Need help with LS1/4L60e tune, bad idle

[LS-SWAPPER]

I know this has been covered in may different ways, and I've searched around but haven't found a fix. First off I need to say that I am still a novice especially when it comes to tuning with major engine changes. We are trying to get a friends LS1/4L60e going in his classic car (in other words this is a swap). It has a decent sized cam, headers and cold air intake. The MAF, throttle body and engine displacement are still stock. I have it running OK on the highway and during WOT but the idle is embarrassing. It starts up just fine and as long as I let it warm up completely it will drive, but if the ect is below 180*F it will die when put into gear. Once it is warmed up it will still stumble pretty dramatically when put into gear but it will recover. Even when its warmed up the idle still hunts for steady state for a while and then finally it will stick at 850 rpms like I have it set to do at the moment.

Like I said, this is my first time trying to tune a vehicle with a larger cam and I am pretty sure its what's causing my trouble. Can someone please take a look at the tune in progress that I have? Also attached is a datalog and the cam specs. I'm sure its an easy fix for you guys. Thanks!

[bimbleuk]

That cam looks like the one I've just installed. I've been using the tune in the first post below as a base for my tuning.

http://forum.efilive.com/showthread.php?14439-Idle-Tips-amp-Tricks

It's for a manual car so I can't help with specifc changes for an auto however that tune idled OK on my LS1 with the 222/224 cam. After doing a few CALC.VET runs to dial in the MAF and VE tables it's pretty good now. You may not have enough base air flow at idle at the mo. On my TB (80mm Edelbrock) I adjusted the idle bypass screw so that the Idle Control Valve sits at 50 steps at idle. I've seen 80 steps mentioned in the tutorials but it appears to work better around 50 steps on my car anyway.

Only annoying thing on my car now is a surging between 2-3% Throttle angle at low speeds which I need to work on but may not be helped by the slop in my transmission.

[gmperformancecentre]

give this a try

[EagleMark]

I know this has been covered in may different ways, and I've searched around but haven't found a fix. First off I need to say that I am still a novice especially when it comes to tuning with major engine changes. We are trying to get a friends LS1/4L60e going in his classic car (in other words this is a swap). It has a decent sized cam, headers and cold air intake. The MAF, throttle body and engine displacement are still stock. I have it running OK on the highway and during WOT but the idle is embarrassing. It starts up just fine and as long as I let it warm up completely it will drive, but if the ect is below 180*F it will die when put into gear. Once it is warmed up it will still stumble pretty dramatically when put into gear but it will recover. Even when its warmed up the idle still hunts for steady state for a while and then finally it will stick at 850 rpms like I have it set to do at the moment.

Like I said, this is my first time trying to tune a vehicle with a larger cam and I am pretty sure its what's causing my trouble. Can someone please take a look at the tune in progress that I have? Also attached is a datalog and the cam specs. I'm sure its an easy fix for you guys. Thanks!Something is wrong with how you adjusted your Main VE table, it's way off?

[LS-SWAPPER]

Thanks guys. Yes my VE table is off I'm sure, I was working on that when I had to quit. It's hard to tune the car when I can barely drive it around the parking lot. However, I don't think the VE is whats causing my issue but maybe I'm wrong. The reason I think that is because my idle issues are equally bad regardless of VE changes. In other words after I had started building the tune and it was still running the stock VE table, the dying when put into gear issue was just as bad as it is now. None of the VE changes I have made seem to affect this problem. One of the tables somewhere is changing the parameters of the tune when it is changed from P/N to reverse/drive. There are obviously a few different files that seem to play into this but I'm a little nervous to just start arbitrarily changing stuff.

On the other hand, I'm a little embarrassed to say I don't think the Calc.VET procedure went as planned. I'm almost positive it wasn't completed properly. Is my problem stemming from that??? Like I said though regardless of whether I was using stock parameters, Calc.VET attempts, and any other VE adjustments the dying issue while changing from P/N to a gear has pretty much remained unchanged. About the only thing I can do to alter it any is by changing the idle RPM settings and that has minimal effect.

For the record bimbleuk, I feel like this car would run fine if it was a standard trans. It runs great once its out on the road, and it idles decent...until the gear selector tells the computer that the shifter has been moved. And you might be right on the base air flow at idle issue. I know some people drill the throttle plate, other adjust the screw like you mentioned. What is the best way to tackle this?

By now everyone is probably worn out from my NOOBness! Sorry, and thank you!

[joecar]

AutoVE and Calc.VET are different... the latter is a more general case of AutoMAF.

[bimbleuk]

If there is a bypass screw then use that I think that on larger cams there may not be enough adjustment so they have to drill the hole bigger. You won't need to do that with this cam.

As mentioned the VE is all over so go back to a stock values or copy the VE table from the LS1 M6 tune I referenced. That'll certainly be closer than what you have now.

I only started myself this year and it took me a few weeks to get the maps setup correctly when logging and develop a suitable driving style plus route to correct the majority of the VE in a single drive.

[minytrker]

Thanks guys. Yes my VE table is off I'm sure, I was working on that when I had to quit. It's hard to tune the car when I can barely drive it around the parking lot. However, I don't think the VE is whats causing my issue but maybe I'm wrong. The reason I think that is because my idle issues are equally bad regardless of VE changes. In other words after I had started building the tune and it was still running the stock VE table, the dying when put into gear issue was just as bad as it is now. None of the VE changes I have made seem to affect this problem. One of the tables somewhere is changing the parameters of the tune when it is changed from P/N to reverse/drive. There are obviously a few different files that seem to play into this but I'm a little nervous to just start arbitrarily changing stuff.

