Bought used engine, getting no fuel but have fuel pressure
 

I really need some advice here. I picked up a used NA engine for my 86 RX7. The guy said that the engine ran fine before and it was from his 86 RX7.

Well after a long weekend my dad and I finally got the engine in the car. We bolt everything up but had to do a bit of wire splicing due to the previous owner cutting the harness since he didn't want to pull the UIM to disconnect everything. Wasn't much to splice but I have a bit of concern that the wires may be different.

We try to start up the engine but no go! The engine will spin but refuses to fire. I am not getting any fuel to the rotars at all. I even pull the fuel rail and put my good injectors on just to test. I am getting fuel pressure to the fuel rail, but no fuel is entering the rotars. The plugs are dry.

We tried starting fluid to see if it would try to start and it did. But still dry plugs. Then something odd happened! The motor was making the standard attemt to start by going whir-whir-whir, but then it stopped making the compression sounds and was just going whirrrrrrr.

So questions:

1)What would prevent fuel from getting into the combustion chambers even though I have fuel pressure? Fuel pressure is present at the front of the fuel rail but not getting into the injecters if that makes sense. I even changed around the fuel in and out lines to test.

2)Why would the engine not make the compression sounds anymore when attempting to start? Could a chain have slipped?

3)I am a bit concerned about the wiring splicing, would anything under the UIM prevent the motor from starting if the wiring was off? I am not popping fuses either.

Please help me get this beast running again guys! I am super frustrated but have hope :)

Well after a long weekend my dad and I finally got the engine in the car. We bolt everything up but had to do a bit of wire splicing due to the previous owner cutting the harness since he didn't want to pull the UIM to disconnect everything. Wasn't much to splice but I have a bit of concern that the wires may be different.


I hope you ended taking out all the spliced wires. And removing the uim and actually using your origainal harness on. I would double check everything. Also check your main fuse (80A)
If you are getting pressure, fuel line should be working. Did you remember to connect the AFM? Another thing i can think of right now is are you using your old injectors or his?. If so get them checked or even get them blue printed and cleaned.

Simple. Go to one of the secondary injectors and pull its plug off.

With a meter check to see if ONE of the wires of the two has 12vdc or not. PROBABLY not.

So you don't have power going to the injectors is your problem. I'd say go look at your solneoid resistor package and make sure it's plugged up to the harness. It's located below the afm/filter and mounted on the fender with two nuts. It has a aluminum cover and has one large electrical connector going to it. IF it's there, the pull the plug off and make sure the center wire on the connector has 12vdc. It should be a black/yellow wire.

It would have been simpler to pull the dynamic chamber off and install YOUR original harness in tact to the engine. I have splice the thirty to forty wires to the engine in the past and it worked just fine BUT is NOT as staight fwd as some would think. Really depends where they cut it though.