Hi all, I swapped in a chipped P28 ecu with a basemap for my engine to my JDM 97 hatch with a D15B. I did the swap with a OBD2 to OBD1 conversion harness. The car runs great with the stock ecu, but as soon as I plug in the P28 ecu, the idle is really high (2000rpm). At first I thought it was a vacuum leak, but ruled it out.
Is there anything I'm missing from the swap that may have caused the high idle?

 

Yes. The chopped ECU doesn't have the same basic program to run your engine. Even the timing in the chip may be set differently. Until you know exactly what that chip has in it, i'd advise against running it at all unless you're getting it properly tuned.

 

Did your hatch originally have a two wire or three wire IACV ???

 

The tuner gave me a basemap based on the specs I gave him, the ecu I had at the time was faulty, so I didnt get to test it until recently...but.....see below

So apparently this was my problem, I have the conversion to do....I have the auto manifold with the holes blocked off, so Im going to have to drill the holes for the new IACV