4L60E shifting problems 2003 LQ4

[solidaxel]

Finally drove the truck around the block.
First gear works great, but it shifts weird
1st to third and when I try to throttle it a bit it wants to down shift!
Back to the garage
Do you think it might be the computer or the transmission, I know that is not much info, but I do not want to drive until I do some more homework.

[Custom 68]

check all your plugs to your transmission, it needs the speed and all the other inputs to function correctly.
The lq4 may have possibly been mated to a 4l80 tranny, that will require different wiring and yes the computer will need to be worked over to correctly shift the 4l60.
Do you know what computer and transmission came with that motor originally?

[ls1nova71]

I agree, its probably a tune issue. An LQ4 would have originally had a 4l80e behind it and if you didn't change the tune it won't work right.

[solidaxel]

I purchased the whole package together, but the computer was exchanged and re programed for this combo, and was to be tested as a whole unit, ECU TAC and DBW foot feed

[Custom 68]

Well that said I would call them back and find out. I do know the wiring is similar but different for the 2 transmissions. My harness had provisions for both and I mis read some of the info and hooked it up wrong and it would not work. It was my issue and I quickly found the problem.
Check your wiring first then call them.

[solidaxel]

I called them a few min ago and he said and they said 'Send it back", he said has programed many many of these with the same results "0" he said it was most likely a hard ware problem!.
I will keep you posted!
One more vote for finding a GOOD local programmer, turn around time!!

[mooseknuckles]

how many sensors in the harness for the tranny?

[solidaxel]

Originally Posted by mooseknuckles

how many sensors in the harness for the tranny?

Do you mean pins or contacts?
I have the old harness I will compare the quantity or pins

[solidaxel]

Originally Posted by mooseknuckles

how many sensors in the harness for the tranny?

How is your outside C- meter this time of year!!!
Take a look at our TV KOLD Ch.13 weather this week, and the sunset pics.

[BR3W CITY]

So if you have an extra plug hanging down in your harness, then your harness was wired for the second vss (ISS) for the 4l80e...if not then it should be the 60e single plug you need. Also, disconnect that plug and clean it off with contact cleaner, as sometimes trans fluid drips from the seal or seeps from the top or the pan or bolts and can infiltrate the connector. Sometimes even wiggling it will give you a sign.

Does the accell pedal work right when your in neutral, i.e does the throttle respond normally? (i assume so, as usually dbw either works or it doesn't).

If your vss is not plugged in all the way, or pinched/miswired, then the strange sensations your feeling are possible. Its also plenty possible that he didn't do a segment swap and the ecm wants the second input from the ISS, it may "think" you have an 80e.
Also, check the wiring on the brake switch, and that its adjusted properly. Lockup functions are directly affected by it and the tune, and can make trans functions very jerky and wonky.

Codes?

[solidaxel]

[QUOTE=BR3W CITY;6531472]So if you have an extra plug hanging down in your harness, then your harness was wired for the second vss (ISS) for the 4l80e...if not then it should be the 60e single plug you need. Also, disconnect that plug and clean it off with contact cleaner, as sometimes trans fluid drips from the seal or seeps from the top or the pan or bolts and can infiltrate the connector. Sometimes even wiggling it will give you a sign.

Does the accell pedal work right when your in neutral, i.e does the throttle respond normally? (i assume so, as usually dbw either works or it doesn't).

If your vss is not plugged in all the way, or pinched/miswired, then the strange sensations your feeling are possible. Its also plenty possible that he didn't do a segment swap and the ecm wants the second input from the ISS, it may "think" you have an 80e.
Also, check the wiring on the brake switch, and that its adjusted properly. Lockup functions are directly affected by it and the tune, and can make trans functions very jerky and wonky.

Codes?[/QUOTE

I like that Jerky & wonky, that is what it does on the second shift, and not second gear !!

The extra plug that I have is attached to the stock harness on the shelf.
I will pay some attention to the male part of the transmission plug as the female is clean and new.

The gas pedal is super responsive and works great.

I did replace the brake switch so that it has 12VDC with the brake off to the TCC., on the cruise end of the plug, the brake lights will go on with 1 inch pedal movement so the TCC contact is opened at 1 inch

The first thing I am going to do is count the pins!

[BR3W CITY]

You didn't happen to mention codes, is anything showing up? Sometimes trans codes won't pop cel the same, but I'm curious if anything is signaling.

Skipping second gear can also be a mechanical failure, like the solenoid isn't working (or getting voltage), the valve body has something gunked in it, or a physical problem with second.

We gotta eliminate 1 thing at a time haha. It would be nice if we could plug it into hpt and see if it commands second.


LOL I think we need to should put HP Tuners on the list of required parts for a swap.

[solidaxel]

No codes,

I did have the truck to the transmission shop and he connected "his" transmission controller to the trans. with my cannon plug removed and he said the transmission was working just fine, He thought the problem was with the computer,

I did look at the original cannon plug and counted the wires and there are 13 in each one BUT the yellow and green are transposed at the plug.
I did not follow them to the computer connector pin outs, so they MAY be transposed there which would not be a error.
The grey plug is the stock and the lighter one is new plug

[BR3W CITY]

Well, thats the 60e plug (the 80e looks the same but has or uses less pins). On the stock plug, the green wire should be Solenoid A, and the Yellow/black wire is Solenoid B.

Like you said, it doesn't mean that they didn't just color it wrong but wire it right, though it gives you a clear point to look at. You can wire swap those two and see if there is a change...but without being able to see into the computer, we'll still end up with a question mark on that part.

[ls1nova71]

I would definitely take a volt meter and check those two wires at the PCM to make sure...

[solidaxel]

Originally Posted by ls1nova71

I would definitely take a volt meter and check those two wires at the PCM to make sure...

O K, which connector and what pin position should they correspond with?

[Wasted Income]

[ls1nova71]

Originally Posted by solidaxel

O K, which connector and what pin position should they correspond with?

Yellow/black would be the 2-3 shift solenoid and should be on C2 pin 47, the lt green would be the 1-2 shift solenoid and should be on C2 pin 48. I could see the transmission doing some weird stuff if the PCM activated the 2-3 shift before the 1-2.

[solidaxel]

O K, thanks I am going to prove 47 & 48 on the green connector right ?

[solidaxel]

Update,
O K I did unplug the green computer plug and pined the two positions at the cannon plug at the transmission.
I compaired them to the stock wire harness I have and they are TRANSPOSED, green and Yellow with a black tracer is backwards with the green wire per he stock harness.

NOW which end do I make the change, which is the easiest to change with OUT cutting and splicing????

The transposition is in the cannon plug, but how do I dis assemble it?

[solidaxel]

Originally Posted by ls1nova71

Yellow/black would be the 2-3 shift solenoid and should be on C2 pin 47, the lt green would be the 1-2 shift solenoid and should be on C2 pin 48. I could see the transmission doing some weird stuff if the PCM activated the 2-3 shift before the 1-2.

Like BR3W said JERKY & WONEY if these were transposed that is what t would shift like !!
I may not be counting the positions on the green connector properly BUT they are reversed or transposed with each other (stock & aftermarket)

[truckdude239]

I'd just swap the pins at the computer side

[solidaxel]

Originally Posted by truckdude239

I'd just swap the pins at the computer side

.............. O K, I need a little O J T, will all of the other pins fall out when I figure out how to get it apart!!!

[solidaxel]

here is where I think the problem will be corrected
This is where I found the problems.

[Wasted Income]

Crap...my image of the pinout somehow turned into a huge megasquirt image. Well that's what I get for stealing stuff from their site...