I have a LS/vtec (gsr head) motor in my integra. I had rc 330 injectors installed and had the p72 tuned for it. I ran that setup for a year or so and decided to go FI. I swapped out the injectors for 450cc and swapped out the ECU and had it tuned for FI. Car ran fine with no issues, but I decided I wanted to go back to NA. I took off all of the turbo parts (intercooler, injectors, 3" exhaust, etc) and pieced back together the car with stock parts over a span of roughly 8 months. It was not started. I put back the RC injectors and ECU i had with the setup before when I was NA, put on stock header/exhaust, intake, etc. Now the car wont start. It will turn over and crank over and over and over, but will not run. I sprayed some starting fluid in the intake manifold and it runs roughly for just a second. I figured might be bad gas so I un hooked the fuel line from the fuel pressure regulator and turned the ignition on and off (cycling the fuel pump) to pump out bad gas. I pumped out about a gallon of fuel. the car sat with minimal fuel in it (had the fuel light on). I put in 4 gallons of new gas and still will not start. I hear the fuel pump start when i turn the key (and obviously its pumping gas since it would come out the FPR when i turn the key). Any other ideas? Thanks in advance.

cliff notes:
Was NA, ran fine
went FI, ran fine
went back NA with same parts prior
car wont start.

 

Sounds like injectors are not pulsing.

Start by confirming you have power to the injectors, lead that is the same color at all 4 injectors should test as 12V+ when ign. switch is in the run AND start positions.

If you have power, get a noid light and make sure you have injector pulse, [ground pulse from ECU/ECM.

What year is the car/engine?94

 

thanks for the reply. I have lights on the injector clips, are they supposed to be lit up with IGN on?

 

^ sounds like injectors are bad or dirty or clogged from bad fuel. Test ur injectors or if u can try to use different injectors and see if it starts, if it starts then u know its ur injectors.

Another thing u can check is ur fuel filter. Also check ur fuel pressure with a gauge or install one permanently

 

hmm, ill check the injectors when I get home. I used the plug and play resistor box for the injectors when I was FI. Meaning I took the cap off that plug, does that cap do anything (needed for injectors to work properly?)

 

Ooooooh, so u left the cap off the plug on the harness where the injectors wires run to?

Yes if u left cap off then that's ur problem. Put it back on cause that's what connects ground and power to the ecu.

 

this is the cap im talking about. I think i threw it away....

http://civic-eg.com/pics/diy/resistor_box2/DSCN4405.jpg

 

Aw man... Not good. If u take a look in the plug, it needs prongs from that cap to connect them together for power and ground to the injectors.

You need that cap bro... Start digging thru trash or Find one at a junkyard shouldn't b much for it.

 

That will be the problem, maybe.

You said, "I have lights on the injector clips, are they supposed to be lit up with IGN on?", are you saying that the "lights" you have on the injector clips will turn on, [stay on] when you turn on the ign.?

If so, that is not right at all, if the jumper plug, [cap] was not in place or resister box not plugged in, there would be no power to the injectors, [clips] so the lights could not turn on.

If the cap or resister box was in place, [or injector power leads are connected together some other way] you would have power to the injectors but a ground "pulse", [not a steady ground] is sent to each injector and only when engine is running or cranking.

If, as you say a light bulb connected to the injector clips is on as long as ign is on, it would mean the injector is open and filling, [flooding] cylinder with gas, engine will not start.

You can also remove the fuel rail, leave the injectors connected, lay the assembly on some rags, and turn on the ign., no fuel should be spraying from any injector.
Turn ign. switch to start, the injectors should now spray one at a time in "firing order".

JFYI, the "cap" connects the power leads for the injectors when a resister box is not used, not grounds, as Eg.ls.turbo indicates, the ground, [ground pulse] for the injectors is supplied by the ECU/ECM. 94

 

let me clarify...I have leds on the injector clips, BUT they do not light up. I am wondering when they are supposed to light up.

 

It's suppose to light up to show u if it has power goin thru the injectors. If it's not lighted up then u have no power to the injectors.

 

thanks guys for the help! i found the plug and it started right up!

 

Not exactly, it will tell you if you have or have not either a ground pulse from the ECU/ECM or 12V+ from ign.

But you are right if the jumper plug or resistor box is not plugged in there will no power.

I was going on what I thought the OP said, he has lights at the injector clips, not he has lights that do not light up. 94

 

Oh ok gotcha

 

What # u puttin down?before u switch back na?