I get 40 psi too, and I had the stock fuel pump in, Ill have to check what it is now with my walbro.


How are your pumps so loud, someone mentioned the nickname whinebro? Ive had 5 walbros across 4 different evos and never heard one whine like described..

 

Why does everyone have problems with fuel pressure?

It's so simple.
Measure the pressure before you change the pump.
Measure it afterwards.
When it's goes up (it always does).......you've done it wrong.

Ricer no 1............mine's the same
Ricer no 2 ...............mine's the same
Ricer no 3 ......................mine's the same too.

So it's OK then?

The manual says 33PSI idling.
40 PSI isn't 33 PSI.

Once you get the pressure right, it's right and fixes other problems.
No half arsed software patches required.

 

hmm...but why does it take the car to reach operating temp for it to read .7? when the car was cold it read .8 and stayed there. I have a tactrix cable and evo scan on the computer but dont know my way around it much. I said **** it and did a pull tonight 2 - 4 gear and afr was 11.2 - 11.3. It was at night so temps were cooler. Pump hasnt made the noise again. I think it really has to do with temp because when it did it the temp was around 90 and it was around mid day.

fred - when the pressure goes up you did what wrong? install the pump wrong? i bought the car with a walbro so couldnt check it with stock pump. I dont think you can really **** up changing the pump its straight forward.

 

Resistors change value at different temperatures. Your test shows the resistor is out of spec. I am just a little concerned that your meter might not be calibrated, I wouldnt want you replacing something you didnt need to, which is why i was suggesting trying a different meter. You could even unbolt it and take it somewhere if you dont have access to another meter.

as far as logging you will want to use evoscan to see what your long term fuel trim mid and low are doing

 

it looks like to unbolt it you have to remove the whole bracket with all sensors...i dont mind unbolting it but where can i take it? a regular automotive shop? some type of electrical store?

 

well if its bad you have to unbolt it anyway. Almost any place that does electronics / automotive repair will have a meter. I wouldn't even think a dealer would charge you to test it real quick if your brought it into them. Its like a 30 second thing to throw a meter on it.

 

yeah...I've been searching around for these things...it seems like it's hard to find...I assume it's a rare occurrence for one of these to go bad huh...the only option I got left it's to check the dealer if trying a good meter still gives me the same results...

 

Ok so i just got home and it's hot over here...was in bumper to bumper traffic...I was merging onto a road and cars were coming so I had to get on it in 2nd..after that in traffic the car started idling lean from 15.7 - 16.8 all over...car drove fine but it was doing this...I get home and right away popped the hood and check fuel pressure with vacuum hose and without...also took a pic of what the pressure did when I shut the car off...dropped to 30 ish and stayed there...

1st picture is with vacuum line on - right under 40psi
2nd picture is with vacuum hose off and my finger over it - needle between 40 and 50 psi
3rd picture is after shutting off the car - dropped to right on top of 30 and stayed there
4th picture shows how my vacuum lines are routed just in case there's something wrong

no I did not paint my nails in my 2nd pic that's my wife taking the pic while I hold the vacuum hose...lmk what you guys think...

 

 

there are the steps to trouble shoot fuel pressure issues. You saying the pressure drops when you shut the car off does conflict with what those pages say. Shouldn't drop for a couple minutes. So i would try following the steps and see what you turn up.

 

holy ****..but see, when i shut the car off it dropped to 30 psi but stayed there...

 

Troubleshooting can be a pain in the ***. It can get to a point where its really about how far you are willing to go to track down a problem, and evaluating how big of a problem you really have. Your WOT Afr's are good, your fuel pressure looks good, your resistor is maybe just barely out of spec. The only manifestation of a problem that you have is a reading on your Wideband during idle/cruise, the cars actual behavior you said is fine. Walbro's are known to be noisy, some people never hear them, some do. I notice mine tends to whine after long drives in hot weather, which i think you said was also when you noticed it. So is this a problem you can live with unless it gets worse? If not then you just have to keep eliminating the next most likely thing until you find the solution.

 

i can live with it but what i cant live with is the fact that i know in the back of my mind something is wrong...it keeps poking at me...when the car goes lean at idle you can hear the idle change and its no longer smooth it sound a bit more loby like if it wants to stumble so i know its not the wideband sensor...what worries me about the fuel pressure is that after turning off the car it dropped to 30 and stayed there when observing it before while the lean issue is not happening it stays right under 40 so something is not right...also i noticed that the lean idle issue starts after i get on it...

 

Im the same way, if i know something is wrong, no matter how small, it will drive me crazy. So with the fuel pressure thing, follow the steps from the FSM that i linked and it should help you isolate the culprit.

 

ill get on it and see what i find...thx man...