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Old 04-15-2013, 11:40 PM   #1
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Default Unstable idle with new injectors

MSM
ID 1000
Reverant built MS2 Enhanced

Just upgraded to some ID 1000 injectors and having some problems getting a stable idle. Once up to temp there's a full point AFR swing as the idle oscillates by 100-150 RPM. Also getting a vibration that kinda sounds like a misfire that gets much worse with a little bit of throttle - TPS of 1-3%. Vibration might be the wrong word...the whole car shakes.

Two logs attached. The first is from a cold start and includes me trying to get idle AFRs in check - I had it idling rich to see if that would help (it didn't). That one runs until TS went offline when I set the laptop down. The second log has a couple throttle inputs.

Sorry, I had to zip the first log in order to attach even though it is smaller than the max allowed .msl


2013-04-15_20.18.33.msl.zip

2013-04-15_20.41.44.msl

CurrentTune.msq
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Old 04-16-2013, 01:37 AM   #2
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check for vacuum leaks around the new injectors ???
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Old 04-16-2013, 09:50 AM   #3
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did you change your deadtimes? did you change your req_fuel? did you retuen fuel sinec EV14 injectors spray fuel much differently than others? what did you have before? do you like supressing information to make it hard for us to help you?
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Old 04-16-2013, 10:38 AM   #4
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did you change your deadtimes?
yes. if it matters, I never changed it from the basemap on the old injectors.
1.0 -> 1.228

did you change your req_fuel?
yes
9.8 -> 4.8

did you retuen fuel?
idle, yes. parts of the map are still on old injector values

what did you have before?
MSM MS2 Enhanced_2012-10-10_19.57.56.msq

do you like supressing information to make it hard for us to help you?
yes

I gave up trying to tune rest of the map until idle was worked out. It pulls nice and strong but backfires like crazy on overrun.
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Old 04-16-2013, 09:30 PM   #5
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Quote:
Originally Posted by Gt2560rMiata View Post
check for vacuum leaks around the new injectors ???
It's a good thing I'm not a mechanic...none of my customers would come back after spending hours trying to fix what's not broken and ignoring the real problem. Didn't notice any changes with a propane torch, but a bit of carb cleaner shot onto #4 made a noticeable difference to the idle speed for a couple seconds. Thanks for the tip Gt!

Can a mod move this to the correct section?
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Old 04-17-2013, 01:17 AM   #6
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not sure how i managed to do this, but it might have something to do with the vacuum leak.
Unstable idle with new injectors-img_20130416_201238.jpg
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Old 04-17-2013, 02:58 AM   #7
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no prb. did you use plenty of lube when you installed them ? im assuming the oring was a new one that came with the injectors ?
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Old 04-20-2013, 02:42 PM   #8
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Car is running much better now with a fresh set of Denso cushions and no vacuum leaks. This is what happens when someone who doesn't know what they are doing buys used parts. The injectors came with 14mm green o-rings installed along with a plastic tip kind of thing and that's how I installed them. And that's why I had a vacuum leak. So I ordered a set of Denso cushions and a new set of o-rings thinking the cushion was the plastic piece. It's not. The cushion is what everyone else refers to as an o-ring and was all I needed.

My tune was all buggered up from the improper installation, going rich to lean to rich at a couple RPM ranges. Still a lot of work to be done but it's at least running decently now.
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