Gen5-Civic

I just replaced my D16Z6 with a JDM D15B engine. It started the first time, right away, and does so every time. It idles good, but if give it gas and try to hold an RPM above.. say 1500 the engine will rev up and down over and over. The higher the rpm you try to hold the faster it revs up and down.

I didn't know what parts on the new engine can be used and what parts I need to swap with the old engine, so I kept them all if it physically bolted in to everything. That being said, the fuel rail, throttle body, intake manifold, and distributor are off the D15B. Out of those parts, the only thing I saw that was different was the intake manifold is missing a valve/sensor in the back, the vacuum tube goes to the EVAP canistor, I plugged it and left it hanging, I also left the wire harness hanging that is suppose to go to the missing sensor.

Last issue. The lower left motor mount that attaches to the A/C bracket. I was trying to remove it from the chasis, both bolts are lose and won't come out so now the whole motor mount is loose. I think the nuts are tack welded to the inside of the chasis, and I broke that weld on both trying to unscrew it. So now what the heck do I do. Looks like I will have to cut out the bolts and buy a new motor mount and weld it in place.

Gen5-Civic

Guess I figured it out, not sure what it was though. I swapped plugs for the MAP and TPS, that made it worse, swapped them back. And now it runs like new! There were some things I did inbetween like disconnect the battery, oh and I went ahead and plugged in that old sensor/valve I was talking about and plugged the vacuum that is suppose to go to the intake manifold.

I haven't found many posts for swapping the D16Z6 with the JDM D15B, probably because they are so similar there is not much to post, that and most people don't swap the same stock engine in but this is my secondary daily driver so... Anyway, when I have time I will write up a seperate post with a few notes about the swap.