When you turn the key on, the pump only primes it for a second, pump obviously doesn't stay on. It won't hold the pressure with the car off.

Just don't even bother checking fuel pressure without the car running.

Other than that, I don't know. Everything should be fine.

 

Thanks Wes. Only problem is everything isn't fine lol. The car still idles at 100psi without any regulators in the system. This should tell me by Zooomer's explanation that there is a restriction somewhere in my system (return line likely). If there is I certainly don't see anything...

 

Just a thought, sorry to chime in late... but are they talking fuel pressure at the rail or in your line? Where do you have your gauge connected to? It could be the gauge maybe?

Just trying to give you some ideas.

 

Thanks for the idea. Right now I'm taking pressure on the rail's schrader valve fitting. You can also take pressure on the ZZP regulator, however it is out now.

The gauge should be OK, as it worked on two other cars normally.

 

I am in the process of doing this right now I have the walbro but you still need the little plastic block off disc in the stock regulator correct?
sorry for thread jacking

 

Should. That's the 05' weird pump and regulator.. Good luck, mine isn't doing soo good...

 

I just know that when the signal is bad on some of the sending units, the gauges will peg out, it could be the gauge not the kit, assuming that its electrical, i would check your connections for voltage 12v or more.

wow random thought three tvs posting in the same thread lol

 

It's a mechanical gauge connected directly to fuel pressure. Actron model CP7818

TVS POWAAAHHH!

 

OK I did an experiment...

Returned the fuel system back to stock by re-installing the ball and spring into the regulator.. Car idles at 78psi, WTF!!!??? Stock should be 58psi...

 

and you said that with the regulator not hooked up it was 100?

 

Correct.. Something is acting really screwy here... It should be back to the stock pressure of 58psi give or take a little.

 

either a) something wrong with your regulator or b) something with your filter or lines? I know you said there is nothing wrong with your lines?

 

Yes, the filter and lines are OK I just checked them. What's weirder yet, is that I just hooked up the ZZP piece in the option 1 config and it worked.. It idled at 58psi, and I was also able to increase the fuel pressure by blowing into the vacuum line to simulate boost conditions... I was not able to lower FP, as the stock regulator does that.

I think I am going to pull the stock reg back out of the canister for ***** and giggles. I really want to run option 2, so I will try again before I quit...

 

let us know how that goes.

 

So you have 78psi without the ZZP regulator installed and it drops to 58 when you add the ZZP regulator? This makes no sense at all. Adding another regulator can not make the pressure decrease unless it introduced a new path to return fuel to the tank.

 

ya or nay?

 

If your pump isn't keeping up, then a rewire will help.

 

Anddddddddd..... It works!!!

No idea why... I sat the tank under the car with the lines attached and played with it until all of a sudden it worked... I put in the stock reg ball and removed it a couple times and took the ZZP unit off and on several times...

The car sit at 58psi base pressure, and about 50-51psi with the vac line hooked up... Does that sound right? The car pulls about 18psi of vacuum on an Autometer mechanical gauge.

I have the pump rewire as well, so it works, and should give the pump a little bump up top if it needs it...

Thanks Zooomer and Matt for the assistance. Please write better instructions for the next guy lmao. ;-)

 

Car pulls 18 Hg at idle, not PSI. Sounds about right.

 

That's what I meant lol. Gotta cut me a break after inhaling gas fumes for four hours lol...

Glad it's working now though. I just logged my fuel trims on a short ride and they were barely off, so I'll have to try and get my tune worked in fully over the next few days.

Thanks for all the help everyone..!

 

Honestly, 58 base is probably overkill for pump gas. Unless you plan on going E85 soon, you can probably drop that.

 

Is there any hurt to keeping the pressure high?

E85 won't be real soon... So what should I drop it to?

The 80's are spec'd to...

Static Flow Rate: 80 lb/hr at 43.5 psi
Static Flow Rate: 92.38 lb/hr at 58 psi

So I guess I could run 43.5 psi? It would make the tuning easy... 2 voltage multiplier and 40 injector flow rating. Then just copy over the -108KPA values I believe in the IFV vs. Vac. vs Volts or whatever that table is called.

I'm just worred about playing with it again...

 

UNprivate messaging.

 

Pfft, whatever works...

 

Drop it back to where it was when we shipped it.

Remember to flatten out the injector flow chart in the ECM. It doesn't need to be completely flat, but the slope will be much less than it was with a fixed fuel pressure.