Question about 1994 Oldsmobile Silhouette

1 Answer

Transmission downshift problem

1994 Olds van. After about 40-50 miles at fwy speed and going uphill, tranny converter will unlock. It then almost imediately downshifts to 3rd gear. It remains in that state until ignition switch is turned OFF and then it operates normally until the next hill???

Posted by on

1 Answer

  • Level 1:

    An expert who has achieved level 1.

    Hot-Shot:

    An expert who has answered 20 questions.

    Corporal:

    An expert that hasĀ over 10 points.

    Mayor:

    An expert whose answer gotĀ voted for 2 times.

  • Contributor
  • 21 Answers

This vehicle had a problem with the valve bodies in the transmission. There are several servos that assist the transmission to shift. This problem is best diagnosed by a local trans shop that can do an OBDII test to see if the trans has the proper voltages to the servos as well as to check the pressure.

Posted on May 21, 2009

1 Suggested Answer

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
goodluck!

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

Car surging


Is the car equipped with the Automatic Transmission?
If so, read on.
Otherwise skip to the end and answer some questions.

POSSIBLE SCENARIO:
I have observed a condition where my car surges slightly when the torque-converter clutch (TCC) cycles between lock and unlock when driving on an uphill grade.
First some basics and history that will explain why the TCC is used.

Engine, Torque Converter, TCC, and Transmission relationship--
The TCC allows for a solid connection between the engine and transmission which allows the input to the transmission to rotate at the same speed as the engine.
Without a TCC, there is slippage between the engine and automatic transmission. The slippage is greatest at low engine RPM. That is what allows the engine to run with the automatic transmission in gear, like when you first shift into gear or stop at a stop sign. When the throttle pedal is depressed, the engine RPM begins to increase and the torque converter begins to slip less and less the more the engine RPM increases. The car moves. But even at cruising speeds the torque converter slips slightly. Engine RPM is greater than transmission input RPM, which is realized as slight decrease in fuel efficiency.
When acceleration is complete and a constant speed is being maintained, the engine power output is reduced to the point where the TCC can engage and eliminate any slippage between the engine and transmission. If the car has a tachometer the engagement of the TCC can be verified when a slight reduction in engine RPM observed without a corresponding change in vehicle speed.
One method used to test the operation of the TCC is as follows:
Find a flat section of road where it is safe to perform the test.
Reach a steady speed and keep the gas pedal depressed with one foot. While observing the tachometer (or listening for an increase in engine RPM), with the other foot depress the brake pedal enough to activate the break light switch but not enough to engage the brakes. When the brake light switch activates, the TCC receives a signal to disengage. With the gas pedal being held steady, release the brake pedal and the engine RPM should decrease when the TCC engages.
Old cars with Automatic Transmissions did not use a TCC. I believe the TCC was put in use in an attempt to increase fuel economy.

MY EXPERIENCE WITH SIMILAR SYMPTOMS
The condition that causes that issue on my car is this:
- A slight uphill grade increases the load on the engine.
The car tends to gradually slow and it is necessary to depress the gas pedal to maintain speed.
- Depressing the throttle pedal (manually, or automatically with cruise control engaged) signals the torque converter clutch to unlock when the load increases slightly. (A more drastic load increase would signal the Transmission to downshift to a lower gear.) The corresponding increase in engine RPM and output is enough to compensate for the reduction in speed. When the vehicle speed, engine RPM, and throttle position stabilize to the point that the TCC will engage and the engine RPM will reduce in correspondence with TCC engagement. Now, if the road conditions have not changed, power output is not enough to maintain vehicle speed. With the increased load caused by full engagement between engine and transmission, and the cycle (surging) repeats itself until the road conditions change.

Does that help?
If not:

QUESTIONS
Please define the symptoms.
What are the road conditions when the surge occurs? (A slight uphill grade?)
What is the frequency of the surge?
Does the engine power output have a noticeable surge?
Is there a speed change related to the surge?
Does the tachometer move up and down with little or no change in vehicle speed?
Are all instrument indication in the normal range?
What else has changed?

Good luck!

May 24, 2014 | Subaru Impreza WRX STi Cars & Trucks

1 Answer

1996 F350 4x4 7.5l Shifts fine when cold. After 30-40 miles tranny sticks in 1st gear while accelarating from stop and will rev to 4500 RPM before slamming into third gear. If you let it rev to approx....


Changing the fluild ( all of it) might fix it if your lucky. Something overheating sounds possible. Any cooling system problem can cause this and cleaning the cooling system and flushing out the transmission cooler in the raditor may go a long way towards fixing your problem. dity raditor and or coolant will cause this problem. I you clean everything real good and then go and drive it and it goes longer but still does it your in for another rebuild. this time put in a new raditor to make sure the transmission lasted as long as it's supposed to. It's possible the throttle pressure was'nt set right and the trans upshifts too early and therefore the transmission gets too hot cause the engine is going too slow to make good transmission pressure and the slipping transmission overheats. again even after corrected it'll still do it as the transmission internal seals are adamaged by heat and it'll need to be rebuilt again.

