New Rebuild Won't Start, Fuel Issue?
 

So, the background of the car is this, I picked it up from Speed 1 on Saturday. They did a rebuild with street port on a single turbo 3mm motor. While they were in there I had them install a new fuel system, (850 primaries, 1600 secondaries, KG rails, and AEM FPR), they also did a fuel pump rewire on a 20b pump.

The last time the car ran was pulling it on the trailer at Speed 1, it was probably very low on gas at this point. When I got it home it wouldn't start and I just assumed out of gas. I have since added gas and checked grounds, spark, and so on. After doing this and cranking it to the point I thought I would've flooded it I pulled the plugs and they were dry.

My only though is that something in the fuel system is not allowing fuel into the motor. I say this because after cranking the FPR gives off a loud buzzing for about 30sec and then it sounds like a bubling noise. Gauge on FPR reads about 25 This is my first time dealing with an aftermarket fuel system so I am lost. Also dave accidently set the PFC for 725 primaries, I plan to change this once running again.

Long post but help is very much appreciated, I need this running by friday at the latest so I can get it to where I get it "inspected".

Thanks,
Ryan

No thoughts on this guys? I really need to get it running today. My only thoughts are FPR, bad injectors/wiring, or air in the lines. And I dont know how to check for any of those.

Throw a fresh set of leading plugs on. You most likely flooded the engine, a new engine is VERY prone to flooding, and if you started it quick to move it on a trailer then shut it down it's very likely flooded.

Plugs can "look" fine but not work worth a damn, I've verified that first hand.

Start with the easy stuff first.

Dale

I will pick up a set of plugs on the way home from work and try that.

To ensure that I am getting the right ones, part numbers are BUR7EQP leading, BUR9EQP trailing, correct?

If they do not have these are there other options I can use? I know I have read a thread that compared these plugs to others but I cant find it at the moment.

Thanks,
Ryan

Found these in a thread, I will go with the first to option to start and if they dont have those I will move to the next two.

BUR7EQP leading, BUR9EQP trailing

BUR7EQ leading, BUR9EQ trailing.

BR8EIX leading, BR9EIX trailing

Autolite AR3934 8 leading, AR3932 10 trailing

Changed the plugs and that didnt do it, had to get the autolites because nobady had any of the others. After cranking they didnt look wet at all. I then put the old plugs back in because I trusted them more.

Got it running with the help of starter fluid. Ran great until 45 degrees C, I think this is when the thermostat opened. The main problem is it wont start without starting fluid. Almost like it doesnt get fuel until it is firing on its own. Fuel pressure was about 45 when it was running and this is adjustable using my FPR. What should the fuel pressure be set to?





.

pump probably took a dump, 25psi is too low.

and how much gas did you put in?

I put 5 gallons in, and if I leave the key in the on position or when I am cranking I get whatever pressure I set the FPR to, it's adustable. The pump was just rewired, I guess this couldve put it over the edge. How can I check to see if the pump is dead?

Thanks,
Ryan

do a fuel volume test, can also do a static pressure test by clamping the return hose back to the tank.

Gonna do the volume test in a few minutes. Just to make sure I am doing it right, I will be disconnecting my fuel feed line from my rail. I will then turn my ignition on for 15 sec to see how much fuel has been cycled. According to Rotary performance this pump should flow 480 lb/min at 40 PSI base pressure and this then translates to .325 gallons in 15 sec. Seems like a hell of a lot of fuel.

you will have to drain it from the return line, otherwise you are testing the full volume of the pump at 0psi. the return side will be after the fuel pressure regulator and give you a volume test at the rated 40psi it should be putting out with no vacuum to the FPR. volume tests really should be done with the pump loaded to at least static fuel pressure that the fuel rails are seeing(or for the most accurate you would need to crank up the psi to what the rails will be seeing under boost which would be about 40psi plus xPSI of boost).

i also assume you mean 480lb/hr, unless it's a firehose. :)

Ended up not doing the test because as was going out to do battle Dave from Speed one called me. With his help we traced the problem bad to low power at the ECU wile cranking, the black/white wire was dropping to 7.80 volts and it needs atleast 9.50 for the ECU to stay on. Trace the problem back from there and one new Battery cable later I had 10.50-11 volts and startup on first crank.

Next thing I will do is adjust my TPS to try to correct my bucking on low speed decel and accel.

cool, glad you got that problem fixed.

Thank you, and thanks for your input on the issue.

One more question though. what is the blue/black wire that runs from the ECU all the way out to the diagnostic box? Dave said it was the fuel pump ground. Reason I ask is because in our diagnosis process we found the previous owner jumped a 12v source right to this wire at the diagnostics box and when we cut it the fuel pump no longer ran when the key was on. If this is actually actually a ground I am going to be lost as to why it is jumped to 12v.

Thanks again,
Ryan

that i do not know, it would have to have been rewired differently as the original fuel pump test connector turns the relays on to power up the pump when that pin is grounded.

Ya, something is definately rigged up somewhere along the line I will just have to trace it back. Dave was perplexed as to how this was wired. Speed 1 also did a fuel pump rewire but they did it off the battery and tapped into the stock wiring to keep everything clean, they assumed the stock wiring was still intact but I will have to sort things out.