As many of you know I have lots of mods. Intake, Intercooler pipes, IC, Sheetmetal intake, 272 cams, GT35R turbo, Tubular header, injectors (780cc), fuel pump, fuel regulator, etc...

I used the global adjustment on the OL Throttle to adjust for the injectors and the car now seems to run good... added some fuel up top to get it just right and now the car idles like it did before with the AFC. My question is how to get it to idle well

I have seen some people lock thier timing around 20 degrees at idle. Any guesses on how to make mine idle better... more fuel at idle than normal, less fuel than normal... 0 degrees of timing, 5, 10, 20? I have no idea... Any help on the idle would be appreciated.

Today I will try to screw with a few things but I would like to know what other people have done to help it out.

 

More fuel at idle will improve things, unfortunately with closed loop fuel control at idle and part throttle, it will adjust, your best bet is to look at your fuel trims, and try to get them within +/-10% That will do the most to improve your idle.

I don't recommend locking the timing in the 0% column, the ECU adjusts timing for different loads on the engine.

The two things that have th most impact is to raise your Idle RPM's so your fuel injectors arent battling 'dead time' and your building more vacuum at idle at a slightly higher RPM, and getting your fuel trims in check.

You'll never get a perfectly smooth idle until we get idle control features on the UTEC such as cas bump and sub-injector duty (dead time idle compensation), tip-in enrichment, Low-MAF clamp value, and BISS target idle speed controls..

 

I have the best luck tuning cars to around 10 degres at the idle rpm with bigger turbos. This is on a EMS but doing this really does help stabilize things during idle and during idle return. Give it a shot on the utec and see if it improves.

 

It certainly can't hurt things... If you look at your timing at idle, it varies from 5 degrees to 12 degrees depending on "load" like the alternator or A/C compressor..

 

I second that. I had Autronic before and I ran it at 10 deg. FWIW, my car idles at 3-7 deg in stock form.

 

Yeah mine stock is anywhere from 0 to 12... I locked it at everything from 5 to 20 and it seems to make it idle much smoother but the car still has a huge problem "catching" the idle... like once it idles its great but getting it to start idling it has issues. Any ideas on that one?

 

The Load/RPM Cells next to idle cell are all a similar timing value as well correct? For example if you are idling at 900rpm and it is set to ign of 10 , the next point is set to what? Probably ign value of 12.5 or so that everything ramps up smoothly and not too fast correct? Also how does the fuel look when it comes back to idle?

 

Also look at your MAF reading at idle, its possible your airflow rate is very low so idle speed drops and it can't catch itself because the MAF reading is getting disrupted.. If you can manage to log it happening, post the section of the data.. It might give me some insight to whats happening.

 

ok I will get a log of it and post it up

 

TrinaBabe,

So did you find a fix to your idle problem?

 

Nope :P

I just have it running stock timing and plus about 4 percent of fuel and it does... ok.

Doesnt catch the idle well but once it does it normally idles decently... it sometimes will go real lean and then real rich for a few seconds then re-catch. Im more concerned with tuning other areas at the moment. Ill get to it though

 

Out of curiosity, what plugs are you running? I found when I had colder plugs with a fairly large gap, the car would idle poorly and would periodically do that. I also noticed when my fuel trims were outside the +/-10% and idle maf readings were outside of the 30-40hz window, the car would do exactly what your describing. Oh yeah, I discovered that after I upgraded my ignition, my idle got much smoother than it was before (I don't have cams, but it may help)

Another silly thought is that your O2 sensor may be fouled due to the race gas..

 

I have thought about the 02 sensor being junk.. I have ran alot of race gas through it and i have around 16k miles now. I will change it out if it seems to act funny next time I log with a obd logger.

The plugs I have ran with it while it was acting funny were both stock plugs (Slightly fouled) and BR8ES but the gaps have always been stockish. Normally the idle hertz are around 40-50... I guess i will try to make them a little lower and see if it helps.

What ignition are you running? I was thinking to buy the MSD-DIS2 for two big reasons... one, it is pretty cheap compared to a coil on plug design, lets you adjust a few things like timing retard and rev limiters and the other reason is I know it can handle the power I will eventually run. It held John Shepherds car running 8's for a long time so I am sure it will handle my baby little guy

 

Run the bpr8es. THe one with the "P".

 

I really like the MSD-DIS2 It has alot of features that you probably will never end up using on the Evo.. And it makes adding a COP setup easier (Check out the Buschur second generation Evo COP setup, fits under the plug cover)

I built a COP setup utilizing a DSM Ignitor, Honda motorcycle coils, and a MOTEC CDI-2 (http://www.motec.com/products/cdi/cdi_2-specs.htm) The motec unit is expensive unfortunately.. I removed and went back to stock a few months back because I was waiting to find the correct AMP part numbers for the connectors to correctly interface it with the stock ignition without using a cobbled together connector that would frequently fall off on my car.

A few weeks back I bought an HKS-DLI2 with the plug and play harness, I ordered it to get my hands on the harness to get the connector part numbers off it.. Turns out the harness alone is only $39 and I suggest anyone building a COP setup who wants plug and play, just order the harness and steal the connectors off it.

ANYWAY, I was going to post a full review on the HKS DLI-2 on monday, so keep your eyes open for the real review, but my short answer is the DLI2 ended up working just as well as the COP setup I was running, It boosts the voltage to the coils slightly, and can trigger the stock ignitors several times in a row correctly through its CDI Features. On my car, the older fouled Denso IW24s were missing frequently and would get spark quench at higher boost and under higher RPM operation, the HKS completely eliminated all misfire at idle, throttle response was improved, it was less prone to stalling when driving around and doing very low RPM rolls out of a stop light.. Any misfire I had previously at higher RPM was completely gone. I'll probably keep it on the car for awhile... Plus $500 you can't beat for a completely plug and play setup that took 15 minutes to install. I want to do some research on how it "Retriggers" the stock coils to see if I can just replace the coils with the COP pack I made, the reason I want to do this is because the HKS unit is TINY, It makes more sense to take a DSM ignitor and use individual coils (such as the buschur COP setup) with the tiny HKS setup...