sr20 will not run..... very weird circumstances

[landins13]

ok i have a red top sr20, fully built bottom end, stock head, custom equal length top mount manifold, gt28rs 50 trim, 550cc injectors hks rail/regulator, z32 maf, full turbo back apexi exhaust, greddy type r hg intercooler kit,apexi 1.1 mm head gasket, (clutch and other drivetrain mods to match engine, but arent really important right now)

ok so now my problem, i got my block back from the machine shop, reassembled the motor and had no compression, i took the head off bought a new head gasket and reassembled the motor. got it back in the car and fired it up to see if it would run, fires up right away no problem woo hoo right. turn it off after about 10 seconds because i hadnt put the radiator in yet. i came back the following day finished everything off, put the car back on the ground (off of jackstands) fired it up and everything was cherry, after about 10 min of running the engine shut off like someone turned the key. i went to start it back up and nothing, engine cranks but does not fire. i do not know why.

Things ive checked:
compression is where it should be on all 4 cylinders
timing is dead on
ignitor is good
mines ECU is good
all 4 coils work and are igniting when i crank the engine
fuel pump is good
injectors are good
fuses are good
MAF is good

so im left with the basic equation air+fuel+compression+spark = run

i have all the components but for some reason in my case
air+fuel+compression+spark= nothing

any help is greatly appreciated
and thanks in advance

PS: just thought of this YES THE CAR HAS FUEL

[GSXRJJordan]

Whenever I've had problems like that, it turns out to be a wiring problem (wire wasn't grounded, or a fuse blew, etc) or a vacuum leak (boost coupler blew off, IACV not connected, etc). If the mechanical stuff hasn't changed, and everything's plugged in still, and you hear the fuel pump prime (then shut off after 5 secs), and you have spark, you should be starting.

Make sure that you keep the battery charged throughout your troubleshooting. Next step is to doublecheck wiring and such, and start disconnecting things one at a time to see if you have a bad component.

[water]

PS: just thought of this YES THE CAR HAS FUEL

That's what I was just about to say haha.

Well like the above poster said, more than likely electrical. Maybe some wires got shifted around when you were dropping the engine back in and something got snagged, heated up, or whatever. Start with the basic stuff, check that the fuel pump is turning on, if everything is good, work your way up. Its the only way.

[landins13]

im wondering if anyone has any ideas as to what this might be?
fusesare all good, the only thing that has changed from the last time the car ran is i added an intake, its a 8 inch long piece of pipe from an old vw intake i had, i did this because everyone kept telling my that my maf was too close to the turbo and now that its moved the car wont run, thats the only thing i can think of but ive been working 90 hours a week and havent had time to check

[Sleepy240]

since you relocated the maf you should probably check the maf plug and the pigtail to make sure everything is in order. Like the previous posters mentioned it might be an electrical problem. It might not be a bad idea to check your grounds. Just for future reference does your starter click etc? (Some of the obvious things I know but these are typically where the problem is)

[landins13]

the engine cranks it sounds like it wants to fire but wont, it has compression it has spark it has fuel, it just wont actually start

[fcdrifter20]

double and tripple check all ur conections and grounds.everytime i have had a problem like that it has been something stupid like i left a plug loose and with the vibration of the enigne it came off completly. and re tighten all ur couplers, dont just look at them and say they look tight, take the time to check and retighten evry one of them

[landins13]

so here is the problem ...... i hope. the peg that holds my exhaust cam gear on my axhaust cam is broken it caused the gear that turns the cas to turn a tiny bit putting the car out of timing, hence i have fuel i have spark i have compression i have air but the engine doesnt run.
fortunatelly i have spare camshafts (i used to compare) im going to swap the cams and reset timing, i'll update once its in and hopefully that solves the problem

[landins13]

so that solved the problem for about 3 minutes of running, then the car puttered off and i cant hear my fuel pump prime when i turn the key
any ideas? i was thinking maybe the relays have gone bad or the fuel pump, i noticed when i was trying to start the car my fuel gauge wasnt reading anything

