c5 throwing P1870 code
02-11-2015, 04:47 PM
#1
Heel & Toe
Thread Starter
c5 throwing P1870 code
I'm still having trouble with my A4 tranny in my 2000 c5. Got my tuner and ran diagnostics and found P1870 code, looked it up and read forums saying slippage and TCC valve body issue. They said I need to get a kit for the valve body and some said it's in the programming. Idk but I'm getting frustrated with this and need help. It didn't throw the code all day yesterday but right before I pulled in my driveway today it threw that code. Do I need to get a valve body kit or what?
02-12-2015, 02:25 PM
#3
I wasn't getting the code but I knew my transmission was running hot and the torque converter was slipping some last summer so I installed the kit in my 2000 A4. It didn't seem to help my issue so I need to keep looking - my next effort will be to do the tranny cooler in the radiator flow test. The clutch in my torque converter may also be no longer holding well. When I got the modified car last year there were some things in the tune I didn't care for, one being that it locked the converter in 3rd and 4th and allowed it to shift between the gears holding the converter locked. I've got it now only locking in 4th.
The kit solves a well-known issue in the pulse-width-modulated (PWM) torque converter lockup hydraulic circuits, introduced in the 4L60 in 1995. When locked a valve is constantly moving back and forth. Over time this movement tends to wear the valve's bore causing leakage around the valve affecting its operation and the downstream operation of the torque converter clutch. The kit replaces this valve with one that either locks or unlocks the converter, unlike the PWM control which allows some variable application force of the clutch based upon the electronic pulse width controlling the stock valve.
I installed this kit myself with the car on jackstands. I've rebuilt more than one 4L60 so working on the valvebody didn't intimidate me. I'm pretty sure I didn't need to remove the valvebody to install the kit - I don't recall having to replace the gasket between it and the separator plate between it and the tranny.
For me the most intimidating part was the tranny refill procedure requiring topping off the tranny fluid with the engine- while under the vehicle - haven't had to do that on my trucks.
The kit solves a well-known issue in the pulse-width-modulated (PWM) torque converter lockup hydraulic circuits, introduced in the 4L60 in 1995. When locked a valve is constantly moving back and forth. Over time this movement tends to wear the valve's bore causing leakage around the valve affecting its operation and the downstream operation of the torque converter clutch. The kit replaces this valve with one that either locks or unlocks the converter, unlike the PWM control which allows some variable application force of the clutch based upon the electronic pulse width controlling the stock valve.
I installed this kit myself with the car on jackstands. I've rebuilt more than one 4L60 so working on the valvebody didn't intimidate me. I'm pretty sure I didn't need to remove the valvebody to install the kit - I don't recall having to replace the gasket between it and the separator plate between it and the tranny.
For me the most intimidating part was the tranny refill procedure requiring topping off the tranny fluid with the engine- while under the vehicle - haven't had to do that on my trucks.
Last edited by enoniam; 02-12-2015 at 02:28 PM.
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Grey666 (08-15-2020)
02-12-2015, 02:38 PM
#5
Whoever rebuilt it should have inspected that valve bore for wear. Method is to place a small flashlight pointing down into the interior end of the valve bore and with the valve in place observe how much light is coming around the perimeter of the valve. A very small crescent is acceptable but I don't believe there's a true measurement that can be easily obtained by the rebuilder to get an objective determination of how close it is to needing one of the various kits on the market applied to the valve body. Maybe your rebuilder will give you a cost break on installing the kit since its been under a year since it was in his hands.
02-12-2015, 02:49 PM
#7
Heel & Toe
Thread Starter
Well that's the thing when I got it someone had already put a program in it so I never had the stock tune to begin with but I guess I can go to the dealer and get them to put the stock tune back in then program it the way I want it
02-12-2015, 03:58 PM
#10
As 3boystoys suggested getting a stock tune in it may help. You can also adjust the PWM duty cycle table but I think you're going to need a more powerful tuning tool such as HPTuners to do that. I did with my tune before installing the kit but it didn't help my situation either.
02-12-2015, 10:06 PM
#11
He is right. The 1870 code is a very common problem with the 4l60e. The pwm valve wears out the bore in the valve body. When I worked at the dealer years ago we were putting valve bodies in these for a fix. There was a bulletin out for this. Also make sure you replace the separator plate because the check ***** hammer on the plate and wallow out the holes.
02-13-2015, 10:02 AM
#12
He is right. The 1870 code is a very common problem with the 4l60e. The pwm valve wears out the bore in the valve body. When I worked at the dealer years ago we were putting valve bodies in these for a fix. There was a bulletin out for this. Also make sure you replace the separator plate because the check ***** hammer on the plate and wallow out the holes.
02-13-2015, 10:15 AM
#13
Heel & Toe
Thread Starter
I'll have to take it back to him and let him look at it I remember him saying he bored the valve body a Lil but he bought a trnasgo kit for it... maybe it has already messed up