Ok, me and my roomate were thinking yesterday and were wondering, if your car was running in open loop all the time and run rich out the @$$, then what if we took a signal from the distributor and sent it to the fuel injectors. Then the computer could not screw up anything, and we would have mechanical fuel injection right? My objection to this? Im pretty sure the computer makes the car run rich or lean by sending a longer or shorter spark length to the injectors, but the distributors would be sending a pulse all the time, no change, yet of course it will increase in speed with RPM's. Anywyas, just wanted to know yalls thoughts on this. Thanks guys,

 

You answered basically one reason this wouldn't work.

The computer does so much more then just read off one input too so theres good reason to keep it. If the sensors are working and the chip is setup right there is no reason for the car to run with the wrong fuel ratio.

 

Yeah, but thats what brought up the discussion, is because my car is throwing codes everywhere, and basically everytime I start it it is in open loop, which we all know helps performance. So we were conjuring up ideas to make it stop. Anyways, thanks guys,

 

TTT, to get more input.

 

I assume you have a "check engine" light on, what code is it throwing? Of course it's going to run ****ty and very rich in limp mode. Why not fix the reason why it runs in open loop all the time?

GM and any other factory computers, run off of many different signals, not just rpm vs. inj. pulse width. They take in account of engine load, air temp, coolant temp, EGR, just crusing or WOT, TPS, O2 sensor, etc.

Maybe your eprom is fuct, or the ecu/ecm itself.

 

Uh, first off, mechanical fuel injection is uh, mechanical... like, no electricity, dig?

Secondly, fuel requirements are not linear to just rpm. Im making the assumption that you mean you want to run injectors straight off the dist. signal, i.e. relative to the rpm. If a car was so simple to run then why wouldnt we all just develop our own injection systems?

Heres a crazy idea, how about you try and learn a thing or two by actually fixing what is wrong with it. Pick up a chiltons manual and start from there.

 

very well said pablo