Limp mode??
Limp mode?? Just got my turbo car running yesterday. Trans is a built 4l60 with around 3-4k miles and previous setup was around the 420rwhp range.
Drove it to gas station, local auto parts store and back home. Logged everything and all looked fine. Took it to
A buddies house about 5 miles away and back home, all was fine. Let everything cool, checked all fluids, went to another buddies house. When I picked him up, car would not pull out hardly. It was like e-brake was on. When I gave the car much more gas than it should have taken to pull out, it's like it "broke loose". Ran fine rest of way home other than the only gear it had was 3. Trans temps stayed around 200 and rose to 215 about the time I got it home.
Another thing to note, car never entered boost. Max rpm was around 3600, TPS never went over 35%. It's not like I was won't hard on it.
Kept it outside a while to cool, started it up and it pulled right in the basement without issue. Not looked for any DTCs yet as I'm pretty disgusted with it since it was the first time driving since September. Trans fluid looks perfect. Converter is a custom unit from TCI. Someone give me their thought and hopefully good news
Drove it to gas station, local auto parts store and back home. Logged everything and all looked fine. Took it to
A buddies house about 5 miles away and back home, all was fine. Let everything cool, checked all fluids, went to another buddies house. When I picked him up, car would not pull out hardly. It was like e-brake was on. When I gave the car much more gas than it should have taken to pull out, it's like it "broke loose". Ran fine rest of way home other than the only gear it had was 3. Trans temps stayed around 200 and rose to 215 about the time I got it home.
Another thing to note, car never entered boost. Max rpm was around 3600, TPS never went over 35%. It's not like I was won't hard on it.
Kept it outside a while to cool, started it up and it pulled right in the basement without issue. Not looked for any DTCs yet as I'm pretty disgusted with it since it was the first time driving since September. Trans fluid looks perfect. Converter is a custom unit from TCI. Someone give me their thought and hopefully good news
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Joined: Aug 2010
Posts: 7,323
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From: Ann Arbor, MI
A code, likely an engine code, caused the trans to enter limp mode, which is 3rd gear in a 4L60E. That also disables the TCC lockup. Did you scan for codes? Don't you have HPT?
I have a hunch that the PCM limits RPMs when the trans exceeds a certain temp. I have no proof of that and no one has ever confirmed or denied it, so take it or ignore it, but it seems to match your symptoms.
I suspect that you will find some codes and when you fix that, it will all work perfectly again. It doesn't sound like anything wrong with your trans.
I have a hunch that the PCM limits RPMs when the trans exceeds a certain temp. I have no proof of that and no one has ever confirmed or denied it, so take it or ignore it, but it seems to match your symptoms.
I suspect that you will find some codes and when you fix that, it will all work perfectly again. It doesn't sound like anything wrong with your trans.
A code, likely an engine code, caused the trans to enter limp mode, which is 3rd gear in a 4L60E. That also disables the TCC lockup. Did you scan for codes? Don't you have HPT?
I have a hunch that the PCM limits RPMs when the trans exceeds a certain temp. I have no proof of that and no one has ever confirmed or denied it, so take it or ignore it, but it seems to match your symptoms.
I suspect that you will find some codes and when you fix that, it will all work perfectly again. It doesn't sound like anything wrong with your trans.
I have a hunch that the PCM limits RPMs when the trans exceeds a certain temp. I have no proof of that and no one has ever confirmed or denied it, so take it or ignore it, but it seems to match your symptoms.
I suspect that you will find some codes and when you fix that, it will all work perfectly again. It doesn't sound like anything wrong with your trans.
Only, no lockup, etc. I looked at codes and couldn't see any Trans related other than Shift solenoid. Yes, I do have HPT. I can list the codes it showing If you would like. I was hoping you would chime in Edit.
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Joined: Aug 2010
Posts: 7,323
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From: Ann Arbor, MI
Sure, list the codes, either here or in the Tuning section where I know you are also active.
I don't know all the engine codes that will put the trans into limp, but perhaps one of the tuning experts does.
I don't know all the engine codes that will put the trans into limp, but perhaps one of the tuning experts does.