[landins13]

so i have a new issue which i need help on.... every time this thing runs something else goes wrong within 5 minutes..
anyways the new problem as previously stated i thought the problem was the camshaft and it was i swapped the exhaust cams and the motor started up no problem.

after about 5 minutes the car puttered itself off and would not start back up, when i turn the key i dont hear the fuel pump prime, i checked the fuses and replaced the relays and still nothing, i pulled the fuel pump out (Walbro 255) and inspected it, all my connections seem good but im not entirely sure how to tell if it is broken.
the pump only has maybe 1000 miles on it, i bought it new when i first did my swap but i didnt drive the car long before a speed bump killed my motor.
any advice is appreciated

[landins13]

come on guys nothing? no one has any ideas ?

[GSXRJJordan]

First check the pump. It should have between 2 and 5 ohms resistance between the positive and ground leads.

Then check that your ECU is grounding the fuel pump relay correctly. It's the black and pink wire running to the ECU. Ground it with the ignition on, and the fuel pump relay should click/the fuel pump should prime.

It's most likely a bad connection by whoever wired your SR in, or a fuel pump fuse.

[landins13]

when i turn the key the relay clicks but the fuel pump doesnt prime, i mean ive had the car running time and time again this is just the most recent issue. everytime i get the car to run something else goes wrong within 5 minutes

[landins13]

ive elimintated all of my problems but now my fuel pump wont prime.
My findings:
Car (http://www.zilvia.net/f/showthread.php?t=199437#) harness: = Walbro pump harness
Red = power (wire is good) Yellow w/ blue stripe
Black with silver slashes = ground (good) Black w/ red stripe
Black with silver slacher = ground (good) Black
Green = power (good) Yellow
Black w/ yellow stripe= ground White w/ purple stripe

ok so the last wire the black w/ yellow stripe using my test light i tester all ofthe wires (http://www.zilvia.net/f/showthread.php?t=199437#) the last one flashes briefly when you turn the ignition key on and off, when you turn it to on the light is bright when it flashes and when you turn it off the light is dim but still flashes. it only flashes once and very briefly so im trying to figure out what is wrong.

both the egi relay and egi pump relay are brand new i replaced them today. the ecu is good and im hoping the fuel pump is good its a walbro 255 with about 1000 miles on it. fuses are all good as well.

if anyone could also tell me how to wire up the relay seperate from the cars (http://www.zilvia.net/f/showthread.php?t=199437#) main harness that would be awsome.

Thanks in advance

[landins13]

bump....any help?

[cotbu]

Search Fuel pump hotwire!!

To rule out the pump take a jumper wire and jump pins 2 and 3 or 4 and 3 to see if the fuel pump powers, if it does, start your car.
shut it off, get your relay and fuse and hook them up accordingly.

OK heres one link Fuelpump Hotwire (http://www.zilvia.net/f/showthread.php?p=1478044#post1478044)

[landins13]

awsome dude thank you so much +rep

[landins13]

ok so i jumped the relay with the wire like it showed and i got nothing, im assuming that means the fuel pump went bad. i dont know how, its a brand new walbro 255 ive had it only a couple of months without ever driving the car on it.
the only thing im unsure of is my problem with the harness was a ground not a power soooo....i dont know

[lonelydrifter]

Take the pump out of the car and run power to it straight from your battery to see if it primes. If it works outside the car then at least you know not to throw it away.

Sounds like a wiring issue somewhere else down the line.

[cotbu]

That basically says the wiring to the pump is bad, your pump could still be good. With the jumper wire connect and key on, check the fuel pump socket plug for power. If theres no power then remove pump and power it externally, briefly!

If you can power it externally then you have a candidate for fuelpump hotwire or you could repair your wiring first.

[brian m]

Check the plug going into the ecu itself, make sure it's tight.
You might also crack open the ecu itself and see if the daughtboard is plugged in all the way.

It seems like this should be part of the standard troubleshooting checklist.
Fuel, spark, timing, ecu, coolant temp sensor, injectors, vacuum leak, pressure test.

[landins13]

so i discovered that it was in fact the fuel pump, i replaced it and everything worked fine, i still have a few bugs to work out, but i appreciate all of the input you guys have been great