Any benefits from fuel pump resistor?

[George]

Hi guys, anyone has experience with these?

Always thought that running fuel pump always at maximum voltage is ok, since it cools and lubricates with the fuel. However they are there on most toyota wiring diagrams. So I wonder if a fuel pump resistor is that good?

For example would it improve fuel pump service life? Or would it improve fuel consumption a bit? (due to less amount of fuel is heated when pumped through fuel ramp, then less amount of fuel is vaporised).

From my own experience I know parts that seem to be insignificant usually aren't that. For example most ppl throw away intake resonator upon conversion (due to space restrictions or maybe bigger air filter), but when I managed to fit one I definitely felt driveability improvement. So I thought the resistors maybe the same deal, or am I wrong?

[wilbo666]

There are a number of reasons, but most of them are pretty minor in my thoughts

Here is a few I can think of...

1 - Lower pump speed leads to longer pump life (as you have already said)
2 - Lower pump speed means a quieter fuel pump at idle when you may hear it
3 - Less fuel flow at low load conditions leads to less fuel heat (personally I don't see this as a large issue)
4 - Less fuel flow at low load conditions (i.e. idle) places less requirement on the fuel pressure regulator (and fuel lines) to bypass fuel under these conditions - FYI I do not think I've ever heard of this being an issue however


Cheers
Wilbo

[dumbass]

i think the only thing it does is add weight to yr car heheheheh
ive never ever used in one a car that was a conversion

[George]

With its weight it just can't compete with solid rear axles and chrome plated bumpers (like on 99.9% conversions I do).

Still worth to try, thanks Wilbo for the noise thing. If I note significant noise/fuel consumption improvement on my own car I would then install it on all conversions, at least as an option.

[dumbass]

when u do many conversions u start not worrying about it
if i told every customer that i need resistor otherwise i wont do conversion then id get no work
the job is onyl as good as what customer supplies and if u did everything 200% perfect then it would cost the customer a million bucks.
plus 99% of the engine importers dont supply the resistor anyway
u prob only do one conversion a month so its ok but do em every day u quickly run out of resistors
i guess some people are more anal than me heheehe

[TERRA Operative]

The resistor is switched in to slow the pump during idle and cruise to reduce cabin noise and pump wear.

Not having it won't cause problems (other than noise etc) and will make tuning a bit easier (less chance of fluctuating pressures etc).

[George]

dumbass: yes you're right about my rate of conversions, that's my hobby and the way of "free" servicing my own car. So I only do wiring at mate's workshop and his guys do the rest. Since that's more an entartainment for me, I sometimes try to make things different just for fun. When in good mood I can make something 200% perfect for some lucky customer, and if he "disappears" for a year or so that's the big reason to do next conversions 200% perfectly :-)

You're right about the resistors being rare, but I can order brand new one for me for only 30 bucks. Look at the problem from different point, people spend well over $500 for cutting some 3-6 dB of noise, the materials they use increase weight by 30-50 kilos, that's about 2% of typical overall weight.

Terra: thanks! Low noise mentioned once more, and this doubles my personal interest in the problem :-) With the ease of tuning note I'll probably not install it anywhere but in my car

[oldcorollas]

the fuel pressure regulator probably has a faster response to change in pressure than the fuel pump does when it changes speed.

[dumbass]

do u mean the plain resistor type
or the fuel pump ecu with built in resistors
more percentage of the wire ups i do run fuel pump ecu with built in resistor,
these are even harder to find and i have afew 2nd hand ones and some even have the plugs but no one wants to pay 100 bucks or more for them
so i never fit em, if i had collected these resistors i might have had 10 or more by now but i used to throw em out,
ill be selling all my small junk or crap soon on ebay or somewhere soon if i get motivated as im trying to clean garage out
so will hopefully get rid of my toyota junk soon

[George]

I think plain 23080-50030 would be fine enough for me. Mate says he has the second type (ECU+resistors), maybe I will make use of it...or at least use only its body and resistors. Anyway that's a pity my power steering and fuel pump sound louder than engine at idle, I think both types are good for queting up the pump

[George]

p/s conclusion

Installed Pierburg inline pump, cat.# 7.22156.60.0 . Surprisingly, it's not just quiet but dead silent instead. So I will run it always at full voltage and keep in mind the resistor option for "loud" pumps such as walbro etc.