On the other hand, I'm a little embarrassed to say I don't think the Calc.VET procedure went as planned. I'm almost positive it wasn't completed properly. Is my problem stemming from that??? Like I said though regardless of whether I was using stock parameters, Calc.VET attempts, and any other VE adjustments the dying issue while changing from P/N to a gear has pretty much remained unchanged. About the only thing I can do to alter it any is by changing the idle RPM settings and that has minimal effect.

For the record bimbleuk, I feel like this car would run fine if it was a standard trans. It runs great once its out on the road, and it idles decent...until the gear selector tells the computer that the shifter has been moved. And you might be right on the base air flow at idle issue. I know some people drill the throttle plate, other adjust the screw like you mentioned. What is the best way to tackle this?

By now everyone is probably worn out from my NOOBness! Sorry, and thank you!

Its already been said but your VE is definitely off and could cause it to run poorly.


If there is a bypass screw then use that I think that on larger cams there may not be enough adjustment so they have to drill the hole bigger. You won't need to do that with this cam.

As mentioned the VE is all over so go back to a stock values or copy the VE table from the LS1 M6 tune I referenced. That'll certainly be closer than what you have now.

I only started myself this year and it took me a few weeks to get the maps setup correctly when logging and develop a suitable driving style plus route to correct the majority of the VE in a single drive.

99.99% of the time you should never drill a hole in a throttle body.

[jstplyn331]

I have a few issues with my new setup, I had this tuned by a local guy that did this on my swap and it ran OK, but then we found out I needed to go bigger.....:0) You know due to bad rings.

So know it is a 383 LS1 with a 4l60e and I am having a hard time ideling. I am not sure the guy that tuned it the first time was at all very good anyway, So I bought a V2 and thought I would give it a go.

Along with the motor build we also did headman header long tubes 3" exhaust. Same cam as it was big and would still work.

here is my file, but not sure what to change and or if it was even correct in the begining. any help would be much appreciated and thank you in advance.

[joecar]

More info (year/model/vehicle, any other mods, FPR...)...?

Log files...?

[jstplyn331]

Below

[jstplyn331]

OK Here we go this is all the info received from the mechanics that built the motor.
Was a LS1 4L60e out of a 2001 Camaro @ 9.6:1 Compression
It is now a LS1 383 with the 4L60e put into a 1967 C10 Truck

Have original Intake and Heads, but we ported the Intake and exhaust

Has Magic Stick 4 Cam

Texas Speed 383 Kit
Duration is at 50 thousands

Intake 239 Exhaust 242

Cam Lift
Intake 649 Exhaust 609

Lob is Center at 111 thousands

All Springs and Push rods to match

billet Comp Timing Set in at 0 Degrees

The 4L60e has all good internals on rebuild Corvette servo and YANK converter with 3,000 stall

I hope this helps have not done any Data Logging yet, but if you tell me how to do it I will get this done ASAP.
Once again thanks in advance.

[limited cv8r]

In your log, your TPS is almost never zero or close to it at idle. So most of the time you will still be using your main spark tables,even at idle. If you look at table B5916 its value is 1.19. You need your TPS to be below this and B5917 for the PCM to use the base spark tables. You may need to do a TPS relearn or adjust your throttle for this to happen. You can raise B5916 if you cant get the TPS as low as you need. Also in your first post you say you still have the MAF, if so, why are you tuning the VE table? Not the MAF? I've attached your tune with the spark table numbers a bit closer together which may help it from hunting as much.
Could you include GM.DYNCYLAIR in your logs, also what are your fuel trims doing?

[joecar]

I missed his log file, I didn't see it...

[limited cv8r]

First post

[jstplyn331]

Thanks Limited, I will give that a try do a data log. I just got called out of town for a few days so I should be able to get that done this weekend

[joecar]

First postAll I see is a .ctz file...?

[jstplyn331]

Have not done any data logs if that's what you mean? I will try this weekend. Is there anything specific I should log

[limited cv8r]

AutoVE3.efi, in first post??

[jstplyn331]

That File is not mine, that is LS-Swappers, is that the file you went off of for the file you did re calibrations on?

[limited cv8r]

Whoops, my bad. Yeah I did the wrong file.
What are the problems you are having with your idle?

[jstplyn331]

It will start just fine, and then when I give it gas it goes very low and drops down sometime dies, It also will die if I kick the A/C on, I do not have a wire from the A/C to the computer so I was trying to compensate the idle, if that is not a good way of doing it I can run the wire.

[limited cv8r]

Try this. I added some spark to your idle underspeed which was all zero's after about 200rpm error.

[jstplyn331]

Try this. I added some spark to your idle underspeed which was all zero's after about 200rpm error.

OK I loaded this file and went on a drive did a few pulls on the throttle, not sure I did a Data Log correct, but I did not see any other way to do it.

Let me know what you think, but as of now it was much better. Thanks. I could even run the A/C and it did not fall on its face.

Is adding some spark advancing the timing?

[limited cv8r]

It does add timing, but only to help your car from stalling, depending on the RPM error from desired idle speed. I did make a few other changes. If you do a compare between your file you uploaded and the modified one you will be able to see what was modified.
Glad it helped you.

[jstplyn331]

It does add timing, but only to help your car from stalling, depending on the RPM error from desired idle speed. I did make a few other changes. If you do a compare between your file you uploaded and the modified one you will be able to see what was modified.
Glad it helped you.

Did that Log file tell you anything? I am not sure how that works, I hit play and can watch the Dashboard.

[limited cv8r]

That log file doesn't look too bad. A quick read of the scan tool PDF will help you understand viewing your logs better and how to use the different dash page.

[jstplyn331]

Did not know there was one, I will take a look thanks for the info