny, don't know the differences for the other models/years.

Supply the labor yourself and save the money.

While I am at my fuel supply systems, I'll get my injectors reconditioned and replace all o-rings/gaskets for them. And the o-ring for the fuel pressure regulator also.

 

[mr_goat]

By the way, this is what the service manual says about the fuel hoses (1991):

"The rubber fuel hoses need periodic replacement since they are subject to cracks and deterioration during a long period of use"

Manual says change interval for filter and hoses every 60k miles or every four years.

 

[RYU]

That's very useful info Mr. Goat! Much appreciated.

David, I just got my injector flow report back and i'm a happy camper :biggrin:

 

[davidf]

^^^^^^^Turn around time was?

 

[enkrypt3d]

^^^^^^^Turn around time was?

For me it was about 2-3 days since they are local if i remember correctly...

Now I'm definitely going to get the fuel pump & lines replaced ASAP.. Its probably never been done and I've had the car for 4.5 years........

 

[RYU]

^^^^^^^Turn around time was?

They do a lot of mail orders. Typical turn around time is 24hrs.

I'm excited to work on the pump but I need to figure out which pump to get and order the fuel lines. It's going to be a big job...

btw.. I only have jackstands in my house. Do you know if I need a lift to be able to slide out the tank from under there?

 

[davidf]

Any of you doing the R&R fuel pump may want to do a before/after psi test to see what you've gained. I really wished I had.:frown:

 

[davidf]

They do a lot of mail orders. Typical turn around time is 24hrs.

I'm excited to work on the pump but I need to figure out which pump to get and order the fuel lines. It's going to be a big job...

btw.. I only have jackstands in my house. Do you know if I need a lift to be able to slide out the tank from under there?

My tech did it in his garage so I assume yes it will slide out.