Torque Converter lock-up correction?

[ctrlraven]

Since I got an updated tune to work with my PI 3500 I have noticed that my torque converter will lock up at light throttle while going 40mph in 3rd gear, is this normal? I guess because of it locking up at that speed has been causing my "dead zone" from 40mph to 65/70mph. Quite a few times I have needed to punch it coming off an off-ramp to merge into traffic and the car just goes no where faster and bogs down and I have noticed slower 1/4 mile times. From a dead stop at WOT it pulls hard until around 40 mph, bogs down and then once I get past 65/70mph it starts pulling hard again. I thought with a higher stall converter I wouldn't notice any difference until I got on the gas, at least that is what I have read off here.

Dennis, if I send you the last tune file you sent me could you take a look at it and see what's going on with it?

Thanks,

Chris

[ITLRUN]

If you have access to SCT software and an X Cal 2, data log it to see where ererything is. It sounds to me that it's either in your fuel table or timing tables. ITLRUN Or you could put it on a dyno and check it that way, by trying to recreate the same conditions.

[burt ragio]

I have the sct xcal2. If I want to see what is in my tune I assume I must 1st take the tune back out of the car then data log info to www.sctflash.com (http://www.sctflash.com) ?

[duhtroll]

You cannot "take" a tune from a tuner unless it's to load it into your MM, to my knowledge. You can load one into the tuner and keep a copy on your CPU if you like. Modify the copy as you see fit with the editing software (if you purchased it) and then reload it into the tuner. Keep every file with a different name and date them.

Mine is doing some funky TC lockup things too. The TC normally acts like an engine brake when in OD and coasting down a hill or off ramp, which is getting very noticeable. I think mine was set to something like 16 seconds and if I would retouch the throttle after coasting for a bit, the car would lurch forward as if dropping back into gear.

Add running the AC and everything gets even worse -- it just doesn't run very smoothly. I still have the aforementioned cleaning of my MAF to do tomorrow (as it will be the first time I can get to it in a couple weeks).

I am seriously considering setting the lockup after release of the throttle to zero, thus allowing smoother coasting.

TMF graciously has helped edit my tunes since he has the mad skeelz and software. We were talking about positives and negatives to setting the lockup to zero (seconds).

Can anyone see a real reason to not keep the TC unlocked when coasting, other than the rev bouncing it does as a result?

[Dennis Reinhart]

You can call me Monday I will try and help I am leaving Tuesday for Indiana

[Tom Doan]

OY, same thing here, mine hits at 43 mph, I'm running a 1800 stall with 4 plates, I love it but as time goes on it needs a little love from Dennis to keep me tight. I love Jacksonville in the winter.Tom

[Motorhead350]

I think I have the same exact problem.

[Dennis Reinhart]

I think I have the same exact problem.



I am convinced it is in the transmission, it has over a 100K on it, and after driving the car I was able to break the tires loose by power braking it, but it will not come loose at a dead stop, even at WOT the transmission on the 1/2 is a VERY VERY soft shift, even after maxing out the 1/2 line pressure, any other car would be chirping or breaking the tires loose with a SC. My advice is to pull the pan look for metal and check the 1/2 accumulator, the converter is less than a year old PI will check it for free, and this would be a must if they find the trans is en-deed damaged, the converter holds over 8 quarts of fluid so you do not want that contaminated fluid circulating back through a rebuilt transmission and you should always flush the cooler as well.

[ctrlraven]

Dennis will you be around the shop this week?

[Motorhead350]

I'll have it checked and keep everyone posted.

[Zack]

Dom, just drive it as is and get the axle fixed.
Your trans is tired and is noticeably different since I drove it last time.

[Dennis Reinhart]

Dennis will you be around the shop this week?
I will be home tomorrow

[Motorhead350]

Your trans is tired and is noticeably different since I drove it last time.

Just because it doesn't shift as hard doesn't mean it's tired I believe. It has a different tune now so it doesn't do that anymore.

[MarauderSM]

Just an answer please. When is the best time to have the TC lock up on a supercharged Marauder? A does it lock up in overdrive only?