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View Full Version : 4l80e swap stuck in 2nd



4wheelin
November 30th, 2007, 11:28 PM
I've fitted a 4l80e to my Patrol with a LS1 turbo and have only got 2nd and reverse. I made the wiring changes as outlined in one of the threads on the forum and have a custom OS that incooperates a 2002 Silverado 6.0l which is 4l80e equiped, I did a trans segment swap. It shows the correct gear in the scan tool from the PNDR sender but the gear the trans is in is 2nd.
P0758, P1860, P0753 codes log which are shift solenoid A and B and torque converter pulse width solenoid. The trans has had a shift improver kit but is still a full auto. I removed the codes to see what the result would be and it still dosent shift out of 2nd but the trans does then reflect that it is shifting gears on the scan tool.
Does anyone know if this could be a result of incorrect wiring on my behalf on the swap or a valve body issue from the shift kit.

Any help appreciated

Joel

joecar
December 1st, 2007, 07:59 AM
Joel,

4L80E limp mode (both shift solenoids off) is 2nd gear and reverse...
this, and those DTC's leads me to think the wiring may be incorrect.

The PCM commands (say) 1st gear, and when it measures the wrong output:input rpm ratio it throws a DTC.

With the scantool bi-directional mode, key on engine off, command each solenoid on/off, you should hear an audible click as each solenoid changes state, you may have to put your ear under the vehicle next to the pan.

Are you sure you had the correct wiring diagrams for all donor vechicles involved...?

Cheers,
Joe

4wheelin
December 1st, 2007, 10:44 AM
Thanks, I'll try that today.

No I'm not sure about the wiring, I thought all 4l60e to 4l80e changes were the same. I got this off the forum.


"It is also necessary to perform a minor harness re-route at the transmission connector. The Brown wire in terminal position "U" needs to go where the White wire is at terminal position "S". The white and tan/black wires are not used in the 4L80-E transmission. Only use the rear mounted VSS sensor."

I am only using the rear vss and have turned the front vss code off.

Thanks

Joel

Lextech
December 1st, 2007, 12:42 PM
You have to use the front VSS sensor! It is a 2 wire sensor. It gets wired to connector C2 pins 22 and 23.

4wheelin
December 1st, 2007, 08:42 PM
I found the problem, no power to the solenoids from the installation,(power on pink/blue wire right up near the TPS, oops.
Why must I use the front vss, I thought it was just for adaptive shift, trans shift speed?? There are a number of threads they say to the contrary. I have the wiring and the plug but opted to not based on what I've read.

Thanks

Joel

Lextech
December 2nd, 2007, 01:35 AM
WOW, I have never heard of not using the front speed sensor. I have built hundreds of Electronic controlled transmissions----They were Japanese. And if I left a VSS connector off of a trans it would go to failsafe mode and be stuck in gear. I'm glad you got it working :cheers:

Wasted Income
December 3rd, 2007, 03:24 AM
Good info guys! I just put the Speed Engineering 4L80E conversion into my buddy's 2002 1500 Silverado. Still waiting for a VIN license to come in my inbox, and then get 'er tuned. Was kinda nervous about why it was as sluggish as it was while pulling it out of the garage. The fact that it still has the 4L60E flash in it, must mean that it was in limp, thus in 2nd gear.

joecar
December 3rd, 2007, 04:43 AM
Yes, the 4L80E commands the solenoids differently than the 4L60E.

If you do get the license later today, pm Tordne (Andrew).

Wasted Income
December 3rd, 2007, 06:45 AM
If you do get the license later today, pm Tordne (Andrew).

Why?

joecar
December 3rd, 2007, 09:26 AM
If you do get the license later today, pm Tordne (Andrew).
Why?Oops... slip of the mind...:doh: I meant to say: "If you do not..."

Wasted Income
December 3rd, 2007, 12:15 PM
Oops... slip of the mind...:doh: I meant to say: "If you do not..."

http://forum.efilive.com/showthread.php?p=59515#post59515

:frown:

joecar
December 3rd, 2007, 01:05 PM
I pm'd Tech Support [if you haven't already].

old mechanic
January 11th, 2008, 09:42 AM
Help!! My check engine light comes on and the truck goes into limp mode. When I checked for error codes I go nothing at the mechanic with his scanner. I used the jumper to get the code manually and got nothing. I replaced the IAC sensor but it didn't fix it. the check engine light still comes on and by the way, the truck runs rich (6MPG). One more comment/observation: When I jumper the diagnostic block to read the error code, I hear some clicking noise behind the light once I turn the ignition to the "on" position. Once the "clicking" noise stops, the light blinks out code "12" which is a precursor to the error code. No error code are sent. at this point, the jumper is removed and the truck start fine and the check engine light stay off for a day or so and then it comes back on and the story repeats.

I would appreciate any suggestions/solutions.

Regards!

GMPX
January 11th, 2008, 11:47 AM
Sorry, but I think a 1992 GMC 2500 is a little bit to early for most of the users on here to have any magic solution.

Cheers,
Ross

hquick
January 22nd, 2008, 11:16 AM
Help!! My check engine light comes on and the truck goes into limp mode. When I checked for error codes I go nothing at the mechanic with his scanner. I used the jumper to get the code manually and got nothing. I replaced the IAC sensor but it didn't fix it. the check engine light still comes on and by the way, the truck runs rich (6MPG). One more comment/observation: When I jumper the diagnostic block to read the error code, I hear some clicking noise behind the light once I turn the ignition to the "on" position. Once the "clicking" noise stops, the light blinks out code "12" which is a precursor to the error code. No error code are sent. at this point, the jumper is removed and the truck start fine and the check engine light stay off for a day or so and then it comes back on and the story repeats.

I would appreciate any suggestions/solutions.

Regards!

Try posting this on one of the truck forums such as:
http://www.pacificp.com/forum/index.php?sid=034f5824b91aa8a4ff212d921199c46e

http://www.performancetrucks.net/forums/forumdisplay.php?f=106

http://www.fullsizechevy.com/forums/

http://www.gmfullsize.com/forum/