No injector pulse!

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IHRAcer

Junior Member
Here's hoping someone can help me out just a little.......

I just finished replacing the engine in my 91 Accord EX with an engine from a 92 Accord DX. I did not check for any differences in the wiring harnesses before I began the swap, and now wish that I had. There are considerable differences between the harnesses, and so far I have rerouted and fixed everything so that the car will start and run if you spray carb cleaner into the throttle body, but I cannot figure out why there is no injector pulse. I really don't want to sink 10 or 20 bucks into a book that may or may not tell me what I need and possibly never use again. If someone can tell me the difference between the two harnesses so that I can find the appropriate wire to reroute, I would sure appreciate it.

Rick
 
Hmm... a 91 is an OBD0 car where as a 92 is OBD1... what harness did you use. did you use hte original harness from the 91? IF you didnt you should have.

obd0 uses peak and hold injectors with a resistor box...
obd1 uses saturated injectors without a resisitor box...
 
something else get the old injectors off your old motor, along with the wiring harness...
 
As far as I know, the 90-93 Accords are the same generation. My Chilton shows a resistor box for all 90-95 Accords and 85-95 Preludes. I did not have to change injectors for my H22 swap, and I know I have a resistor box.

what did you have to rewire? Have you checked to see if the fuel pump is operational, or did you check the injector pulse with a multimeter?

I did a 95 Accord to 92 Accord swap just a month or so ago and had the same problem. Car didn't want to start. Everything was wired properly, but no go. Just to say I did, I asked my friend to reset his alarm. Car fired right up. His alarm disabled the fuel pump.

I had my buddy turn the key to the on position with the banjo fitting from the fuel pump disconnected(being careful, rag over fitting, and keeping eyes clear of possible spray.) No fuel. I couldn't figure out why the pump wouldn't go, until we reset his Clifford.

We might be able to help more with a little more information.
 
Hmm... a 91 is an OBD0 car where as a 92 is OBD1... what harness did you use. did you use hte original harness from the 91?

No, I used the harness that was already on the 92 engine.

what did you have to rewire?I]

Had to add 2 ft. wire to oxygen sensor to reach around back, one of the plugs on the passenger side shock tower was a completely different style, but had almost all the right wires (based on color/tracers) so I changed the plug end to match. There were two wires in the largest plug that were originally in the smaller plug on the shock tower so I moved them over as well to the new plug end. Also, had to relocate a power wire from one connector to another at the distributor.

Have you checked to see if the fuel pump is operational, or did you check the injector pulse with a multimeter?

Have not verified FP operation, but the underhood relay is clicking on and off with key cycle. Checked injector pulse with noid light; nothing at all.

The 91 distributor has two plugs, one two wire and one eight wire. The 92 wiring harness has three plugs; two the same as the distributor and one four wire plug with three wires in it. I had to take the 12gauge wire (black w/ white tracer) out of the four wire plug and put it in place of the 12gauge wire (solid yellow) in the two wire connector to get power to the distributor and that gave me spark, but no pulse.

BTW, changing harnesses is out of the question at this point as I have already clipped connectors from the old one to help rewire. I had no idea that the factory changed so many things in one year on the same model car with the same engine. I guess that is why I wouldn't make a good engineer; I try to make things simple!

Rick
 
Originally posted by IHRAcer@Aug 3 2004, 05:14 AM
[
Had to add 2 ft. wire to oxygen sensor to reach around back, one of the plugs on the passenger side shock tower was a completely different style, but had almost all the right wires (based on color/tracers) so I changed the plug end to match. There were two wires in the largest plug that were originally in the smaller plug on the shock tower so I moved them over as well to the new plug end. Also, had to relocate a power wire from one connector to another at the distributor.

Have you checked to see if the fuel pump is operational, or did you check the injector pulse with a multimeter?

Have not verified FP operation, but the underhood relay is clicking on and off with key cycle. Checked injector pulse with noid light; nothing at all.

The 91 distributor has two plugs, one two wire and one eight wire. The 92 wiring harness has three plugs; two the same as the distributor and one four wire plug with three wires in it. I had to take the 12gauge wire (black w/ white tracer) out of the four wire plug and put it in place of the 12gauge wire (solid yellow) in the two wire connector to get power to the distributor and that gave me spark, but no pulse.

BTW, changing harnesses is out of the question at this point as I have already clipped connectors from the old one to help rewire. I had no idea that the factory changed so many things in one year on the same model car with the same engine. I guess that is why I wouldn't make a good engineer; I try to make things simple!

Rick
[post=371855]Quoted post[/post]​




A couple of thoughts.

Hindsight. Yeah, you should have used the original harness, but that's ok, let's move on.


There were two wires in the largest plug that were originally in the smaller plug on the shock tower so I moved them over as well to the new plug end.

This sounds important. You moved which wires from what harness to where? You kinda lost me there.
O2 sensor, no big deal.
Distributor, you did ok, since you have spark. Did you cut out the yellow wire, or just tap into it. I had to do something similar with my H22 swap, but I didn't abandon the yellow wire. I sent power from the black yellow to the yellow. Maybe that's what you did too......
Damn, I wish I were there to help. It's just hard to memorize every wire on your car. <_<
 
Sorry so long; worked 60hrs in 5 days this week, kinda beat!

Okay, I took a couple of pictures to help explain things a little better. This first one is of the wiring harness plugs on the passenger side shock tower.


harness.jpg



All of the wires from the 92 engine harness were the same (same being color/tracer/size) as the wires in that ugly brown plug on the car, but the plugs were different, so I popped them out of the 92 plug and wired them into the 91. The red wire and the yellow/red tracer wire (green arrows) didn't have any corresponding wires on the plug for the body harness where it was supposed to plug in, but there were two wires that matched in that ugly brown plug, so that's why I moved them as well.

Next picture is of the distributor wiring.


distributor.jpg



The big yellow wire sticking out by itself (yellow arrow) was originally in the 92 two-wire connector to the distributor, but had no voltage. The 4-wire plug on the left (also 92 engine harness) has no match on my 91 distributor, but the big black/yellow trace wire was 12 volt and placing it in the two-wire plug gave me spark, but no injector pulse. The car will run as long as you spray carb cleaner into the throttle body, so I am sure that everything is okay otherwise; I just need to find out what to rewire to get the injectors to fire.

Thanks for everyone's help so far!

Rick
 
OK. First off, I didn't remove the big yellow wire on the right from the plug on my engine. I don't know if that makes a difference. The large yellow alongside the blue wire, I left in place. I jumped a wire from the extra plug, into the black yellow to yellow combo. Black yellow and yellow connect. You might try that, but it may not be the problem.

I'm still kinda confused what you did exactly in the first picture. You had a strange engine harness plug, and a chassis plug that was slightly different. So you jumped the two wires to the plug that connects to the chassis, right? So two wires enter this plug that weren't there before, right? Did you run wires from that plug to their corresponding place, or were the wires already present at the chassis plug?

My stupid haynes shows the wiring as being the same from 90-92. I can't tell the difference from the book.

So try jumping power to the extra yellow wire at the distributor. It might have something to do with powering the injectors. I'm not sure.

If that's not it, then go into more detail about the chassis plug.

I've been busy for two days running a bachelor party, so no worries.
 
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