Toyota Supra Forums! Join the Supra forum!

Toyota Supra Forums! Join the Supra forum! (http://www.toyota-supra.info/forums/)
-   MKIII Supra (http://www.toyota-supra.info/forums/mkiii-supra/)
-   -   Fuel pump relay and pressure. (http://www.toyota-supra.info/forums/mkiii-supra/11283-fuel-pump-relay-and-pressure.html)

carfanatic89 04-29-2008 08:16 AM

Fuel pump relay and pressure.
 
I hooked a fuel pressure guage to my supra. I found that when you turn the key to the spot right before you crank it. I get no pressure to the fuel rail. Only when im trying to start it does it have pressure, It picks up the signal voltage from the RPM guage I think. So im thinking bad FPR. Am I right, is that what the FPR controls,the inital pressure before to actually try to crack the vehicle. Also no matter if my vacuum lines are hooked or not to the fuel pressure regulator, the fuel pressure stays the same 20 psi down to 15 psi at full throttle way under the 32 to 40 its suppost to be at, but when I turn the car off the rail retains that 20 psi for about 2 hours so I know the fuel pressure regulator isn't stuck. What do yall think it is. Im driving her 300 miles back home i'd like to fix it before I leave. Im putting on a fuel filter 2morrow and testing pressure.

btwilson86 04-29-2008 10:30 PM

From what I read on a post a while back, someone (I believe it was mr. nickleye but I may be wrong) had said that the fuel pump on our cars doesn't start pumping until the engine cranks, as opposed to many vehicles that start when the key is in the "on" position.

cre 04-30-2008 12:25 AM

UGH... p a r a g r a p h s

If I can't read it easily, I'm not reading it.

The fuel pump does not use a priming system (well, mine does, but that's another story). The GE and GTE use different systems, but they both essentially require the engine be moving.

The FPR and FPD maintain a base rest pressure that's used for the initial cranking. If you're using an AFPR and trying to adjust the rest pressure take a look at the FPD it's probably dumping what you're trying to hold.

What else did I miss?

supramacist 04-30-2008 01:21 AM

Didn't you want to say something about paragraphs???

They don't work with that stethiscope do they.

However...., a wooden broom handle could tear something up.

I'm sorry guys. I'm just proud to be a part of this number.

carfanatic89 04-30-2008 06:40 PM

Sorry about the non-paragraphs. I failed english class lol.

Tried to do the simple fuel filter change and I cant get the damn thing off, its driving me crazy. Im going to try again, but the lines are not comming off and im bending the filter bracket.

I also noticed that the fuel line comming off the tank has a small twist in it, Im thinking thats where my fuel pressure is going. Whats the easiest way to fix that, I dont want to replace that whole assembly holding the fuel pump.

Ill listen to the regulator, but what is it suppost to sound like?

cre 04-30-2008 07:35 PM

Heh, if the line's got a kink in it the odds are someone's either already tried to replace the filter or has tried. The best bet is to soak everything down with a good penetrating oil (NOT WD-40!) such as PB Blaster, wait and soak it again. I highly recommend you use line wrenches so you don't round off the hose fittings.

As for dealing with the crimped segment, you've got a couple options. You could either replace it or cut it and add a hose with a new fitting... I'd get a second opinion on that, I've never had to deal with it, but I can't imagine it causing any problems as long as you use actual fuel line for EFI systems and everything's well clamped.


EDIT: I missed the stethoscope remark... a stethoscope for fueling problems? The only thing you'd really be able to tell is if fuel's moving through the system or not. It wouldn't give you any indication of how much or where it's going. I think it was mentioned in this by mistake.

supramacist 04-30-2008 07:45 PM

My thoughts??? anyone? anyone?

Replace all that noise. Pb blast those nuts every time you think about it for a couple of days. I have soaked parts covered in rust and all kinds of muck.

After a few days. The pb blaster allows all of that mess to nearly wipe away clean.

Replace the entire bracket. Pull the tank if if you have'nt. It's the only way you can get the appropriate angles to work without twisting everything to hell and back.

While you're at it order a new walbro and stop working at your car and start working on it.

carfanatic89 05-01-2008 06:39 AM

lol yeah I agree PB is some Bad A** S*** ill try it, it should work. You know what funny, I spent alot if time replacing the gas tank fuel pump, FPR and wires to the fuel pump and relay, think I forgot to replace the filter. mabye thats why they have a "notes" section in the manual.

so your saying that I should drop the tank and get a new fuel pump bracket and get that fuel pump. I heard its BA, gotta save some $$$$ for that.

Im Working on a tight budget, going to college and working at a gas station, enought said lol. everybody I know loves my car but I know it has much more potencial. Cant wait to graduate and put in a 2jz-gte twin turbo.

supramacist 05-01-2008 06:39 PM

If you have reworked it as of late..., no.

But those lines you have kinked up. They all but have to be.

And...., it's much easier to drop the pain in the ass tank but if you undo the top and use a small jack and 2x4 you can lower it out and drag it out quite easily.

It's about an hour round trip. Maybe 2 your 1st time.

The walbro's are 100 bucks. I'm thinking fuel pressure regulator for mine. But I think it's doing alright without one.
A short time will tell.


All times are GMT. The time now is 05:04 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87