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error2k

New Member
I just got done doing the wiring for an OBD0 to OBD1 conversion on my EF civic, and (surprise surprise) it doesn't start. I'm too tired tonight to keep going at it, but I did manage to find that I don't have any spark, I do have fuel, and the only trouble codes I'm getting is for my O2 sensor which admitidly I havn't hooked up and wired in yet. In my mind, the absense of an O2 sensor wouldn't throw the computer into a tizzy and pull the spark, would it? If I had wired the TDC/CKP/CYP sensors wrong, it would probably kill the spark, but wouldn't the ECU catch it and throw a code? By no means am I looking for a magical end-all answer to this, as I still have alot of avenues to look down, but I am looking for suggestions and any useful input, thanks.
 
the car will run with out the o2, but poorly and will throw a code.

fix the o2, then pull the codes. it will tell you whats wrong. Codes are in our reference section.
 
Round 2

After some work and wire checking, I discovered that I had about 4 of the distributor wires mixed up.Fixed that, and now it has great spark.......but now no fuel. Main relay is fine (swapped it with a friend that has a known working one), but it seems as though it doesn't send 12v to the pump. There is continuity between the plug on the main relay connector and the plug that connects to the pump through the black and yellow wire. There isn't any priming sound when the key is switched on nor will gas will come out of the line going to the fuel filter when hose is loosened and the key is switched on. I still want to send 12v to the black and yellow wire on the pump, and check that the injectors are getting a signal, but it seems as though the finger is pointing at the fuel pump. The only confusion left in my mind goes back to the fact that there is continuity going to the pump, but no power.....even after swapping relays. Any advice? Is there some silly fuse that I'm overlooking? Thanks in advance.
 
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the fuel pump runs off a fuse under the hood by the battery. i beleive it is a 15 or 20amp fuse. check that.
 
Tonights update

Ok, so I used a service manual to check the main relay, the pump, and the wiring inbeween. The main relay checked out ok according to the service manual tests, which isn't a surprise because I tried swapping a known working relay before. The pump turned on when I sent 12 to it by jumping the #5 and #7 positions on the relay plug together, as the service manual specified, and there is continuity in the wire going from the main relay plug to the fuel pump connector. But, when I look for voltage going to the pump when the relay is connected and the key is in the On position, it isnt there. The only complication I might be overlooking is the fact that there's a slight wiring difference (from the factory) between DPFI and MPFI EF civics concerning where the injectors are connected to. On DPFI cars it looks as though they go from A1, A3, A5, and A7 to the fuel pump's power wire. On MPFI cars it goes from A1, A3, A5, and A7 to A15 and A13 on the ECU...which in also connected to pin #3 on the main relay. I would greatly appreciate any help.
edit: for the record, my car is a 91 civic dx with an mpfi conversion, and now a z6 with a conversion harness, obd1 dizzy, and p28 ecu.
 
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Has fuel now, odd spark?

Ok, after rigging the fuel pump to manual control (I gave up on trying to make the relay give me power....I'm positive the relay is ok, its the wires going to and from that I'm questioning) and trying to start it, it hammers and might run for a few seconds...but it sounds like an ATV that has a shitty idle, then it dies. Number 3 and 4 exhaust runners are warm, 1 and 2 are cold. The spark plugs from number 1 and 2 are covered in gas, and when the plugs are taken out and grounded they give a brilliant spark. I even had the presense of mind to stop cranking right after the number 1 sparked to see where the cam timing mark was....and it showed that it had just passed TDC, so firing order isn't the issue. Is it possible that the number 1 and 2 fuel injector connectors are reveresed? Also....strictly hypothetically speaking, what would the lack of a TPS do? I'm starting to think that this car is haunted :ph34r:.
 
Round 3: Fight!

So, she's sporting a TPS now, reversed the 1 and 2 injector plugs, and made definate progress. If I try to start it with no throttle, it fires and dies right away. If i do it with just a little throttle (what I imagine would bring it to 2k rpm or so) it starts up, but I have to madly fluctuate the throttle in order to keep it running. It acts like its running rich, and when the whole specticle is over with exhaust runners 4 and 3 are the warmest, 2 is a little less warm, and 1 is almost cold. Pulling the #1 plug reveals no gas on the plug, and the plug itself is a little warmer than room temperature (considering its in a cold garage, it feels about the same temp as my hand). It's been suggested that one of my TDC/CYP/CKP sensors may be mis-wired, but I'm thinking that if that were the case, the engine wouldn't even be able to do what its doing now.....but I will look into it. I was also wondering if base timing could be so far off that it could be the culprit, or maybe fouled plugs? Vacuum lines *appear* to be all correct, but I'll have to go over those too. Am I missing anything? Anyone ever heard of a case like this before?
 
Issues solved

After much confusion and wire-tracing, I discovered that the person that swapped the engine into the car had the EACV and IAT connectors switched around. I still have to set the TPS to the right idle voltage and do the timing, but other than that its running normally. Now I have to fab an exhaust for it.... running an open header really makes the neighbors happy. Maybe a Garrett will hush it up a bit? ;)
 
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