B18C swap p0171

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Only problem would be for inspection, they will fail me automatically if the check engine light is on. And last time I took one in chipped their scanner would not connect to it.
So if I do go the p72 route I'd have to change out the IM too.
 
There are usdm obdII p30 ecus. They are rare. only came in the 96-97 del sol vtec. will be a little under fueled but would run the car fine for the scanner. just don't take it over 6k.
 
The evap system has two vacuum lines. The one off your TB and the one off the actual evap purge solenoid (much smaller of a line). They both go straight to the charcoal cansiter mounted on the firewall.
 
There are usdm obdII p30 ecus. They are rare. only came in the 96-97 del sol vtec. will be a little under fueled but would run the car fine for the scanner. just don't take it over 6k.

Sounds like that would be a hard find then if it is that rare.

I was wondering if I get injectors with higher cc capacity I wounded if thy could solve the lean problem. Or would it not matter if I get bigger injectors because it controlled by the ecu anyways.
 
The evap system has two vacuum lines. The one off your TB and the one off the actual evap purge solenoid (much smaller of a line). They both go straight to the charcoal cansiter mounted on the firewall.

My evap solenoid only has 2 lines, same size. One to TB other to the canister.
But there the same size
 
I just took a look at the charcoal canister and it just has 2 connections one for the fuel tank and the other to the EVAP valve
 
Hmmmm. My EH3 has 3 lines.

Edit: my K20A swap (OBD2) only needs two like you mentioned. I plugged the third (smaller one) and it just hangs in the bay.
 
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Well according to the manual B18C1,B18C5 and B18B1 utilize a charcoal canister with two connections points.

Now opposite from those two connection points there is a "to EVAP 3-way connection valve" and my car does have this yet I don't think that that is what you meant by the second vacuum source as that 3-way connection point uses an even larger vacuum hose.

On the canister the 3-way connection valve leads to a little plastic square piece. So according to the manual the canister is correct?? I guess, but I still am not sure.

Thank again for your help



Edit:Also you mentioned that your third vacuum connection just hangs?

From where? If you have a chance anytime this week could you possibly take a picture please.

I am still confused about this third vacuum line. Also EH3's have B16 engines right?
 
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I have one line that came of the canister to the TB. Another line to the fuel tank. And the third smaller line went to my stock D16Z6 evap purge solenoid. Then I swapped in a B18B1 and it was the same. And then I swapped in a B16A in the same spot (all were mounted on the back of the IM on driver's side). But these swaps were all OBD1 and they are probably different (especially since my current swap is like your evap set up). All I did was put a screw into the vacuum line to plug it. I have all systems including both O2's. No CEL. Not many virgin ECU K-Swaps can say that :cool: lol

In any event....I really think its something with the injector wiring. Or the positive crank pressure thing. But the fact that it had a different injection system on it makes me think something isn't right there.
 
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:shades::D
Right on, that's quite an accomplishment on the K20 swap.

I wish it was just the injectors. I checked for continuity on the four (+) wires of the injectors and they are all ok. From the harness to the injector plugs they correspond correctly. On all four of these wires I got 0.000 which means that the circuits are closed.

Now when I did check the corresponding grounds for the injectors on all four (-) I got 1.77 of resistance. I am going to look for a loose ground or pin in the harness. I'm not sure if this resistance can be the problem but I sure hope I can figure it out soon.
 
Alright so I worked some more on it today. I found out that the yellow/black wires in the injector plugs were the ones that gave me the +12v with the key on engine off. So the brown,blue,red, yellow wires are not the power supply for the injectors I guess.

The yellow/black IGP1 and IGP2 in connector A of the ecu harness though are the ones that still have the resistance in them. I couldn't figure it out why though. I know that these wires run through the main relay and I also believe the primary o2 sensor, evap, and iac valve.

So I went ahead and did a continuity check between the primary and secondary o2 sensors and the ecu harness and they all checked out ok, 0.000. I just cant figure out that resistance in the yellow/black wires IGP1 and IGP2

feel like :surrender:
 
The wires on the injectors that are the same color (yellow/black) are power like you said. The other wire are triggers from the ecu telling the injector(s) to open. They are a ground signal that is sent like a quick pulse telling each injector when to open. A noid tester should work to check.....but I've never done it. I would think a multimeter will get you there too.
 
Well no progress on the problem thus far. I am going to try to find some replacement injectors from a scrap yard and hopefully see different fuel trim numbers.
 
Well I ended up finding some injectors online from a 98 gsr that are supposed to be 240cc. I exchanged the injectors and initially the fuel trims would be -4% to -10% and as it warmed up it ranged between -12% to -20%. So the ecu is now subtracting some fuel. But it is not as bad as it was with the supposedly civic vtec injectors. I drove the car for a while and the fuel trims would fluctuate between 6% to -4% while driving depending on acceleration but during idle the fuel would steadily climb to -16%.

What I am going to re-check next is the valve timing hopefully this can help regulate the fuel trims closer to 0%
 
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Drove the civic a little today. The hesitation and stumbling has gone away.

I was thinking that the addition of the fuel with the old injectors was 46% (about 40-42% warm)if the injectors were 180cc injectors from a standard d series honda;
180x46%=82.8
180+82.8= 262.8cc

So all along I guess the fuel trims were giving me the answer. The fuel trims today alternated steadily between -4.5% to -11% which is much better than yesterday.

To solve the removal of excess fuel I will next adjust the idle screw which I remember the mechanic closed because with the old injectors there was a false lean condition.
 
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