Questions regarding automatic gearboxes, and associated parts such as torque converters

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2
votes
0answers
154 views

Car transmission jerky downshift to 1st gear when braking to a stop

I have an Automatic transmission 2002 Nissan Maxima and want to know if a faulty vehicle speed sensor can cause a car to lurch forward when braking. If I am travelling at 40 mph in 3rd gear and then ...
8
votes
1answer
53 views

2005 Mazda 3 at warning light at cold start ups

I've noticed recently that my mazda 3 on cold starts would show the at warning light. When I start it, it normally flashes it for a few seconds then disappears. Then when I pull it out of the garage, ...
5
votes
0answers
30 views

what would cause lack of movement in the gas pedal, causing slow acceleration?

I have a 2002 Hyundai Elentra. Until yesterday every thing was fine. Yesterday I noticed the car was not accelerating normally. I also noticed my gas pedal basically had almost no movement. No ...
9
votes
3answers
14k views

What disadvantages a car with 4-speed transmission have compared to 5, 6 or 7 speed with similar engine?

This seemed to be most relevant site to ask my question. I am planning to purchase a new car and my shortlisted car has 4 speed automatic and 1.6 litre engine. The thing that worries me is that it ...
22
votes
1answer
3k views

What's the Purpose of Park on an Automatic Transmission?

When one wants to park a manual transmission (MTX) vehicle, one puts it in neutral, and engages the emergency / parking brake. With an ATX vehicle, the practice I've learned is to put it in Park, and ...
1
vote
1answer
32 views

Honda oydessy year 2000 does not go in reverse does not go forward but you can drive it in netural [closed]

I have a 2000 Honda Odyssey that only drives in neutral; no reverse or forward. What do you think is wrong?
6
votes
1answer
57 views

How come gears don’t normally change in an automatic car?

I know that there is a similar question here, and another one here that asks when an automatic gearbox knows how to change gear, but I want to know exactly how it does that. It was brought to my ...
2
votes
1answer
146 views

Engine sound rumbles/grumble noise 800-1300 RPM

A 2000 Toyota Celica GTS 225k miles engine makes a mild rumbling/grumbling rough sound when accelerating slowly from a stop in drive or reverse only in the 800-1300 RPM band. Does not occur when in ...
5
votes
1answer
28 views

Motor and radiator problem will there be and damage to motor or anything [duplicate]

Hi guys ive got one question i was looking over this car i was going to buy and there was engine oil in the radiator i ask the guys why it was in there he said he didnt have enough coolant to fill it ...
7
votes
1answer
37 views

My rpms are going high and my mph take a minute to go higher on my GMC Yukon

When I put my truck in drive and step on the gas the RPM's go up to 3,000 but my MPH will stay at 10-15 When I let go of the gas a little bit I can feel the truck kind of pull and the RPM's will go ...
6
votes
1answer
43 views

2000 Celica engine dies or shakes when I pump gas

I have a 2000 Toyota Celica. At first it used to slip gears and then I had a mechanic check it out. He said its a solenoid in the transmission which he changed. The car sputters sometimes when at ...
13
votes
1answer
799 views

What is a governor and what is it used for?

I was watching a classic car restoration program on YouTube in which they were working on a '50s Cadillac with an automatic transmission. The mechanic in the video diagnosed a transmission glitch as ...
4
votes
1answer
24 views

Odd Transmission slip

My transmission gets these odd slips every once in a while. For example, today I was driving slow through town, I believe in second gear, and my foot was very light on the pedal. As I release the ...
6
votes
3answers
2k views

What determines when an automatic transmission shifts?

I'm working on developing an automatic bicycle (mostly microcontroller based) and I'd presume I'd be shifting in a similar way to a car. So my question is, what factors does the transmission take into ...
3
votes
2answers
539 views

How to know when automatic-transmission box needs to be changed?

My friend is very odd: this thread about durability comparison between automatic/manual durability meant to him that manual is always better option because you can learn to change the clutch and only ...
18
votes
8answers
125k views

What's the point of the D3 gear in an automatic transmission?

My Honda Civic has a D gear and a D3, which apparently prevents it from going into 4th. Why would I want to do this? What is it good for? Does it make my fuel efficiency better or worse? Does it ...
5
votes
1answer
40 views

Engagement delay when shifting from neutral to drive or reverse

My 2001 VW Eurovan (T4) has automatic transmission and about 160k miles on the clock. When I use the transmission selector to move from N to D or from N to R, there is a noticeable delay until I feel ...
4
votes
1answer
54 views

will not start, when I just had driven it about a hour ago

2003 grand am 4 door automatic,everything works, lights, radio, windows,buzzes when key is in ignition. I hear nice noise, if it was the battery all the other things in the car would not work. What ...
4
votes
1answer
20 views

How does PCS on 4l60e work?

Looking at the pinout for the connector for the 4l60e there are 2 pins for the pressure control solenoid. 1 pin for HIGH, and 1 pin for LOW. Does this mean the PCS can only ever be in 1 of 2 ...
4
votes
1answer
26 views

1994 Silverado not accelerating past 35

I have a 1994 Chevy Silverado. On my way to work today my truck would not accelerate past 35 mph but was revving high rpm's. I stopped and checked my fluids and my ATF wasnt showing anything on the ...
5
votes
0answers
46 views

Th400 Transmission help

I pulled my Th400 out of my K20 Chevy and I'm in the middle of rebuilding it and I was resembling it and when I went to put the completed gear train assembly in it and the center support assembly gets ...
3
votes
4answers
1k views

