89 NA vert

Things you should know,

I can’t check my engine light because the previous owner cut the connector off and use one of the wires for something else, I don’t really want to cut into it now not knowing what it does.

Ive replaced the fuel pump, cleaned and tested my injectors, replaced the fuel filter, and swapped to an S4 primary rail with the FPD deleted. All of this has been in attempt to fix my problem but I’m out of ideas.

Prior to any issues, all emissions were deleted but this was several years ago and I highly doubt is related.

here’s my issue, the car completely cuts out in fuel if I give it more than 10-15% throttle. If I give it less than that, it can rev out all the way with no issue. This will happen no matter where I’m at rpm wise, so before the secondary’s would even come on and after.

At idle, I have 30psi of fuel pressure and it will properly rise if I give it low throttle, however if I give it more than 10-15% the fuel cuts out and the pressure will rise until the car either dies or I let off the throttle. I have a video of this I can post on YouTube and share a link to if it would help you to see.

If I hold the throttle after it cuts, the car will die pretty quickly, if I let off before it dies it will backfire and then return to normal idle

Ive done the cheap vacuum test by spraying starting fluid on all the areas I think it could be leaking at while the car is running. I didn’t hear any rpm changes so I don’t think that’s my issues.

I’m starting to think it’s something electrical but I’m not sure where to start and would appreciate some advice.

Thanks everyone

 

What's your fuel pressure at idle when you disconnect the vacuum line on the pressure regulated. It's on the front of the secondary fuel rail. When disconnected fuel pressure should be much higher and should stall engine. The book says about 90 psi. I'm not an expert but 30 at idle sounds a little low. Also ck your ground on top of the rear rotor housing it's right in front of the bracket that holds up your intake manifold the ground strap has two black wires, this is your ground for the ECM, very important to take apart and clean without a good ground to the computer nothing works right. Good Luck.

 

I had similar issues. Altough mine where irregular, sometimes it would work fine but most of the time it would start showing signs of fuelcut and die id i didn't let of the throttle and give just a little bit of throttle.

My issues turned out to be that the wiring for the injectors where bad, replaced the bad section and plugs, after that it worked fine.
So if you still use original wiring, it could be that it's just old and crusty and needs replacing.