Lock-up intermittent at highway speeds...
Thread Starter
Joined: Nov 2005
Posts: 2,874
Likes: 314
From: Baltimore County, MD.
Lock-up intermittent at highway speeds... ...but seems to be fine at lower speeds.
Took my car for a nice highway drive today, but noticed that it wasn't "holding" in lockup when at 65-80mph and at light throttle. At 45-55mph it seems to work, and hold, in lockup normally.
When it would lockup, it might stay locked up for a few minutes or so, then for whatever reason, unlock and stay unlocked for several minutes. This was on flat road at steady speeds.
It acted like this when I first installed camshaft, due to misfire code, but I get no codes. Back then, problem was also very intermittent and pretty much locked or unlocked whenever it damn well pleased...After tuning, it was fine until recently, with today being very noticeable. FWIW, car shifts the same as it ever has, and I notice no other things different when driving.
Is it possible that it still needs tweaking of the misfire tables?
Does ambient temperature have anything to do with this?
It seems that it has only done this since it has gotten cold out.
Any ideas?
Took my car for a nice highway drive today, but noticed that it wasn't "holding" in lockup when at 65-80mph and at light throttle. At 45-55mph it seems to work, and hold, in lockup normally.
When it would lockup, it might stay locked up for a few minutes or so, then for whatever reason, unlock and stay unlocked for several minutes. This was on flat road at steady speeds.
It acted like this when I first installed camshaft, due to misfire code, but I get no codes. Back then, problem was also very intermittent and pretty much locked or unlocked whenever it damn well pleased...After tuning, it was fine until recently, with today being very noticeable. FWIW, car shifts the same as it ever has, and I notice no other things different when driving.
Is it possible that it still needs tweaking of the misfire tables?
Does ambient temperature have anything to do with this?
It seems that it has only done this since it has gotten cold out.
Any ideas?
FormerVendor
Joined: Oct 2006
Posts: 3,123
Likes: 3
From: D-F/W
It is highly possible for this to be relarted to your tune.
My recommendation would be to Log the transmission PIDs while driving in order to determine why L/U is being inhibited.
Also, what is the fluid condition?
What converter are you running?
How long has this combination been together?
Any changes to the car at all prior to the symptoms?
Go Cowboys!
g
My recommendation would be to Log the transmission PIDs while driving in order to determine why L/U is being inhibited.
Also, what is the fluid condition?
What converter are you running?
How long has this combination been together?
Any changes to the car at all prior to the symptoms?
Go Cowboys!
g
Thread Starter
Joined: Nov 2005
Posts: 2,874
Likes: 314
From: Baltimore County, MD.
It is highly possible for this to be relarted to your tune.
My recommendation would be to Log the transmission PIDs while driving in order to determine why L/U is being inhibited.
Also, what is the fluid condition?
What converter are you running?
How long has this combination been together?
Any changes to the car at all prior to the symptoms?
Go Cowboys!
g
My recommendation would be to Log the transmission PIDs while driving in order to determine why L/U is being inhibited.
Also, what is the fluid condition?
What converter are you running?
How long has this combination been together?
Any changes to the car at all prior to the symptoms?
Go Cowboys!
g
Converter is PI Vigilante 3600 stall.
Been in the same configuration (converter-wise) for nearly 5 months. Cam added about 4 months ago and re-tuned right after camswap.
No tune changes. Only change was me adding a free flowing single in/single out catback to replace the stocker. Everything else is as it has been for 3-4 months.
Is it possible that the transmission is actually running "too cool" and messing with lockup? I do not have fluid going through the radiator, just through the big aftermarket cooler in front of the radiator. I only ask that because it seems to work fine at slower speeds where there isn't as much cold air going through cooler. Just a thought?
FormerVendor
Joined: Oct 2006
Posts: 3,123
Likes: 3
From: D-F/W
Fluid "looks" fine, has the nice red/pink color, and doesn't smell.
