Valvebody and pressures - automatic transmission/transaxle

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All of the following statements are true excepte

A. Throttle valves are located inside the transmission valvebody B. As the throttle opening increases, throttle valve pressure decreases C. Increased throttle pressure delays the upshift D. Decreased throttle pressure allows up shifts Answer: As the throttle opening increases, throttle valve pressure decreases

Delayed shift is caused by

An improperly adjusted from start TRUE

Modulated pressure is

Applying pressure

Tech a says that line pressure is an automatic transmission varies with engine rpm. Tech b says that modulator pressure changes with engine vacuum. Who is correct?

Both Techs are correct

Tech a says that sometimes MAF sensors can be cleaned when they have a buildup of dirt and contamination. Tech B says that some manufacturers specifically say not to clean their MAF sensors. Who is correct

Both techs A and B are correct

Hydraulic controlled servos are

Brake bands

The transmission fluid temp sensor can read everything except

Burnt transmission fluid

Epc stands for

Electronic pressure control

If the atf is pink and milky is can be from the vehicle over heating. True or false

FALSE - engine did not over heat

Seal is leaking and the bushing

False

Today's electronic transmission

False

Trans loses pressure with a stuck servo

False

A potentiometer is used for what purpose

It is used for load calculations for automatic transimssions

If an automatic transmission only had a governor and no throttle valve or vacuum modulator what is the shift most likely to be like?

It would shift at the same point no matter what engine load it is

The vacuum modulator converts the engine vacuum signal into

Line pressure

Harsh shifting

Line pressure is too high while cruising

Which of the of the following is a pressure transducer

Line pressure sensor

Slips while turning corners

Low fluid level

The device that varies incoming line pressure using centrifugal force is known as

Modulator pressure

Pressures

Normal 60-120 Wot 90-150 Reverses los 150-300

Tcc is not used for

Not used for shift control

Lacks power from stop

One way clutch is bad or the transmission is slipping

Which of the following sends either simple on or off signals or pulse width modulated signals to the actuator depending on the actuator being controlled

Output driver

Some torque converter clutch (TCC) solenoids are a

Pulse width modulated solenoid

Which gear needs higher line, pressure and the modulator/throttle valve pressure are not used?

Reverse

Internal gear with teeth

Ring gear

The check balls are seperated by a

Separator plate

Map has no effect on what

Shift quality

An electro-mechanical device is used to control oil flow to bands and clutches in an automatic transmission is thes

Shift solenoid

Which of the following has multiple lands designed to block or allow line pressure to pass to a band or clutch in order to apply the gear?

Shift valve

Shift valves are called

Spool valves

Lean mixture

Steal Hesitation Stumble Hard start Misfire

Tcc not working

TFT sensor ect sensor TRUE

Epc regulates line pressure according to engine speed and torque. True or false

TRUE

Epc solenoid is a variable force solenoid

TRUE

Internal transmission cooler is cooled by the engine. True or false?

TRUE

TFT (trans fluid temp sensor) is also a thermistor. True or false

TRUE

Tech A says that a vacuum modulator converts manifold vacuum into an engine load signal. Tech B says modulator pressure changes with the manual valve is moved by governor pressure to force a shift

Tech A

Tech a says that delayed shifts could be caused by a malfunctioning throttle position sensor. Tech b says that TPS data can be used to determine clutch slippage. Who is correct?

Tech A

Harsh 3-4 shift

Tech A says the accumulator piston may be stuck

Tech A says the engine coolant temp (ECT) sensor is an electro-magnetic type of sensor. Tech b says the PCM or TCM uses the ect to vary shift timing and pressure based on engine performance

Tech B

Trs (transmission range sensor)

Tested with an ohmeter

When the governor pressure becomes great enough to overcome the spring pressure and the modulator/throttle valve pressure in the 2-3 shift valve pressure in the 2-3 shift valve, line pressure is allowed to flow to:

The 3rd gear clutch or band

Which of the following works just like a transmission oil temp (TOT) sensor

The Engine coolant temp sensor (ECT)

Shift solenoids can be commanded by

The pcm

Downshift occurs when

The throttle is commanded on

General Motors Powertrain and transmission control modules can calculate a parameter called tap. What can the tap be used for?

To determine how worn the clutch or band is and to adjust shift timing and pressures to match worn clutches and bands

Testing points are located on the

Transmission case

A scan tool and ohmmeter can diagnose a TFT

True

Depth of torque converter should be measure before removal

True

Pressure test an automatic transmission if an internal

True

The tcm info from other ect is tcc control

True

Trans loses pressure as it shifts from 1st to 2nd

True

Bad u joint

True - extension housng

Which of the following is another name for the input shaft speed sensor

Turbine speed sensor

Shift valves are also

VALVES AND SWITCHES

Harsh shifting transmission could be caused by

When the line pressure is too high during normal cruising speeds


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