KA24DE Swap, intermittent spark, intermittent fuel - HELP!!!

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airman86
Posts: 320
Joined: Wed Feb 11, 2009 4:55 pm

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Well guys, after doing a lot of work on swapping a SOHC auto to DOHC 5 speed, i've made it all the way to where it's time to crank the car. The problems that I'm running into seem to be related to electrical problems.

First, I noticed that I wasn't getting any spark. I checked all of my connections and went to crank it again, and still got nothing. So, I switched gears and went to check for fuel. I have fuel pressure for sure, but I was only getting fuel from one injector. Friday night, I was only getting a pulse on injector #3. Got tired, fiddled around some more on saturday and I'm only getting a pulse on #2. I switched plugs around and continued to only get a pulse on #2, from each injector signal plug. So i'm going to guess I have an injector problem, but I found it weird that I had pulse from ONLY #3 to go to only #2 the next day. I don't hear any of the other injectors trying to pulse.

In the meantime, I noticed that I was getting spark out of the coil (it was arcing out). So I took a spark plug and plugged it into the coil wire to watch it fire - which it did well. Then I plugged the coil into the distributor, and took cylinder #1 wire and plugged the spark plug into that. Again, it fired, but it fell over and landed against the chassis while I was cranking it. Once that happened, the starter sounded very weak - like my battery was dying. Picked up the plug wire and moved it off of the chassis and cranking went back to normal. I don't know if that is unusual, but I've never seen that happen. I've grounded out plug wires to the chassis to see if I'm getting spark with other cars and nothing bad happens - but it may only be because I was cranking it.

Also, I think I've got a grounding issue. Before I could even get the starter motor to turn (it would only click), I had to run a jumper cable from the negative of the battery directly to the starter itself.

One more thing - while adjusting the distributor, I heard a relay clicking. Determined it was the EGI relay which I'm pretty sure is the fuel relay deal. But not sure. I just thought it was unusual.

So - my diagnosis: I definitely have some wiring/grounding issues. I've got some 8ga wire that I'm going to use to ground the engine to the chassis permanently. The negative on the battery has a solid ground to the chassis already.

I'm not much of an electrical expert but I know how to trace wires/etc. I've spent some time searching for this specific problem, but nothing has turned up to be close. I just need to know what wires I need to check and any other things to try!

Sorry for the long read, but I'd rather the KA experts have too much information than not enough :)


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OutToWinPAHC
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Well what did you do that caused these issues. Did you swap motors or something?. If your questioning ground then get a nice new ground wire. sand and wire brush the area where it mounts to the frame, and do the same to where it mounts to the block. Also dont forget the cylinder head ground (plugs needs that). So maybe replace the ground cables, charge the battery, and clean up the connections and terminals.

airman86
Posts: 320
Joined: Wed Feb 11, 2009 4:55 pm

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I bought the car in a non-running condition. So, there's no telling what could have happened to cause this to happen. As far as grounding the head and the engine block, they were grounded directly to the negative terminal with jumper cables.


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