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grip addict
02-12-2007, 01:06 AM
hi all, i have a 90 gt4 with a stock motor that i've been working on over the past year. it idled just fine when i took everything apart...
stock block, head, ignitor, afm, ats ecu flash, 550's, bored fuel rail, jza80 pump, ac delete (so no ac idle up) egr delete (plates blocked, lines checked and capped) csi delete (blocked at fuel rail, csi installed on intake man but not plugged in)

got everything together and turned the key and it ran! for about 15 secs. then it just shut off. i've been messing with it over the past week and no luck, its still doing the same thing.

this is what i've swapped with a friend's car/checked
afm, ecu, throttle body (for isc, tps). am going to check the ignitor sometime this week.

it really sounds like a fuel issue to me, i'm gonna borrow a fuel pressure gauge and see whats going on. anyone have any suggestions?

alltracman78
02-12-2007, 01:10 AM
Check for fuel and spark.
Any codes from the ECU?

grip addict
02-12-2007, 01:42 AM
only code i get is 51, and both ac and tps are represented on that code. i don't have the ac idle up anymore, so i imagine thats why the code's there, as i checked the isc today. lookin at the bgb right now to see about where to hook up the fuel pressure gauge... arf

i havn't timed the motor yet, but that shouldn't make it die after 15 secs, rigiht?

andy
02-12-2007, 03:21 AM
sounds like your fuel pump is getting cut off.

alltracman78
02-12-2007, 03:53 AM
only code i get is 51, and both ac and tps are represented on that code. i don't have the ac idle up anymore, so i imagine thats why the code's there, as i checked the isc today. lookin at the bgb right now to see about where to hook up the fuel pressure gauge... arf

i havn't timed the motor yet, but that shouldn't make it die after 15 secs, rigiht?

51 has nothing to do with the AC idle up.
It simply means the AC is turned on when TE1 and E1 are jumped.
OR the idle range in the TPS isn't actuated when they are jumped.
So, unless you
A-had the AC turned on
B-had your foot on the gas pedal

Your TPS is out of adjustment or bad.

I don't see the TPS not allowing the engine to run.
Having the ignition timing extremely off SHOULDN'T cause the engine to die, but :shrug:
Will it run if you hold the throttle down [not all the way, just partial].
Also you could try messing with the dist in the 15 sec it is running.
Just don't ground yourself to the chassis. :D

It is also possible something is turning the fuel pump off.
Check that fuel pressure and get back to us.
Keep in mind the pressure might hold for a bit after the engine is running...
Try bridging FP and B+ in the diag box. This will bypass all controls for the pump and it will continue to run as long as the key is on.

grip addict
02-18-2007, 10:58 PM
so i bridged those terminals and it ran just fine. i was able to time it and get started on the first 20 miles of the break in. that being said... the car hesitates a little bit (not every time), idles at 2000 (vac is steady at 20.5) and is fast as fuck.
sound like a fuel pump relay to you guys? i think i need to replace it now. i want to get it fixed asap, but i wont do any damage by driving around a little with the terminals bridged, right?

grip addict
03-05-2007, 08:21 AM
update-
i have about 500 miles on the motor now. i pulled the wire out of the diag box and it still acts the same. i havn't had a chance to swap ignitors or fuel pump relays yet (Friend is in mexico on vacation for a little while longer)

it still idles at 2k. vac here is ~21
on cold starts, and when running off the turbo timer the rpms bounce between 1500 and 2k. if i try to rev it when its cold it sputters. when i start it warm it the rpms bounce once or twice, i presume pressurizing the fuel rail. sometimes when i'm driving in the higher rpms it will shake violently, ususally if i shift too quickly. it also feels like a loss of power sometimtes (maybe ecu pulling timing?) up high. i'm back on stock ic until i get a chance to remount the RC wta tues.

will let you guys know. btw even at 10 psi the td06 is so much better than the ct26.

kira
03-12-2007, 01:25 PM
anybody know where is location of FUEL PUMP RELAY 95 GT