Another Idle problem

[kostelacd69]

like it states I have another idle problem. Ive been in Iraq for 4 months and just went home for two weeks. In that two weeks I pull my lq9 402 out took out the piece of shit total seals that were 2000 miles old and useing 1qt / 100 miles. Put my hellfires in put the motor back in, installed PCV (ford turbo one), installed the oil seperator, and then installed my new gt4508r. Got it all runing and tune pretty close but its doing some wierd stuff. It seems like everytime I look at the afr at idle I have to keep adding or taking away 2 to 3 %. Anyways the real problem is the fact that when I go to back it in the drive way it starts this surging crap and then will sometimes stall. I am now back in Iraq but I will add the tune file. Maybe one of you BA's can show me up here lol. I changed alot of crap and not sure if I should have or not. So if someone is bored and can help me out that would be great.

[odd boy]

try this file.by ODD.tun

[kostelacd69]

Well the only thing is, is that I have a COS3 speed density so I no longer use the MAF. The Desired airflow numbers are what my idle scan came up with. I started with the truck stone cold then watched and adjusted all the way up. Once it was at op temp I let it idle and record to give me an avage in Park and then again in gear.

[kostelacd69]

I guess I need to figure out what I shut off like a/c idle stuff and the adding of air for steering or breaks and then turn it all back on. maybe thats whats wong

[DrkPhx]

It could be a few different parameters (or a combination) causing the problem. Can you post a log when it surges?

[kostelacd69]

I wish I coould post a log but I but have any and Im no longer in the states to record one. Sorry

[DrkPhx]

I have some questions:

- Curious why you have B3601 set to 15.52?
- What are the cam specs?
- Do you have a large stall converter (assuming this is a auto)?
- Do you use a WB to tune? If so what is the AFR at idle?

It's hard to really pinpoint the cause without at least looking at a log, but there are some basic tips to help. First, I would recommend reading the idle tuning tutorials in the stickys on this board. They provide excellent information. Here's a good one: http://forum.efilive.com/showthread....ul-Info-Inside

- Looking at your VE table it appears you did the Auto VE to tune. If so, I would recommend using the filters to remove the cells that are hit infrequently and keep using the Auto VE to remove the giant spikes and fill in some of the valleys.
- The spark values in the idle region (0-1200 rpms x .08-.32 gms/cyl) of the spark tables should the same or very close.
- The idle airflow values in the warmer temps seem high for a 650 rpm idle, but if works, it works. Depending on the cam, I would consider bumping the idle rpms 25-50 rpms to see if that helps.
- Use the DVT/bi directional controls on the scan tool which allow for real time (but not permanent) adjustments for the AFR, spark, IAC and RPM parameters. These go a long way to remove the guess work from idle tuning.

[kostelacd69]

I have that set that way becuase I was trying out useing the wideband as a narrowband and programing the switch voltages .500@15.5:1. I just never changed it back. cam is 600/600 .226/.230 115lsa+1 degree. some what small. 2800 rpm converter. yes I use the wb to tune. AFR at idle are 15 to 1. I never had an idle problem till I added all that stuff and did all that work. Youve got me confused in the last part there. DVT/ bi directional controls????? Not sure I know what your talking about there.

[DrkPhx]

I never had an idle problem till I added all that stuff and did all that work

Are you referring to the engine rebuild, new turbo or tuning changes?

Youve got me confused in the last part there. DVT/ bi directional controls????? Not sure I know what your talking about there.

There's a tab in Scan Tool (DVT) that is mostly used for trouble shooting and diagnostics. In the DVT tab, there is a a sub tab call engine controls. In there you can manually adjust certain parameters, like spark advance, idle rpm, idle IAC, commanded AFR, etc with the vehicle running.

In your case, it sounds like the surging is isolated to Reverse only. If true, then it should be relatively easy to fix, but you need to pin point the conditions. Does it happen at a specific ECT, is the AC on, are the fans on? The DVT controls can allow you to do that with the vehicle in Reverse. It sounds more complicated than it really is. Hope this helps.

[kostelacd69]

Ok yeah I know what that is I just Spaced it when you said it. This started after the motor came out of it and put back in. I know think about it and everything was added the day before I did the engine and I dont remember this problem. Im sure its just something stupid like the air flow is to high or low. I did note that it did it at op temp with everything off and never tried it with everything on. I play with it more when I get home. Thanks for all your help.