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00 ex d16z6swap y8intake p28 ecu custom roundbar frontend (workinprogress
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Discussion Starter · #1 ·
I have a fresh built d16z6 .5 mm overbore vitara pistons custom length rods new stock valves stock cam b16 throttle body z6 mani ported to match tb stock injectors a unknown racing header to 2.5 in exhaust and a demon v2 installed in a p28 tuning with Neptune rtp I think that covers it all anyway the issue I am having is I can start my car and it will idle for a few seconds between 13.5 to 14.3 on my aem wideband then just slowly goes full rich and nothing I do seems to stop it I have tried new plugs changing the timing up or down a few degrees and even pulled 35% overall trim from the fuel map and still it will always go rich I made sure the gague and sensor work properly can anyone give me an idea what to try next
 

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00 ex d16z6swap y8intake p28 ecu custom roundbar frontend (workinprogress
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Discussion Starter · #3 ·
Yes turned of closed loop set up o2 using the prelisted aem wideband and a new one I added idle screw is one thing I'm not sure about I'll have to check and get back to you on that one
 

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4d EG manual rack/trans low n slow
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Check Idle enrichment in Neptune, it's ECT based.
In HTS, probably Neptune also, there's a fuel correction for 2-3 other variables also, is the injectors you're using selected?
I'd also verify the wideband voltage values, my presets were not quite the same as what AEM sent with the wideband.
 

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00 ex d16z6swap y8intake p28 ecu custom roundbar frontend (workinprogress
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Discussion Starter · #7 ·
Was able to get it to idle 13.8 to 14.6 with what's in the pics but if left set it will still start to load up
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Idle was right afr seem right ECU and gauge reading the same
 

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93 Civic HB SI, 95 Civic HB CX
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Redo the tune. Reload the D16Z6 base map, then scale for your MAP, injectors and TPS.

DONT touch the main fuel table quite yet, only mess with the ECT fuel modifier table to get it to idle at the AFR you want.

Remember, the main table is the base that is used as reference across ALL ECT, IAT and other correction tables. If you mess with it first, it screws with the scalability across the modifier tables as the engine begins to warm up.

You've heard the saying "the base honda maps are a good starting point" im sure, this is why. The main fuel and ignition tables are what they are, AGAINST the ECT and IAT modifiers.

Leave the main tables alone, and only play with ECT correction modifier to get it to hit AFR as needed during warm up. Once its warm and at OT, THEN you can start to mess with the main tables.

Once the main tables have been messed with when warm, just remember you will likely have to retune the warm up running characteristics using the ECT and IAT modifier tables to redial AFR back in.

Also, make sure your battery and charging system is foundationally good, and if using aftermarket injectors make sure you have programmed in the injector offset calibration info so they operate as intended, at the voltages present.

This should get you where you need to go, so long as you understand what I'm trying to get at lol.
 

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4d EG manual rack/trans low n slow
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That's the base rom I'm using also, I had to dial the timing back a bit and tinker with fuel trim.
Right now mine does basically the opposite, a bit rich while warming, then trims out as it gets heat in it
 

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00 ex d16z6swap y8intake p28 ecu custom roundbar frontend (workinprogress
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Discussion Starter · #10 ·
Redo the tune. Reload the D16Z6 base map, then scale for your MAP, injectors and TPS.

DONT touch the main fuel table quite yet, only mess with the ECT fuel modifier table to get it to idle at the AFR you want.

Remember, the main table is the base that is used as reference across ALL ECT, IAT and other correction tables. If you mess with it first, it screws with the scalability across the modifier tables as the engine begins to warm up.

You've heard the saying "the base honda maps are a good starting point" im sure, this is why. The main fuel and ignition tables are what they are, AGAINST the ECT and IAT modifiers.

Leave the main tables alone, and only play with ECT correction modifier to get it to hit AFR as needed during warm up. Once its warm and at OT, THEN you can start to mess with the main tables.

Once the main tables have been messed with when warm, just remember you will likely have to retune the warm up running characteristics using the ECT and IAT modifier tables to redial AFR back in.

Also, make sure your battery and charging system is foundationally good, and if using aftermarket injectors make sure you have programmed in the injector offset calibration info so they operate as intended, at the voltages present.

This should get you where you need to go, so long as you understand what I'm trying to get at lol.
Yeah that makes sense and I know the tables your talking about so I'll give it a go when I get home in the am and thanks man I appreciate your help with this
 

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00 ex d16z6swap y8intake p28 ecu custom roundbar frontend (workinprogress
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Discussion Starter · #11 ·
Thanks everyone for all the help with this so far I have been able to get my afr where I need it at idle and as of now across most of the low cam fuel table using the ect and iat corrections to set afr at idle worked great then a couple small changes to the main fuel table and it's running nicely I do have another question when it comes to low cam ignition table mine starts of at 16.5 from 500 to 1500 rpm it's rough at idle and sounds like a slight knock but smooths out and is quite if I raise to 18.5 is that normal with a dropped C/R ?
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There's updated pics of the car still have a couple thing to finish up after the tune is done
 

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00 ex d16z6swap y8intake p28 ecu custom roundbar frontend (workinprogress
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Discussion Starter · #13 ·
Yes that's the first thing I do when starting a fresh motor aside from getting it to idle till it's at ot I locked timing in Neptune at 16 and I have a digital timing light with it set on 16 I lined up tdc mark on crank with timing notch on the timing cover and locked it down made sure it didn't move and since I have checked it three time and it's right could it be the piston slap I have read about that's something I have never heard and like I said I can go from 16.5 to 18.5 on timing table and the sound goes away I am using oem z6 plugs gapped to stock spec as well not sure if that matters
 

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93 4d lx, z6,ported, port matched, compression bumped, balanced, manual swap
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Sounds normal for it to want a degree or 2 on a low compression z6 build, though not for it to be making noise, what was the p to w clearance set at?
 

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00 ex d16z6swap y8intake p28 ecu custom roundbar frontend (workinprogress
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Discussion Starter · #17 ·
10w30 conventional oil and only if the rpms fluctuate it's doesnt over heat no coolant or oil leaks no smoke now that I have the idle afr right I'm fixing to do the first oil change later tonight or tomorrow it does have an adjustable cam gear which I don't like because it's not for a z6 just haven't bought a new one yet plan on a aem true time

Also going to pull valve cover and readjust valve lash
 

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93 4d lx, z6,ported, port matched, compression bumped, balanced, manual swap
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The aem is ok, but consider a golden eagle or something more robust if you ever intend on caming this motor even slightly more aggressive than stock.
 

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00 ex d16z6swap y8intake p28 ecu custom roundbar frontend (workinprogress
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Discussion Starter · #19 ·
Well it will be getting a cam when it gets boosted so I'll look into that thanks and I'm wondering after you asked what weight oil I'm running do you think maybe it needs a different weight oil I did notice that the sound does actually come and go
 

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93 4d lx, z6,ported, port matched, compression bumped, balanced, manual swap
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Where is Talon with that oil weight to bearing clearance chart? Im too lazy to look it up right now😅 proper oil weight is best determined by bearing clearance vs oil temp, somewhere on here the chart has been posted on some oil pressure thread.
 
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