I have been battling this problem for quite awhile now.
I picked up a 1030 ems for my d17a2 about a year ago. Put it in with my turbo, had it tuned and had a blast for about a month. Heater hose blew off the back of the block and blew the headgasket. I replaced it and put everything back together, then went to start it and nothing. Pushed it and popped the clutch and it ran but it ran terribly.

I shut it off and popped the hood when I noticed I forgot to hook the engine ground back up. I bolted it back down, then started the car and it still ran rough. I drove it around for a bit and it evened out a little but still hiccuped just a little. I saw on the wideband that it would go slightly lean under boost.

I figured it was an issue in the tune somewhere, so I was on my way back to my tuner's shop and the #4 rod disintegrated and shot through the block and oil pan. After that, I built a new motor with pistons and rods and dropped it in about two months ago. I retuned and the problem again surfaced.

Since that, I've replaced everything I can think of that would tie into a timing error. I've replaced all of my coil packs, plugs, crank and cam sensor, crank timing gear, alternator, put in a 4 gauge ground wire, replaced my entire engine bay wiring harness and nothing has gotten rid of the problem. The timing errors occur under all conditions, regardless of throttle, rpm or load. They are very sporadic and random. Sometimes the car will run for 10 minutes without counting another error, sometimes it will count up 2 or 3 at a time within a few minutes.

I've spoken with AEM techs, sent them datalog files as well as a few tuners. Everything they've come up with as a possiblility hasn't solved the issue. The issue isn't in the map or the ecu. I have loaded a friend's map and it still gives errors. I've also put in a completely different 1030 ems with my map and my friend's map and nothing has worked. This at least tells me the problem isn't in the ecu or the tune. Anybody have any good suggestions on what else to try here?

 

Ok, I just got off the phone with a buddy of mine who has a d17 on the ems up in new york. He checked his pc and after 9 minutes of running, he had 6 timing errors. So, I suppose this is somewhat "good news". At least it means there isn't something wrong with my car that's causing these errors.

I had checked the plugs a few weeks ago and it looked like the number 4 cylinder was detonating (same cylinder that blew last time). I haven't been driving the car hard at all lately because my wideband wasn't working so I sent it in to PLX for repair, they should have it tomorrow and very hopefully I can get it back by the end of the week if I'm lucky.

I dono, I won't be able to tell anything until I get it back in. But the car would hesitate slightly when under boost a few days after the tuning.....