Jul 27, 2011 | Ford F-350 Cars & Trucks

1 Answer

Do I have to pull the tranny to fix it,or is there a cover I can take off to get to it.How much is the part?


You dont want to start buying 250 dollar parts , that you dont know you need.You need to hook a scan tool to this thing and see if the downshift is even being comanded. When you come to a stop the scan should have 0 output rpms and should say the trans is in low gear.If you have say 14 rpms showing on the output speed sensor at a stop the the computer will think the vehicle is still moving and not allow for a downshift.This trans does not have govenor solenoid and sensor like the earlier jeeps did.Its electronic controls are more like the mini vans with the 604 trans. I have seen mini vans have a downshift bump and / or no downshift because the plugs wires were too close to the wiring harness and creating a falseoutput speed signal. It will pay to have this Transmission diagnosed by someone with knowledge and the tools.

Jan 26, 2011 | 2001 Jeep Grand Cherokee

1 Answer

1994 Ford E350 transmission seems like it slips at 45-55 MPH.


If you went 1k miles since that same issue occurred I would look at the transmission. A faulty torque converter, clogged fuel filter, or a clogged CAT can cause a delay in the shifting but it would happen right away not 1k miles later.

May 05, 2010 | 1994 Ford Econoline

1 Answer

95 geo manual tranny have had problem down shifting to 1st gear for couple months now 2nd is getting hard to downshift and upshift have replaced rubber bushings bolts etc.on shift linkage adjusted etc.


Sounds like your synchronization rings inside the tranny are wearing out try changing the transmission oil and adding product like lucas oil treatment , if it helps lay off the downshifting until your ground speed matches your engine speed for the gear your ring to go in. like really slow speeds ...

Jun 12, 2009 | 1995 Geo Metro

1 Answer

Transmission downshifts hard when I let off the gas at slow speeds


Transmission sensor.your gear ratio was not set up properly..Its supposed to be mapped out soo the tranny shifts at a neutral rpm(around 2500-3400 rpm) its punching into gear correct?could have been a rebuilt tranny in which case they just replace the current problem..Or it could be a flywheel.1st thing to get done is to change the transmission fluid and filter.Goto midas or somewhere like they and they call it a flush and fill and it costs around $160 which is best case scenario.

May 29, 2009 | 1987 Ford Ranger

1 Answer

My van makes clicking noise when going uphill & and sometimes the speeds slows right down and makes noise (clicking under vehicle).


Could be front CV axles making that noise. Check out the rubber cv boots going from the transmission to the center of the front wheels, If the boots are ripped or cracked, replace the cv axles on both sides.

Apr 22, 2009 | Dodge Caravan Cars & Trucks

1 Answer

1994 Dodge Caravan transmission


You should add enough fluid to register on the stick. Just add 1 quart at a time and check the stick.

Don't assume that the torque converter is completely full.

Once you are up to the proper level, test to see if it goes forward and backward OK.

Hopefully the transmission is OK after being possibly run with no fluid in it.

Let the vehicle sit and idle and look on the ground for leaks, watch for the hoses that go to the radiator as they are prone to leak sometimes.


Apr 15, 2009 | 1994 Dodge Caravan

1 Answer

1994 BMW 540i does quick, short, unexpected downshifts


Dear sea_lion42, Friday 2-20-2009 11:22pm EST (USA)

Check your transmission fluid which is usually done with the engine warm and running!
If the tran fluid is low add some Lucas Trans Fluid from your local auto parts store!
The knock makes me believe your low on trans fluid!

jack
3437e84.jpg

Jan 23, 2009 | 1994 BMW 5 Series

2 Answers

2001 Buick Regal, 3.8L, 98,000 miles: Car will not go past 55 mph, it seems to lose power. If I try to accelerate to go faster, the rpms go from about 2000 to 3000, but the car does not go faster. If I...


This happened to my 2001 Regal... There is a factory recall on the Catalytic Converter going bad. I had mine replaced with the recall and haven't had a problem since

Jul 15, 2008 | Buick Regal Cars & Trucks

Not finding what you are looking for?
1994 Oldsmobile Silhouette Logo

Related Topics:

249 people viewed this question

Ask a Question

Usually answered in minutes!

Top Oldsmobile Experts

yadayada
yadayada

Level 3 Expert

75822 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22156 Answers

Jeff Turcotte
Jeff Turcotte

Level 3 Expert

8211 Answers

Are you an Oldsmobile Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...