Converter is PI Vigilante 3600 stall.
Converter is PI Vigilante 3600 stall.
Been in the same configuration (converter-wise) for nearly 5 months. Cam added about 4 months ago and re-tuned right after camswap.
No tune changes. Only change was me adding a free flowing single in/single out catback to replace the stocker. Everything else is as it has been for 3-4 months.
No tune changes. Only change was me adding a free flowing single in/single out catback to replace the stocker. Everything else is as it has been for 3-4 months.
Which takes me back to my Logging comments... let's get some useable data.
Is it possible that the transmission is actually running "too cool" and messing with lockup? I do not have fluid going through the radiator, just through the big aftermarket cooler in front of the radiator. I only ask that because it seems to work fine at slower speeds where there isn't as much cold air going through cooler. Just a thought?
The single biggest reason the manufacturers run Transmission Fluid through Radiators is because they want the unit to be at a certain temperature range. You wouldn't want to make a hard pass on your engine without warming up the bottom end...
So... again we need to know why the TCC is not being commanded... it xould easliy be tied to temp. What sort of outside ambients are you seeing?
g
This is the same thing that happened to me. I had a TCI 3000 and the lock up clutch went bad. The fluid seemed fine then one day my tranny just ****! The pieces from the lockup clutch got into the tranny pump and things happened very quicky from there on out! Like a cobplete rebuilt tranny and a yank SS3600. Hopefully yours is something else. Be very very careful!
Thread Starter
Joined: Nov 2005
Posts: 2,874
Likes: 314
From: Baltimore County, MD.
Today, I think it was mid 40's, maybe 50, but the more I think about it, since it has been cold out, the lockup has been taking longer than usual to engage, generally speaking. I only drive it to work occasionally, and when I notice that coolant temp gauge is already about up to normal (sorry, I forget the number), but the converter doesn't lockup until a few minutes after that.
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The converter will not lock untill the engine reaches a pre determined temperature ussually around 130 degrees. But as I answered in the other forum , This sounds like engine missfire to me and no it may not set a code, But the PCM sees a missfire then unlocks the converter then when its dosent detect it for a bit relocks. The converter clutch causes the rpm to drop and then the missfire starts again so it unlocks, I ussually suggest and generally its worked that you max the missfire tables and that will likley fix the problem. The PCM can decide to unlock the converter even with the slightest even un noticable miss .
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The converter will not lock untill the engine reaches a pre determined temperature ussually around 130 degrees. But as I answered in the other forum , This sounds like engine missfire to me and no it may not set a code, But the PCM sees a missfire then unlocks the converter then when its dosent detect it for a bit relocks. The converter clutch causes the rpm to drop and then the missfire starts again so it unlocks, I ussually suggest and generally its worked that you max the missfire tables and that will likley fix the problem. The PCM can decide to unlock the converter even with the slightest even un noticable miss .
FormerVendor
Joined: Oct 2006
Posts: 3,123
Likes: 3
From: D-F/W
Without hard data we are all speculating based on experience.
Don't hesitate to get back to me, call me even when you can tell me what the temp was and what the PCM was commanding at the time you feel like it should have been locking up.
From there, I can help you to solve the problem! I walk guys through this very scenario at least once or twice a week, and would be happy to do the very same for you as well.
g
Don't hesitate to get back to me, call me even when you can tell me what the temp was and what the PCM was commanding at the time you feel like it should have been locking up.
From there, I can help you to solve the problem! I walk guys through this very scenario at least once or twice a week, and would be happy to do the very same for you as well.
g
Thread Starter
Joined: Nov 2005
Posts: 2,874
Likes: 314
From: Baltimore County, MD.
As I expected, with my tuner sitting in the passenger seat, and his laptop plugged into my diagnostic connector, the lock-up worked fine today....exactly as it should, and exactly as I figured, LOL. He still still made a few changes in the misfire tables and it has been working great so far....
