Swapped a s5 t2 in my s4 vert. When I turn my key to the one position I don't hear the fuel pump prime the system. I spray starting fluid in the intake and it fires up and runs like a champ! Turn it off and it don't start again... Has mild street port, walbro 255 pump, rc 550 main and rc 750 secondary, stock turbo, ported waste gate, n332 ecu, rtek 1.7, aem peak and hold 10 channel box,... I'm sure there's more... I don't know why but when the car starts it shows 30 lbs of fuel pressure but when I turn the key to "on" it doesn't show any pressure. I'm confused please help!!!

 

Jumper the fuel check connector and w/key to on listen for the sound of the fuel pump as it will not pump just w/the key to on unless you did the jumpering technique I suggested or opened the flap to the AFM.

 

Satch is right.

The fuel pump doesn't come on with the key on, but with the key in the "start" position, after the engine begins turning on it's own, the intake air opens the MAF enough to kick the internal switch to turn the fuel pump on.

My point is, it sounds like the part of the relay that controls the "start" part of the fuel pump has failed in some way.

Good luck man. Wiring problems can get... interesting.

 

Ok so yesterday I hotwired the fuel pump to a switch to ensure it was coming on. And now that I know it's turning on but the car still won't start on its own without the use of starter fluid!?!?! It makes no sense to me why it won't start.

 

have you tried a new fuel filter yet?

 

Fuel filter is brand new...

 

Check your AFM. I had one that had just a little catch in it. It took a lot of air flow to get it moving. I just cleaned the pivot point and used a light lube problem solved. If you have a leak betwen the AFM and the TB the results will be the same.
Dave NOOB to NOOB

 

Ok I'll check that. I know I sprayed some starter fluid on all gaskets to listen for idle changes but didn't have any leaks... Noob question: by afm you mean air/fuel meter? And where would that be located on the t2? Keep in mind this is my first fc... I'm used to workin on my 2 fb's...

 

I removed mine a long time ago but if I remember corectly it is right after the air filter. With the key on if you move it by hand you should hear the fuel pump kick on. It needs to move very easily so the slightest air flow will get you fuel.Yes AFM air flow meter.
Dave

 

For an S4 ECU. S5 pins are different locations.

Check the ECU reading for the Water Thermosensor and the Start signal as they play an integral role in starting a cold engine as a correct signal would tell the ECU to use more fuel when starting a cold engine. A bad signal and the ECU will use much less fuel to start the car. Pin 2I, Water Thermosensor, should read 2 to 3 volts w/key to on and a cold engine and .4 volts completely warmed. Pin 3B, starter signal, should be about 8 to ten volts w/key to start.

 

Which ecu do I have? It says n332. I'm gonna cheHattie's voltages tonight and if it doesn't read right what does that mean? Bad sensor or bad wiring? I guess I could mean either or both...


The ecu also is modded with rtek 1.7 when the car starts it has no 3k cold start idle. Would that have something to do with the water thermo sensor?

 

No it should not, and is your ECU an S4 or S5. And it being an rtek is not of any consequence. The 3000 rpm start up uses a temp switch at the bottom of the radiator, which is different than the Thermosensor located behind the water pump.

 

I'm not sure of the ecu. It was claimed to be an s5 but I didn't do the swap... It says n332. There's a koyo rad in the car with no sensors goin to it... The green plug to the back of the water pump goes to the ecu right?

 

Yes, and if it's an S4 it would be a Green/White wire. You can look up the ECU # to tell whether it's an S4 or not as I don't keep things like that committed to memory.

Edit:N326 - 86-87 NA
N332 - 87 Turbo
N327 - 88 NA
N333 - 88 Turbo
N338 - 88 Vert
N350 - 89 NA California
N351 - 89 NA
N352 - 89 Vert California
N353 - 89 Vert
N370 - 89 Turbo

 

[B]N332 - 87 Turbo [B]

O boy looks like I got the wrong ecu!?!? This could be my problem huh? I need the n370...

 

Wait a second.
your first statement is : Swapped an s5 TII into an S4 Vert.
Did you do the Swap yourself??
is the S5 engine running on the s4 Electronics?S4 Harness?..
this is a vital piece of info needed..you are leaving out info.

 

Yes sorry for the lack of info but I just got this car and I'm tryin to put the peices together so I'm learning this car as I go... It's an s5 block runnin off of s4 electronics harness, ecu, are s4

And yea sorry I worded it wrong I didn't do the swap. I just bought it this way.

 

Ok,well if the s4 electronics are running the S5 keg,that isn't a problem.
The ECU should be a N333 or N332.
Now,next thing:which injectors are you running??S4 or S5..Part # if possible.
If the harness is S4 N/A does it have a Resistor pack on it?(located by the front passenger side between the strut tower and front of car.looks like a silver box with a big connector on it)

 

I may be new here but I think you guys are getting a little crazy. It sounds like the air flow sensor isn't moving under cranking so not running the fuel pump. sticky afm or leak in piping to tb. check the easy stuff first. It runs well once started. Turn the key on lift the flapper to prime the fuel system if it starts I may be right if not I'm an idiot and you wasted two minutes of your life.
Dave

 

Yup the ecu is an n332 out of an 87' t2 and the injectors are all rc injectors. 550 primary's, and 750 secondary's. And that resistor pack I'm not sure of I gotta get a good look at it to see what your sayin

 

Afm is good I checked it with and ohm meter and has no stick to it. No leaks at the tb or and intake or injector gaskets. I was also worried about this not priming the system so I hardwired the pump to a switch to ensure that it's on. You deff not an idiot thanx for the advise though.

 

I don't see this resistor pack your talkin about. What does it look like and what does it do? Can you find a picture of it for me?

 

check the fuel filter and fuel pressure reg if it has one i am new to it

 

It's bolted to the passenger fender close to the air box. And you need to check pins 2I and 3B.

 

Yup as stated before fuel filter is new and regulator is good.