MPFI swap problems

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ibanez4string

Junior Member
first sorry for the length.

General problem: MPfi spudders but won't start and throttle cable loose.

In depth info:I am having some serious problems. First the reason I am doing the mpfi swap is I couldn’t figure out what was wrong with my dpfi. It was throwing a tps error code so I got antother tps and put it on with the dremel technique. No differenceIt would try not to idle, not just die but like the tach needle was magnetically drawn to 0. I would let off the gas and it would do this occasionally. Then sometimes it wouldn’t restart? Sometimes for as long as a day. So i thought it had something to do with fuel and spark or electronics. I assumed mpfi would replace all of these components.



1989 civic lx. Pm6 ecu, Si intake manifold(junkyard) , new manifold gasket. New coolant lines, new fuel filter, remanufactured injectors, SI distributor(junkyard), new thermostat and gasket. So here is what went in I followed this link http://www.fourthgenhatch.com/mpfi.html except for the injectors are wired backwards for me. So I went to fire it and nothing just turning. Checked for spark yup. Went to check for fuel and shot an injector out of the rail. I assumed no fuel was getting through, so I ran a power wire from a15 to the injector box. Now I crank and get a spudder. No matter how hard I mash the gas I just get a spudder. I assume it is all the fuel that was primed and nothing more. So I assume it is either the fuel pump which I can hear turn on and fuel does come out. But maybe this is why my car was cutting, it has intermittent operation, or something in the injector harness/wiring preventing more fuel from being given to the engine. I soldered all joints and checked for continuity as I went, I am going to go do it again, but I am at a loss. No error codes from computer while cranking, it blinks once when power is first added. Flipped distributor wires for shits and giggles and same thing.

Anther problem is the throttle cable, do I need an si cable? The stock one is loose until about half way, although the throttle works fine?

Thanks

Oh yeah and i searched for mpfi with no luck
 
Tighten the throttle cable.. you can use the stock DX or you can change to an Si, it looks cleaner.

the MPFI is weird, but really easy. You said you had the injectors wired backwards? Ever think thats the problem. Do you have the plug wires hook up correctly? 1-3-4-2 is the firing order. On the cap goes: Bottom Left, Top Left, Top Right then Bottom Right. Make sure these are correct. I think the inkectors being wired "backwards" is your probelm.
 
when i said wired backwards i meant if you look at the injector plugs on the fourth gen site, the red wire is on one side and mine is on the other. I got an si harness and didn't depin the injector plugs. So i think it is right or doesn't matter. How does the cylinder numbering go? 1 next to tranny or 1 next to driver? Is the firing order different from the si to lx or at least location on cap? I simply took one wire off at at time and transferred to new distributor. Thanks.
Tyler

Throttle cable worked thanks, uh i must have eft my brain in the toolbox on that one.
 
In the swap guides they say that the power wire for each injector is on the left and the ground is on the right. Run your corresponding wires(2 from ecu and 2 from engine harness) to each injector. Then run a ground wire from each injector to each red/black wire on the resistor box.

Did you try switching the 2 white wires at the distrubutor plug around? Mine wouldnt start at first and this was the problem.

Hope this helps
 
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