Another GC8 engine swap Q.

[wurkenman]

We got the car going after the JDM EJ20 engine swap into the 92 Legacy. It pulls like a raped ape. Having a couple of issues still. It is throwing 2 CEL codes. 1 Atmospheric sensor, and 2 Waste gate control.

When accelerating hard and the foot is pinned to the floor, every once in a while it stumbles hard. Very violent kind of like the ignition is just cutting off, or the fuel supply is gone. Then it comes right back. Anyone ever experience this? If you don not pin the pedal to the floor and stay just shy of it, the stumble does not occur.

Just wondering what the little are and how to fix them.
Thanks again
Terry

[kimokalihi]

I also had this issue for the longest time. It turned out to be the spark plug gap was too big. I had it gapped at .040". Just a couple weeks ago I gapped them at .030 and the problem is history.

Do you have a boost gauge? Check to see if it only does it once you reach a certain level of boost. Mine was doing it when I got to 15lbs. Now it boosts 18+ easy.

[wurkenman]

Yes we have a boost gauge installed. The boost only goes to about 8-9. I will double check the plug gap. Any guess about the 2 codes?
Thanks

[kimokalihi]

I forgot about the codes. Maybe they're not hooked up right? Or they're damaged. I don't know.

[wurkenman]

The car the engine is in was a NON turbo model. I do not have either of these sensors. I need to go top the bone yard and see if I can find some, but I do not know what I'm looking for. Can someone post a pic or at least tell me where and what to look for.
Thanks
Terry

[kimokalihi]

Oh well there's your problem right there lol. I think you just need all the stuff that's next to the air box on the passenger (left) side strut tower.

[Legacy777]

Add the sensors and verify the wiring. Once you've fixed the sensor issues, you will likely take care of the boost issue.

[wurkenman]

Thanks for everyone's help. It ended up being the COP system. All the coils were cracked. We got some at the bone yard off of an SVX. The engine only had 15K on it and all the coils were like new. I bought all six. Now it boosts and runs like a scalded dog. Still does not want to idle when cold, but at least it runs.

Here are some pics as promised.

[Legacy777]

Looks good, and glad to hear it's running better with the new coils.