Ok, I'll post them up shortly. May post them here and in the tuning section as well.
Just went downstairs and went over the car. Backed it out, 2,3, and OD worked fine. When I manually pulled the car into 1, it was the same thing. Acted like the ebrake was on. Odd that it did it yesterday in 3 and now its in 1?? Only code transmission related I seen in the DTCs was a P-0758 (shift solenoid B electrical).
I just posted a similar thread in the Diag. and Tuning section to see if I could get any answers over there. Really hoping this is just a small fix. Thanks in advance for the help guys..
I just posted a similar thread in the Diag. and Tuning section to see if I could get any answers over there. Really hoping this is just a small fix. Thanks in advance for the help guys..
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Joined: Aug 2010
Posts: 7,323
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From: Ann Arbor, MI
Google "4l60e P0758". It brings up many threads here including this one:
https://ls1tech.com/forums/automatic...ode-p0758.html
Some people get solenoid codes due to their high stall converter, but I think it is P0756:
https://ls1tech.com/forums/automatic...500-4l60e.html
https://ls1tech.com/forums/automatic...ode-p0758.html
Some people get solenoid codes due to their high stall converter, but I think it is P0756:
https://ls1tech.com/forums/automatic...500-4l60e.html
Last edited by mrvedit; May 25, 2015 at 07:36 PM.
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Thanks a a ton man. I'm one of the many who never think to Google stuff. At was a great read, sounds like my problem exactly. I hate it but I'm extremely happy that it sounds like it's not a mechanical issue.
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I ordered the 2-3 solenoid today but had a quick question. Do you think it's possibly the sprag? I don't see why it would be but won't know for sure if it's fixed until tomorrow. It's killing me not knowing.
I ordered the 2-3 solenoid today but had a quick question. Do you think it's possibly the sprag? I don't see why it would be but won't know for sure if it's fixed until tomorrow. It's killing me not knowing.
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Joined: Aug 2010
Posts: 7,323
Likes: 529
From: Ann Arbor, MI
It does not sound like the forward sprag.
However your "It was like e-brake was on" concerns me that there is a problem in the low/reverse clutch, which also has a sprag.
Sorry, I just don't have the experience to diagnose low/reverse problems, partly because they are relatively rare.
Reminds me of the opening scene of Dirty Harry. Go to 2:30:
However your "It was like e-brake was on" concerns me that there is a problem in the low/reverse clutch, which also has a sprag.
Sorry, I just don't have the experience to diagnose low/reverse problems, partly because they are relatively rare.
It's killing me not knowing.
Last edited by mrvedit; May 26, 2015 at 06:07 PM.
That movie is a classic. Almost made me forgot about my problems for a minute. . 
I've looked for codes in particular that would throw the car into limp and can't find any specifics. Ready some of the symptoms of it leave me in the middle as to whether that would have happened or not. I'm going to clear the MAF error and the eVap one as well. Read something today about those being problematic.
I've looked for codes in particular that would throw the car into limp and can't find any specifics. Ready some of the symptoms of it leave me in the middle as to whether that would have happened or not. I'm going to clear the MAF error and the eVap one as well. Read something today about those being problematic.
Joined: Nov 2003
Posts: 6,216
Likes: 236
From: Wichita KS / Rancho San Diego
I'll give you my $.02 on my limp mode issues.
When I first got my car it would go into limp mode for seemingly no reason mainly on hot summer evenings after driving for a while. I thought at first that my tranny was going away on me! I took it to the dealership and they installed an updated factory tune and it never happened again - that is, not until I installed a SS3600 converter. I think this was the temp problem mentioned above.
With the SS3600, I got a code for the VSS sensor. Replaced it and it didn't help. Finally I tuned out the P0758 and that solved it. If clearing the MAF error and the solenoid don't solve it, then tuning out that DTC may do it for you.
What kind of car and what OS are you running?
When I first got my car it would go into limp mode for seemingly no reason mainly on hot summer evenings after driving for a while. I thought at first that my tranny was going away on me! I took it to the dealership and they installed an updated factory tune and it never happened again - that is, not until I installed a SS3600 converter. I think this was the temp problem mentioned above.
