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Old 05-24-2015, 07:11 PM   #1
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Default MS3 - Lean start, idle, sync fault


I have now put a couple hundred miles on my newly VVT swapped 95 with Rev MS3 Basic and have some questions, as this is my first time fiddling with tuning.

Lean on start - regardless of temperature, it seems to be lean when I start for maybe a minute or so before acting normal. My intake is the entire stock 95 intake except for the top half of the '02 airbox (has a hole for the IAT to sit in). I was thinking it could be heat soak, but the MAT doesn't change much between starting and acting normal (maybe 125 to 118 degrees F). It has happened when the car is fully warm (180+ coolant temp) and cold. Could the hot restart be heat soak, and the cold start be fixed with WUE?

Occasional high idle - This problem is strange. It only happens occasionally, but the car will want to idle high enough that it hits over-run fuel cut, causing an annoying wandering idle. If it's doing this and I shut off the over-run fuel cut, the idle will settle down to normal in maybe 10 seconds. I can't figure out what's causing this.

Sync fault - I'm thinking this might be related to the above problem, but since I hooked up my tach I see SYNC FAULT in Tuner Studio. I did this by cutting the wire that originally went to the ECU harness and splicing it into the db37 pin 10 (so now nothing goes into the ECU there). Should I have made a junction there instead (i.e. so the tach wire goes to db37 and the ecu?).

I've attached my tune file - unfortunately the only log of the weird idle I have is a few seconds long (not sure why it stopped). I've attached one of some regular driving this morning here . My VE table has been arrived at strictly through autotune - I haven't messed with it much manually. The only other changes I've made from Rev's base map are the EGO correction authority, WUE and I tried playing a little with the ASE because it seems to "sputter" to life instead of "jumping" to life like an OE tune would (it still sputters).

Attached Files
File Type: msl 2015-05-24_15-47-28.msl (104.7 KB, 37 views)
File Type: msq CurrentTune.msq (223.8 KB, 56 views)

Last edited by Uncle Humjaba; 05-24-2015 at 08:09 PM.
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Old 05-28-2015, 07:40 PM   #2
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No comments from the peanut gallery?

I think the sync fault might be some weird TS bug, because I see "sync fault" in two locations and it's only red in one of them. It stays red even if the ECU is off/disconnected.
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Old 06-01-2015, 02:42 PM   #3
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I think I have the same issue as well. I have a slight knock at idle and have difficultly holding idle after start. Problem would be gone if I hold the rpm for a few seconds though.

I don't always see sync fault but it has been happening a bit more often
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Old 06-01-2015, 06:30 PM   #4
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For the high idle, try using the basic mode, I see you have it in advance, but try it in basic mode first and see how your idle is.

Also, for lean on start, I would go to your MAT Correction table, and zero it all out (put it at a hundred the whole way through), and see if that makes a difference. Also in your logs, take a look at GAIR (I believe that is right) and that shows your MAT correction value.

You know if it's an issue with heat soak by putting up a gauge for it on TS.
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