no start... coolant temp sensor?

[Jay_D_EmmS13]

all right, here we go. i have a 90 240sx that i installed a walbro fuel pump and some 460cc injectors, a tuned ecu and drove the car for a week. all of a sudden when i was going to my parents house it shut off and wouldn't start (normal crank until it drained the battery) even after my battery was without enough power to start my car, (about 10 minutes go by) i simply rolled my car about 1 foot in reverse and popped the clutch and without any hesitation it started. so i drove for another 1/2 mile when it shut off again.

the next day i got my stock injectors and ecu, thinking that maybe that was the probblem, but the same problem occurred. it is definitely not getting fuel, but the pump primes and works fine (my belief now is only when it's cold).

i know i have a coolant leak from somewhere but i haven't been able to identify where it comes from, so i've been replacing coolant every few days. i read the fsm for no fuel no start and it said that the cts is possibly a problem. i also read the code on my ecu; although i'm getting several codes, i think it's because of the faulty cts. several times i've waited until the car was cold and it started normally, then would die when it warmed up. i've checked all the relays, fuses etc.

i'm just looking for some insight and possibly to help anyone that experiences the same problem.

[dkdeleon68]

how do you know its not getting fuel? are your injectors pulsing? get a noid light to check the injector pulse

[Jay_D_EmmS13]

well, i took a fuel line off and cranked the engine expecting to see spewing fuel but naught

[Jay_D_EmmS13]

not only that, the fuel pump wasn't even priming (after it would run for a few minutes then shut off)

[dkdeleon68]

not only that, the fuel pump wasn't even priming (after it would run for a few minutes then shut off)

Thats what it does it just primes the injectors for starting then shuts off until you start the motor then it starts pumping again. The fuel will not spew out it will leak slowly to prime.Which fuel line did you take off? I'm sure you know already but the fuel lines that connect to the fuel rail is a feed line and a return line. unplug the fuel line that is connected to the fuel filter. Im sure thats what you did but im just double checking. have you checked fuel filter for clogging or the fuel pressure regulator?

another thing to check is your installation of the walbro pump and fuel line coming off of the pump.

[Jay_D_EmmS13]

the filter and pump are new; but i checked them for proper function regardless of their condition. when i took the fuel line off i only got the residual fuel that was already in the line. the fuel pump is loud enough to hear when the key is turned, and even though i expected "spewing" of fuel, i didn't even get a constant flow. i'm certain the problem lies outside of my fuel, however the fuel system is affected by the underlying issue

[Jay_D_EmmS13]

so nobody has ever experienced a problem like this before with his car? un-freakin-believable.

[BoBa524]

dude really sounds like ur pump crapped out. you listed all of these mods for the fuel system how are you pushing in air compensate for all that fuel? pull your plugs smell them, let the cylinders dry. replace plugs if needed. install your oe pump. if ur pump worked you'd have pressure upon turning the key.

[Jay_D_EmmS13]

i understand what you guys are saying, but i don't think you understand me. my car will run for about 5-10 minutes then shut off. if i wait another 10-15 minutes it will start back up. but if i try to start it right after it shuts down, it will just crank. i could go out and drive it right now but after a while it will shut down. if it was a fuel problem why would it start at all?

i know i have a cooling problem, and i had one before. when i first installed the engine and transmission it wouldn't idle. i read the fsm and fixed it by cleaning my coolant temp sensor. since my car is at my parents' house i can't do anything to it. i kinda just wanted a second opinion to see if anyone had this same problem. the fsm (and the trouble code on my ecu) says check the cts so that's what i'm gong to do when i get the chance. i've already checked out the full fuel system and the fuel system itself works fine.

[dkdeleon68]

sounds like its flooding itself out. check your oil to see if it smells like gas.

[Jay_D_EmmS13]

thanks guys, you were right. it was my coolant temp sensor. my car runs great now!