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Idle tuning for automatic transmission

Posted: Fri May 06, 2011 7:28 pm
by V8hilux
I am having some problems with the idle.

When i put the car in gear, the idle drops from 800 to about 600 and is like a sparkplug lead falls off.
The IAC tries to bring it back but it takes forever for it to step up. Is there a setting to make the IAC motor go up faster?

I just took a log with starting car, idle for a few seconds..then put in drive, revs drop car shakes and the iac slowly maxxes out but cant get the revs back to 800. then i pull it out of gear and give a quick rev.

any ideas?
startidleputingearrevsdropcar shakes.xdl
(66.94 KiB) Downloaded 364 times
and heres a longer one when i went for a drive to get a log to do the ve tables
the car was fairly gutless.??
firstdrive383.xdl
(452.77 KiB) Downloaded 417 times
thanks.

Re: Idle tuning for automatic transmission

Posted: Fri May 06, 2011 8:13 pm
by VL400
Looks like the IAC is not working and you have a code 35 because of it.

Re: Idle tuning for automatic transmission

Posted: Sat May 07, 2011 1:41 pm
by V8hilux
I think I may have found the problem..... :roll: :roll: :roll:

I gets out this morning and started pulling plug leads to see if i had a misfire.

Pulls number 8 off... engine still running the same,
pulls number 6 off... engine still running same,
pulls number 4 off... engine stumbles slightly more.

WTF,

I've been driving around on 5.5 cylinders.. still spinning wheels on the dirt road but definitely feel the lack of power.

I tested all the leads and they averaged between 3-6000 ohms but number 4 had 50,000,000 ohms :o

I pulled all the plugs and the 5.5 that was working were black as boots.

So it appears the wideband would have been reading lean because of the 2.5 cylinders feeding in clean air to the exhaust and the other 5.5 running extra extra rich to to get the wideband where i wanted it.

My guess is that this might be because I am running higher compression now I don't know (used the old plugs/leads) but number 8,6, were oily wet and yuck.

Will burn into town and grab some new plugs and a lead and see what happens.

Re: Idle tuning for automatic transmission

Posted: Sat May 07, 2011 3:29 pm
by V8hilux
YEEE HAAA :thumbup:

I'm in business now!!!

The car started instantantee. But now she is rich as buggery. Now that she's burning on all pots and not sending fresh air up the muffler.

evn though i just started it, it is rich as heck but even so, revs like a beauty, put in gear, motor doesnt even know. yee haa.

The bad part is that I have already burnt 125 bucks worth of juice trying to tune it on 5.5 cylinders.

Ah well,

I might get somewhere now.

The problem was that I broke 2 plugs pulling them out a when I blew it up before and just grabed 2 old ones from my nuts and bolts bucket and chucked em in. Shee Revs NOW!!!.

ha ha

thanks guys.

Re: Idle tuning for automatic transmission

Posted: Sat May 07, 2011 4:31 pm
by The1
nothing like upgrading from a V6 to a V8 hey lol

Re: Idle tuning for automatic transmission

Posted: Sat May 07, 2011 6:08 pm
by Holden202T
i've found it doesn't take too long running pig rich to foul plugs so get the tune dialed in asap!

Re: Idle tuning for automatic transmission

Posted: Sat May 07, 2011 6:49 pm
by antus
Yep, you have to make sure everything is mechanically good before you start tuning! Otherwise as you know you just end up chasing your tail and wasting time and $.

Re: Idle tuning for automatic transmission

Posted: Sat May 07, 2011 6:51 pm
by V8hilux
I went for a drive and logged it, came home and altered the ve table and seems to be running nice, It was soo easy when all pots were running, I wasn't chasing intermitent things.

I still think there is some more in it if I up the timing. The timing map is just the one that came in the ose12pv111 and looks a bit weird the way it jumps all over the place.

Overall very happy with todays progress. I will go for another spin tomorrow and get another log and see how it looks.

I see in the flags the lean cruise option, I'd be interested in setting that up. What is the usual fuel ratio in the lean cruise mode.
I see the table for it and just looks like it works in a few cells but don't know what the numbers in those cells mean. Is that the amount of % it leans those cells by or does it take a few AFR out and go like 17:1 or something?

Thanks

Re: Idle tuning for automatic transmission

Posted: Sat May 07, 2011 6:56 pm
by V8hilux
I didn't cotton on to the plugs till today, I was blaming the tune and the brand new (big twin throttle manifold) thinking it may of been making lose torque low down.

I did do a quick finger on the pipes test and they felt hot every time. must of been only fining every now and then.
If I had a infra red thermomoter I probably would have picked it straight away by looking at the exhaust temps.

Makes a big differencs when she runs on all 8

Re: Idle tuning for automatic transmission

Posted: Sat May 07, 2011 7:03 pm
by antus
The stock ose12p timing maps are holen maps, and while they may not be perfect for your engine, they are right for the factory engines they came out for.