Chevrolet venture problem P1811 maximum adapt and long shift

P1811 - Maximum Adapt and Long Shift Mode Chevy, Pontiac, Saturn, and Buick Front Wheel Drive Vehicles The P1811 code is one of the most common codes for transmissions in 1997-on GM front wheel drive vehicles. Symptoms of this code include a check engine light illuminated and harsh shifting. Cycling the key on and off may cure the harsh shifting until the criteria for the code is met once more. We are going to cover what causes the code to set and repair options.

Code Criteria
If a shift into any gear other than reverse and forward engagements takes longer than 0.65 seconds to complete, code P1811 will set. The Powertrain Control Module will then command maximum line pressure inside of the transmission, resulting in harsh shifting. The PCM will also command the check engine light or service engine soon light to be illuminated when P1811 is set. Basically, the PCM is sensing a slip, and is increasing line pressure to maximum in order to prevent the transmission from hurting itself further.
Repair Options
In 2002, GM release a technical bulletin for the P1811 code. See the bulletin by clicking this link http://bit.ly/P1811_Bulletin. The bulletin states that a mechanical problem in the Pressure Control (PC) solenoid, contamination in the valve body, or incorrect fluid level can cause the P1811 to set. Those problems could definitely cause a P1811, but what they failed to mention in the bulletin is, what exactly is the PCM looking for when setting P1811. It's looking for a slip of 0.65 seconds or longer to set the code. See http://bit.ly/P1811_Diag_Tree. So it's not as cut and dry as the bulletin makes it to be. A burnt clutch pack, stripped overdrive clutch hub, worn accumulators, worn valving especially the actuator feed limit valve, and just high mileage can all cause this code to rear its ugly head. All of which would require transmission disassembly to repair. Now I'm not saying that P1811 is going to require a major transmission overhaul every time a vehicle comes into the shop with the code. I'm saying that it is not always going to be as simple as just changing out a solenoid.
How to Know if a Solenoid will Repair the Problem
It is impossible to know for sure what the internal shape of a transmission is while the transmission is still in the car. The first thing to check is the transmission fluid. If the fluid level is low, add automatic transmission fluid (ATF) until full. Remember that transmission fluid needs to be checked while the engine is warm and running with the shifter in the Park position. After the fluid level is OK, drive the vehicle to your nearest People's Transmission certified shop to have it checked. If the fluid level was low, there is a leak somewhere that has to be repaired. The shop will then test drive the vehicle while monitoring data on a scanner that is communication with your vehicle's PCM. After that, the shop will most likely recommend a pan drop to see if any contamination is being produced inside of the transmission. If contamination in the form of clutch material or metal is present, then a solenoid replacement will be a waste of money. If the pan is clean, fluid is in decent shape, and the mileage is below 80,000 miles or so, then maybe a solenoid will fix the problem. The thing to remember is, if the shop recommends a solenoid, then they are looking out for your best interests. It still may not fix the problem, but from what they have seen during their checkout, a solenoid replacement is worth the gamble. If the shop recommends a transmission overhaul, ask them what they found that makes them think that is the only option.
Maybe this will help, good luck.OKI1IT

P1811
The transmission pressure is modified by an adaptive modifier which controls the shift execution time. This diagnostic tests the time required to accomplish the shift. If the shift takes longer than 0.65 seconds and the adaptive modifier cannot shorten this time, then a counter increases by one.
If the PCM detects a counter value of 2 during one trip, then DTC P1811 sets. DTC P1811 is a type C DTC
The 1-2, 2-3 or 3-4 shift is longer than 0.65 seconds, twice in one trip.
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Ask the customer about possible overloading, exceeding the trailer towing limit, or towing in overdrive.

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Ensure that the current PCM calibration is correct for the final drive ratio.

1. Use the scan tool snapshot mode in order to record the shift times.
2. Drive the vehicle in D4 in order to obtain a 1-2, 2-3 and 3-4 upshift.
3. Record the shift times.

Did all the shift times exceed the specified value?
0.65 seconds
Perform the Line Pressure Check Procedure.
Refer to the Line Pressure Check .
Is the line pressure within specifications?
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Go to Diagnostic Aids
You may want to take this to the dealer !

P1811....Long shift and maximum adaptation limit reached
It means that PCM have found long shift and the adaptation pressure is at maximum
Seal cut, clutch worn out. and so on overhaul trans.
check oil level first
hope it help

http://ww2.justanswer.com/uploads/mcvgreg/2008-07-13_150302_2000-Century-P1811-Chart.pdf

Have the transmission control module tested.

code po742 torque converter clutch circuit stuck on conditions. code p1811 maximum adaptive and long term shift conditions.see this code transmission fluid is low and contaminated.change transmission fluid and filter see if this help your problem.you need to fix this problem fast transmission is not getting enough fluid to work.

P1811 Maximum Adapt And Long Shift

CODE PO218 - TRANSMISSION FLUID OVER TEMPERATURE.TRANSMISSION FLUID IS LOW OR CONTAMINATED BURNT OR DIRTY.CHECK TRANSMISSION COOLER LINES FOR DAMAGE OR RESTRICTION. CODE PO742 - TORQUE CONVERTER CLUTCH CIRCUIT STUCK ON. CODE P1811 - MAXIMUM ADAPTIVE LONG TERM SHIFT. CODE U1301 - CLASS 2 CIRCUIT SHORT TO BATTERY.POSSIBLE CAUSE CLASS 2 SERIAL DATA LINE WAS IN A HIGH STATE FOR 3 SECONDS DUE TO A SHORT TO VREF OR SYSTEM POWER. ONE OR MORE MODULES ON CLASS 2 LINE HAS AN SHORT TO POWER.LOOKING AT ONE OF THE CODES.TRANSMISSION GETTING TOO HOT.DUE TO OVERHEATING ENGINE OR YOU ARE TOWING OR PULLING MORE WEIGHT THAN YOUR VECHICLE CAN HANDLE.CAUSING ENGINE AND TRANSMISSION TO OVERHEAT.

The problem is probably a bad Electronic Pressure Solenoid (EPC). Have the computer scanned at a dealership or a transmission shop to verify this. The code will probably be a P1811. The P1811 code sets because the transmission takes longer than 0.65 seconds to shift, then the computer commands maximum line pressure to make the car shift as fast as possible to avoid burning the clutches. Replacing the EPC is an expensive job, however, you can install a shift kit to speed up the shifting, and probably fix the problem. The shift kit is available from a company called TransGo. If you go to www.transgo.com you can look up a distributor in your area. The kit you will need is the SK®4T65E. Installing the shift kit is pretty easy for the 'shade tree mechanic'; if you can change your own transmission fluid, you can most likely install this kit yourself.

P0742: Torque Converter Clutch Circuit Stuck On (transmission area)

P1811: Maximum Adapt and Long Shift 2.4L and 3.1L (transmission area)

You need to talk to a transmission specialist.