I really think it has something to do with your wide band. You may have other issues that make it misfire too but that looks just like a failing wide band.

 

Check the voltage of the pumps under boost. Had something similar happen to me. he car was fine driving around but at about 24psi it suddenly went lean. Checked the voltage going to the pumps and under boost the voltage dropped to about 10 volts. This also seemed to mess up the pump. I ran a relay straight from the battery. Problem solved. By the way great build.

 

Last night I just hard wired (soldered) both pumps into the factory wiring, running them together off the common factory harness. Although I know that is lame, I ran out of time last night. I don't think it is contributing to the larger problem. But...

At lunch today I added high current spade connectors for easy removal of the assembly and wired the second pump off a dedicated set of wires from the battery, triggered by a relay getting it's signal from the other pump. So now I'll have both pump running all the time with each getting clean powa from their own wiring.

I check the MAF and the honeycomb looks good.

I also dropped the bosst to run off the wastegates 17 psi. We'll see what happens on the drive home.

 

I ended up chasing my tail for a couple of days on a failing WBo2 as well on my old Mazda. If you have a spare sensor, it might be worth dropping that in before you start messing with the tune too much.

Hope you get it figured out!

Dave

 

Updates on lame problem...?

 

i hate cars... I am having a *** load of problems trying to get mine ready for the track. good luck with yours hope you made it.

 

um...didnt u make that on race gas?

and to the OP, this is one of the sicket build threads i have ever seen. props

 

Went to the track.... and watched people. Couldn't resolve the issue in time. I'm starting to believe that the wideband is the issue and that all of this will have been a wild goose chase. The WB is now starting to act up at start-up as well. I had the wiring come loose under the car and drag on the ground a month ago, doing some damage to the connector and wiring - but it worked fine after that. Anyway, going to get a new sensor and see.

But there are more issues.

I hooked up the Full Blown setup with dedicated wiring to give each pump ample voltage. The car will not idle with both pumps on. I modified the return fitting as outlined by Ted B, but it doesn't seem to be doing the trick. The car idles and drives fine on 1 pump but won't on both. I don't have an easy way to monitor fuel pressure either as the factory lines are all fittings and not standard hoses on the high pressure side where the gauge would sneak in. I think I'm going to need a new fuel rail and regulator to make it work.

I'm leaking coolant somewhere - I think it's the fitting at the turbo, which is an easy fix should that really be the location.

And I've got some crazy whinning noise coming from the engine bay. It sounds like a fuel pump in pitch and general noise - but it's not the fuel pump. You can really hear it resonate through the firewall while sitting in the car, and it follows the engine RPMS. It is hardly noticeable outside the car while listening with the hood open. I don't know what it could be. Maybe a bearing going bad in one of the spinning accesories like the alternator, AC, power steering etc. Hopefully it's not the oil pump or something. The sound isn't mechanical enough to be that... I think...

 

I run a VDO fuel pressure sensor.. simple 0-5v item. I run to my AIM dash.

I've heard the stock ECU has some un-needed analog IN's?

I agree with the idea of wanting both pumps on... I always wondered what would happen when a pump craps out on a twin pump setup with pressure switch.

 

lolz if you could make 490/480 on the 30R on pump everybody would run one

c16 is closer to e85 than 93, wasn't comparing apples to apples anyway...

Scorke

 

I've had similar problems that ended up being wideband in the past. Definitely eliminate that as a possibility.

 

Run a pressure switch on the second pump. I use the aem to fire the second pump at 15 psi.

 

i had a "fuel pump sound" coming from the engine bay when i did my timing belt and set the balancer pulley to tight....

 

if you want to run both pumps all the time, which i strongly recommend, then you have to drill the hole in the jetpump (plastic thingy where the return fuel passes) to 3,5mm. Otherwise you wont get your base pressure down.

I have tried it, worked great on the track with 700bhp and E85.

Good luck

 

updates plzzzz