I just got my car running after doing a fully built long block and t4 35r setup. Also did a dual intank pump setup from buschur. I have 3 problems:

1. My car is throwing all kinds of weird codes. barometric pressure sensor, fuel pump relay, speed sensor, o2 sensor, etc... I clear them and some come back, some dont, then they come back later. I have a perrin o2 simulator so unless the front o2 is bad IDK whats up with That. Everything is plugged in too.

2. I have a dual intank pump setup from buschur. The 1st pump is supposed to work as normal. 2nd pump is supposed to come on at 6 psi. Last night when were first starting the car the 1st pump was coming on but pumping NO FUEL to through the lines. I pressure tested the 2nd pump by shooting air through the vacuum line to the switch and the 2nd pump turned on and shot fuel out of the line (which was disconnected at this time) We then re connected the lines and used the 2nd pump to build pressure through the lines. We then tried to start it again and it fired right up. Only thing is now when i drive the car, the car sometimes will jsut go super lean. This is at 0 boost, maybe 20% throttle, like leaving from a stop light, the AFR's go past 18:1 and the car stutters like it has NO GAS. But this is no consistent because 3 out of 4 times its fine. I can also partial throttle it up to about 15 psi and the afr's will stay in the 10's and 11's. Car has a 35r, stock ecu, stock flash, stock mas, stock injectors. I'm waiting to do anything else until I know it runs right.

I just got the car running at midnght last night so I have to play with it more after work. I'm trying to avoid pulling the fuel pump setup but I see that in the near future. if anyone has any ideas of what it could be off the top of their head i'm open to suggestions.

-Steve





PS: the mass air flow has no filter on it and is missing some clamps. I'm putting aem in the car but i just wanted to get it running and make sure everything is ok first.

 

wow thats alot of codes.

I had a similiar problem after a Zeitronix install, ended up being a loose cable on the ECU. I would hunt around for some loose connections that may be causing the grimlins in your system.

Good luck.

 

Have you calbrated the MAF in Ecuflash?

Your using a hob switch for the 2nd pump correct? but you said neither pump is flowing any fuel?

I kept having fuel leaks with the rubber lines and inline filter..

I had to convert mine to prolite -6 an lines, and use a -6 an earl fuel filter.. which fixed all of my issues.


After rereading, it seems like your fuel pump isnt flowing any fuel. Check wiring.

 

no leaks found yet, the 2nd pump pumps perfect, i believe the problem to be with the first pump

 

just rewire the 2nd pump to pump all the time, then see what happens

 

hmmm just to see what happens right? where in the engine bay can I get ignition power from? I have the wire already in the engine bay going to the pressure switch so it would be nice if I could just bypass the switch for now and see how it is like that but I cant connect it directly to the battery because then it would be on all the time

 

i'm just gonna buy an aeromotive regulator ansd run both pumps simultaneously, but i still need to fix the problem

 

I dont understand what the problem is

I have used many Buschur double pumpers in the past - they are very simple and should not require much tuning - they just run richer on the top end

It seems that you have just have need of additional mapping the the lean areas or a miss fire condition

Best way to diagnose a fuel delivery condition it is with a fuel pressure gauge to watch what the fuel pressure is in the line as you are driving

 

That's is weird, should be fine, double check everything, which I know you already said !

 

The problem seemed to be very low fuel pressure from the primary pump and I verified it today.

I installed an aeromotive regulator with a gauge today. At idle WITH the vacuum line removed from the regulator the fuel pressure is only 22 psi. It should be 43.5. I tried raising it with the regulator and turned it all the way up and it will not go any higher. I added 30 psi of pressure to the second pump pressure switch and that raised the fuel pressure to about 55-60 psi. Again this is all without the vacuum line on. So I'm assuming there is a problem with my 1st primary pump?

AND AL, have you installed a double pumper into a tank yourself??? Does it kinda hit the shroud metal plate thing in the tank a little bit? Did you have to kinda push it down? I'l post pics and vids of what i mean later

 

anyone?

 

bad fuel pump..

 

i have had a couple 255's go bad on me over the years would not doubt it if that is your only problem.... also if your car goes way lean or is running bad it can trip plenty of cels fix the pump & i bet it fixes your engine lights

 

the current code being thrown is po300 and i guess the pump could be bad but its kinda weird since its brand new

 

Sometimes, the one way check valve in the secondary pump can fail and leak some fuel back into the tank when the secondary pump is not operational

Thye double pumper is a tighter fit than the stock unit but it works

Al