With the SS3600, I got a code for the VSS sensor. Replaced it and it didn't help. Finally I tuned out the P0758 and that solved it. If clearing the MAF error and the solenoid don't solve it, then tuning out that DTC may do it for you.
What kind of car and what OS are you running?
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Joined: Aug 2010
Posts: 7,323
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From: Ann Arbor, MI
RevGTO - Are you sure it was code P0758 you disabled and not P0756?
I don't have either code disabled and have never had either code even with three different 3600 converters.
There are plenty of threads here and on other forums about the difficulties of resolving these codes.
I don't have either code disabled and have never had either code even with three different 3600 converters.
There are plenty of threads here and on other forums about the difficulties of resolving these codes.
I'll give you my $.02 on my limp mode issues.
When I first got my car it would go into limp mode for seemingly no reason mainly on hot summer evenings after driving for a while. I thought at first that my tranny was going away on me! I took it to the dealership and they installed an updated factory tune and it never happened again - that is, not until I installed a SS3600 converter. I think this was the temp problem mentioned above.
With the SS3600, I got a code for the VSS sensor. Replaced it and it didn't help. Finally I tuned out the P0758 and that solved it. If clearing the MAF error and the solenoid don't solve it, then tuning out that DTC may do it for you.
What kind of car and what OS are you running?
When I first got my car it would go into limp mode for seemingly no reason mainly on hot summer evenings after driving for a while. I thought at first that my tranny was going away on me! I took it to the dealership and they installed an updated factory tune and it never happened again - that is, not until I installed a SS3600 converter. I think this was the temp problem mentioned above.
With the SS3600, I got a code for the VSS sensor. Replaced it and it didn't help. Finally I tuned out the P0758 and that solved it. If clearing the MAF error and the solenoid don't solve it, then tuning out that DTC may do it for you.
What kind of car and what OS are you running?
Edit, their is a thread a couple posts below mine were a guy was doing same thing on
His 80e and said he cleared the 0758 code and it fixed his. I will say this, being the way this car has fought me so far, this will
Not fix it. We will see tonight hopefully.
Joined: Nov 2003
Posts: 6,216
Likes: 236
From: Wichita KS / Rancho San Diego
RevGTO - Are you sure it was code P0758 you disabled and not P0756? I don't have either code disabled and have never had either code even with three different 3600 converters.
There are plenty of threads here and on other forums about the difficulties of resolving these codes.
There are plenty of threads here and on other forums about the difficulties of resolving these codes.
Ok, the 0758 code is for
Shift solenoid B. Looking at a transmission diagram, solenoid B is the 2-3. Before I dropped the pan and did all of that, I used VCM controls in HPT and commanded the 1-2 and 2-3. Well, you could hear the 2-3, not the 1-2 though?? Cleared te codes that was thrown and set the ones that I knew I wasn't needing to report no error.
So, what do you guys do now? Change 1-2 or 2-3?
Shift solenoid B. Looking at a transmission diagram, solenoid B is the 2-3. Before I dropped the pan and did all of that, I used VCM controls in HPT and commanded the 1-2 and 2-3. Well, you could hear the 2-3, not the 1-2 though?? Cleared te codes that was thrown and set the ones that I knew I wasn't needing to report no error.
So, what do you guys do now? Change 1-2 or 2-3?
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Joined: Aug 2010
Posts: 7,323
Likes: 529
From: Ann Arbor, MI
If one solenoid is suspected, I suggest replacing both as they are only $12 each.
Two reasons for that:
1. If one is bad the other is likely on its way out.
2. People get disoriented upside under the car and replace the wrong one.
Two reasons for that:
1. If one is bad the other is likely on its way out.
2. People get disoriented upside under the car and replace the wrong one.
One last question:
Crawled under car to swap the solenoids tonight. Found a 4 pin female connector on the the passenger side tail on the transmission that the guy who repinned the computer didn't plug up. Can't find a connector for it though..
lol, Where the hell does it go?
Crawled under car to swap the solenoids tonight. Found a 4 pin female connector on the the passenger side tail on the transmission that the guy who repinned the computer didn't plug up. Can't find a connector for it though..
lol, Where the hell does it go?
