hello all!!
New member here and love the wealth of knowledge. I have a 1995 f-150 5.0 efi 2wd. after an oil gasket replacement I have developed a problem to where the engine will start but instantly die unless I press on the accelerator, and when I do step on the accelerator the engine will only rev to 500 rpm. the only code I have managed to obtain from the vehicle is a koeo 558. I have tested the evr and I am getting around 30 ohms and I have 12v power. another problem is when I disconnected the evr wires the wires cam out of the connector so I do not know which side the hot wire goes to. any advice with this issue would be accepted with much appreciation.


thank you,
Jusitn

 

EVR is theoretically, closed when it has no power to it. So again theoretically, if it's unplugged it shouldn't be making the motor crap out ??
Your problem sounds a bit like a TPS issue - might be worth the trouble to test that.
I have a 95 w/ a 302, next chance I get I'll try and get a look at which wires are where on mine.

 

Like chris said test your TPS, also check you vacuum lines (mainly the one to the EGR) for leaks, if you don't have a vacuum pump/gauge borrow one, or buy it as they come in super handy, to test for cracks. Spraying the lines with starter fluid or the like will identify a large crack but sometimes the smaller cracks that cause issues can't be detected/located with this method.

 

Looking at it from the wiring side (standing in front of the truck looking back at it) I've got the red wire on the right and the purple / white stripe wire on the left.
Also took a look at a 92 harness, it has a brown wire rather than a purple/ white stripe on the left but the wire on the right is red again.
And looking at it, power would open that switch and allow vacuum through, so unless it's stuck open, disconnecting power should close it.
Disconnecting vacuum there should close the EGR unless, again the EGR is stuck open.
I'm leaning more to the TPS, I think about Feb. 22nd or so I posted a how to on testing the TPS.