Lumpy idle.
 

So, my idle is lumpy and very lean. My wideband(uego) often pegs lean during idle. I richened up the idle cells and it smoothed out a little bit but in order to richen it up, I had to change the VE idle cells to over 100% and my idle afrs were around 13ish. Anybody have any tips?

Thanks in advance,
Wes

Use the hi-res code if you're not already.

what size injectors? what's your timing at idle?

oh, shit sorry i thought it was in my sig. 460's. My msq is there, im not sure about the timing.

So, i flashed the HR code and it leaned everything to hell and back. I had to increase the entire VE table by 25% to make the damn thing drivable. I am still getting 14's under boost so thats no good. I drove my other car to work today and i will be working on it when i get home. I also have a random miss. I will be searching on problems with HR.

okay, either i suck ass at searching or other people are not having this problem. I flashed to the newest HR code and now i have a random misfire. It happens at all different times. I havent gone into boost because now, my boosted cells are untuned. I will log it when i get home.

Do you have the cap mod to eliminate noise/interference on the tach input? solder a .1µF capacitor between JS8 and Ground to act as a filter. This eliminates random misses and allows you to use Hi-Res code successfully.

As for going lean as fuck it happens to everyone when switching to high res, try scaling the whole table if you havn't already and make sure the req fuel value is correct for your 460's

I was REALLY hoping i wouldnt have to open up the mspnp.

http://www.radioshack.com/product/in...entPage=family

is that what i need?

Check for the revision letter under the MSPNP on the label - it may already have the cap mod. What revision do you have?

hmmm i bought it in august or september of '07 i know it was not long after it came out. I dont have the car with me here at work. Does the date of purchase tell you anything?

http://www.radioshack.com/product/in...entPage=family

oh, THATS what i need, right? (crosses fingers hoping the cap mod is already done)

Order Number: 14597
Detailed Invoice: https://www.diyautotune.com/catalog/...order_id=14597
Date Ordered: Tuesday 04 September, 2007

Oh, one more thing, How long is the warranty on the mspnp anyway? And would me doing the cap mod, void the warranty?

Thats the cap. I put that in and it solved all my misfire problems. Was and easy install.

Yes, that should work just fine(the second one) You could also send it back and have us do it. It would take a bit of turn around time though.

It won't void your warranty as long as the mod didn't cause the problem.

when did they start being made with the cap mod already done?

Jan 08. You ordered yours before then it looks like.

If you did want for us to do the mod, just send us an email, and we'll get you fixed right up.

yeah, i bought it in sept 07

Okay, i have not done the cap mod yet, it is coming. However, here is a log. The SecL DOES go back to 0 when i get the miss. Is this normal? (look at 214)

could be a issue with communications with the laptop if that's the case.

that would make the car miss and the tach cut out?

Just out of curiosity, what are your req fuel numbers in youe engine constants page?

If that figure is too low, you may have to richen your VE table loads to balace it out?

Req Fuel should be 6.7 for 460s on a 1.8 so according to the MSQ posted(req fuel 7.3) so he should be having the opposite problem actually.

This isn't your problem but I noticed in your AE settings you top entry for TPS base AE is wrong. You are telling the ECU when the rate of change of your TPS is 1 volt per second(pushing the gas pedal down relatively slow) to add 5ms of fuel injector opening time. Then the bottom entry is telling it to add .9ms at that rate. Change the top entry to 8.0 v/s, till you get around to tuning it. That's how it was set when you got it from DIY, must have hit a key when opening that page as that is the first cell the cursor would be in.



How warm was it the day you did these "lumpy idle" logs? I noticed your IATs are 94-96 degrees. If it was much cooler than that and your IATs are showing that high because of your sensor heat soaking that could be the cause. Try messing with Coolant-Related Air Density under the Advanced menu. Courtesy of Chad here are the settings I started with:

http://i28.tinypic.com/1z3xxjt.jpg http://i28.tinypic.com/k3ukgi.jpg

As air temps go up the density of the air goes down, IE the oxygen content of the air goes down. So to maintain a steady AFR fuel must also be reduced. The MS does that for you, it varies fuel based on air temp. That's all well and good until you start heatsoaking the IAT sensor and feeding the ECU incorrect data about the air actually going into the motor. The ecu thinks the air temps are higher so it leans out the fuel causing a lean issue. You can use the above settings to counter that at idle by telling it when the RPMs are below X and the air temps are Y add Z additional fuel.

BTW, that's a REALLY LOW idle MAP. 19kpa max? WTF. I idle in the 30s. You didn't block off your Idle Air controller, did you?

The IAC is not blocked off, maybe it is bad? My idle is really high as you can see. This is with the little idle screw (dont know the actual name) all the way tightened. I have a leak somewhere but i am pulling really good vacuum still which doesnt make sense to me. Thanks for taking the time to look at my msq. I am running HR code but i am going to go back to lo res until i can get the time to tune it correctly. I had a pretty ballin tune on low res and it is all fucked to shit with HR.