HI, fellow H-T members

i am writing this because i am having troubles with my motor. the issue i am having is during warm up or when i start the car, the motor turns over properly but when it goes to idels to warn up, the motor stalls out. it would not idle properly and sputter out. on my gauges like my AEM A/F meter it shows proper start at 14.4 but then creaps to 15.3 then jumps to 17.0 or --- lines saying i am to lean. you can hear the motor break up when this happens and when adding fuel to it by pressing pedal it still remains very lean unless i press pedal more then 3/4 way then i get a decent reading of 12.3-13.2 ratio.

i just replaced my spark plugs and cap n rotor today and problem still happens, this issue happened one day the next, but ive noticed when this did start that the day before was like in the 70's but now when the weather was below 60 degree this problem happened and has been ever since. I do not know what to do, but i am not a noob here at H-T. so please can any one help me.

here are my specs of my motor:

B18c Jdm Gsr
Sk2 intake manifold
70mm throttle body
420cc deatschwerks fuel injectors
full skunk2 valve train with high comp flat valves
Sk2 Pro2 cams with sk2 racing cam gears
Aris pistons 12:1 comp ratio
h-beam rods
stock crank for GSR
Hondata s300 ver2
AEM v2 hybrid CAI
Rpms 1320 Mega flow 4-1 megaphone headers
full 2.5 stainless exhaust with vibrant racing muffler

i think that is everything that would help in this issue:

the total compression is 12.2:1 in the motor and it was tuned for 93 octane gas. it has all new sensors and gaskets in the car and oil was just changed also, with spark plugs and dizzy components. please let me know if this is a tuning issue or something else and if it is tuning problem does any one know of a good tuner for all motor setup here in baltimore or in the baltimore-md reigion...

thank you.

 

Have you checked the fuel system? Sounds like it's losing pressure or not providing enough fuel to run it. Any CEL's?

 

no cels and i have full fuel pressure.... my pressure on my pressure gauge is reading 60psi

 

Go to your ECT fuel correction tables and try increasing the values.
Sounds like your ecu is taking away fuel trim as the car warms up.
But that shouldn't have changed from the original tune.
Id try logging your ECT and O2 sensors and see if anything looks abnormal.
If your running closed loop, there might be something in those settings as well.
But first, Id see if the original tuner is willing to look at it.

 

This right here this right here!!!!!!!

I have a similar problem some days that are warmer it idles and some colder days it takes a while before it holds idle, I think the outside temp has something to do with it. Seems everytime the weather changes usually colder i have this issue untill i retune the engine or the temp is warm enough outiside to whwere it starts or idles correct, sine we have warm weather and most likely the engine was tuned on a hot day colder days mess with the tune upon start up on my engine i think.

 

the iat tables may play a bigger role than the ect. with the fan and tstat working properly the ect will likely remain more constant than iat with bigger temperature variations

 

Lol, story of my life for the first 4 months, and I'm running pro1's If there degreed right it does not hold idle very well on warm-up. your AF's are always gonna be a little diff. on diff. days, I dont freak out on warmup its WOT and partial with load they should be in target areas. but anyways to fix it you have either tune cams for better vacuum or bump idle. I'm degreed per S2 mfg. with 44.5* overlap and idle is at 1000. The overlap just kills Idle characteristic, but dam do they come alive.

Btw if this is DD and on the east coast, seasons are gonna play a big role. You dont have a stock car anymore you dont get the luxury of a perfect idler Lol, I set aside 10 minutes in the morning every day to start and crack the TB for the first 30 sec's to hold idle until it will hold, it wont hold by itself until then. Before I went back into my S300 to bump it to 1000 it was worse cuz tuner had it set to 850. and if you think you can just crack the idle screw more to hold that wont work either cuz your ecu ultimately holds idle so it will just be fighting to keep it down which it will and then die anyways.

I have I guess a similar setup an ran into same problem, but heres mine, 11.5:1cr, pro1's, 420cc DW's (S300), 4-1 (2.5" Header back), S2 IM (74mmTB)
I gave the IACV a little more on the slider as well, If you have downloaded the S300manager and been in there a lil you'll kno. what I'm talkin about.
Idk if your S300 has the Bluetooth app capabilities or not but its a nice feature, you can check vacuum, timing, ECT, IAT, atleast that is what I have up on mine.
Atleast you'll kno if your vacuum is bad, if not then you can rule it out.

 

Retune for winter setup and have one for summer setup. Mine does this too when the weather changes but doesn't change that much off. Mayb like .5 from summer and winter changes on my aem wideband.

Fully warm ur car and adjust ur coolant setting. Look at ur coolant percentage corrections too on ur display. Also check ur iat correction percentage.

 

If that don't work then you might have to retune ur idle fuel and cruising fuel if ur wideband reads lean while driving. But then wot might be lean too. I've had countless hrs doin this on the road ( which I don't suggest ) but I like to learn things myself.

But mayb the best way is to let ur tuner retune for winter but save ur first setup for summer if it runs good in the summer.

 

I live in HI so weather is pretty constant. But there still some kinda cold mornings with either a little rain/humidity that I can tell give me a lil extra trouble then normal.

while on topic my car's Iat are normally at around 120F, but once I hit normal operating IATs Im already -1% on IAT corrections, is this normal?

 

just a quick update : had it taken at a new tuner and they did a great job, idles great and even unlocked some more power that i hadnt expected so im happy about it : took it up carlisle pa and had it tuned by Innovative Motorworks. awesome job they did worth the price and great people out there. if i ever had to tune again i would take it up there.

 

Good to hear!

 

Well what did it dyno!? You're kill me!

 

Im not a professional tuner but I work with cars and computers enough to say that seems just fine to me. Your almost at the zero correction factor at normal operating temp. The ECU is only deviating 1% from the baseline to achieve X air fuel ratio.
But on a sidenote, what kinda intake setup do you have? 120 seems kinda high, but maybe that's normal for HI. I did a little home made CAI and driving around on a mid 70's afternoon, I never saw more that 10-12 degrees above ambient. There's definitely power to be had in cold air!

When it gets cold again and acts up, check your a/f ratios and see if its obviously lean or rich. If it is, take note of the ambient air temp and adjust from there (or have your tuner)

 

Dyno graphs or it never happened!
Good people at IMW.