RPM jumps up & back down at 40mph

My question is for a 2006 Dodge Magnum, 2.7 liter engine. Just over the past month or so, I noticed when I'm cruisung, just coming from a dead stop, when I'm at 40 mph my car kinda feels like it ...
15
votes
4answers
951 views

shifting stops when critically low on gas

I have a 1999 Dodge Dakota. It is a V6, 3.9 Liter, auto transmission. I have a weird problem that no one has been able to answer for me. HOW I CAME TO REALIZE THE PROBLEM: One day I was driving ...
3
votes
2answers
36 views

Mazda 3 2011 1.6 Lts Gasoline - ECU

I was wondering if its possible for a Mazda 3 2011 AT car to function without ECU? The reason I am asking is When I start the engine, the CheckEngineLight doesnot come at all When I took my car for ...
4
votes
1answer
125 views

2002 Subaru Legacy, Grinding Sound

Just got home from work and put my car into park and heard a grinding sound. The parking brake stopped working. I tried putting it into drive and got the same grinding sound. It was as if something ...
4
votes
1answer
69 views

2004 Ford Explorer accelerates too quickly from idle

I have a 2004 Explorer/v8/4wd/bauer edition. When I take off from a stop, there is a slight lag and then the vehicle over accelerates (sort of "jumps" off the line). If I gradually apply the ...
5
votes
1answer
133 views

Car cranks but will not start after transmission replacement

The 2006 Infiniti G35 would crank but not start after a transmission replacement. I found 2 transmission codes. U1000 which is a CAN bus code and P1815 which is the manual shifting code. It is an ...
6
votes
1answer
171 views

Excessive Vibrations in Drive when holding down the brakes

I'm working on a 98 Mazda 626 GF 2L with an automatic transmission. While I'm used to driving manuals, I would say that the amount of vibration when sitting stopped in drive with the brake on seems ...
5
votes
1answer
96 views

GF4A-EL Transmission Flush

I just got a 98 Mazda 626 2L and need to flush the atx fluid, it's really dirty brownish red, but not burnt and I didn't notice any particles in it. I think the car has a CD4E tranny ( it turns out ...
7
votes
2answers
61 views

Normal Operating Temp for an Automatic Transmission

While I was able to find information on testing the ATF temperature sensor in the GF4A-EL manual I've got: I was unable to find any info on the normal operating temperature of the transmission. ...
3
votes
1answer
85 views

Transmission sometimes downshifts forcefully with a clunk when I let off the gas 2003 Dodge Grand Caravan

As the title mentions, I have a 2003 Dodge Grand Caravan, and my transmission sometimes downshifts forcefully with a clunk when I let off the gas. It will do this no matter what gear I'm in (except ...
1
vote
1answer
56 views

'95 Chrysler Lebaron Shifting

I have a 1995 Chrysler Lebaron. 3.0L, V6, Automatic transmission. It has recently developed an issue where as you accelerate, it seems to get "stuck" in third(maybe?) gear. It will drive with that ...
1
vote
1answer
121 views

How to identify transmission issues

I have a new Camry L (4 cylinder 5 gear)with about 6k miles on it. Whenever I push the car from 0 to 30 mph and then let go easy on the gas to keep the car at 30-35, then I can feel the car 'jerking' ...
7
votes
1answer
179 views

What should one do to reduce the HP lost at the wheels on an automatic transmission?

I have a 1990 Toyota Supra Turbo 4 speed auto. I've done some research about automatic transmissions and manual transmissions and what are the positives and negatives of each. (For example, MT is said ...
2
votes
0answers
61 views

2000 mustang v6 3.8l tapping noise camshaft sychronizer bearing or timing chain? [closed]

My car makes this tapping noise (chain like tapping noise) and (most noticeable) when driving up hill, or at low speeds under a load. Another that has started to happen after this issue, is a type of ...
6
votes
1answer
38 views

Will increasing line pressure increase torque capacity?

I was wondering if one were to increase the line pressure sent to the clutch packs/bands on an A/T would that increase the torque capacity of said transmission? I figure it would because it would ...
4
votes
1answer
69 views

1999 Mazda 626 Auto Transmission Starts in 2nd, wont shift past 3rd

My wife has a 1999 Mazda 626 that had the transmission rebuilt 5 or 6 years ago. Recently the car started having problems starting unless it was shifted in to neutral. I replaced the neutral safety ...
0
votes
1answer
47 views

How to get in fourth gear

I have 2007 automatic Scion tC that I just bought and I was wondering how do I put it in 4th gear or (sport)?
4
votes
2answers
3k views

Do I need computer reprogramming when transmission is replaced?

Honda Odyssey 2003: I'm replacing a transmission, and a local mechanic will help me to swap it in my garage. I've been told at a local shop, that in order to install remanufactured transmission ...
1
vote
2answers
114 views

Location of fill tube for Nissan Pintara auto transmission fluid

Where on a 2.4lt 1989 Nissan Pintara do you put the transmission fluid? I cannot seem to find where it would go and my vehicle is not changing gears properly.
1
vote
2answers
3k views

What does PRNDSB means?

My Daihatsu Mira does not have any manual, Its an automatic car with TurboEngine and Gear with PRNDSB. What does all these means? My car is four wheel drive as I can see rear differential in it. If ...
4
votes
1answer
56 views

Automatic Transmission - Reverse Flush, what is this procedure and why is it dangerous?

I recently, moments ago, saw in a post a mention of a reverse flush in reference to an automatic transmission fluid change. The responder mention the dangers of a reverse flush and that many of the ...
2
votes
0answers
36 views

Transmission Fluid Change - High Mileage Vehicle [closed]

Should I replace the ATF in a 2007 Honda Odyssey w/ 208,841 miles? Numerous shops advise against drain/ refill. I last changed @ 144k & was advised not to do it ascI could encounter transmission ...
6
votes
7answers
38k views

Strong vibrations when idling even after replacing engine mounts (automatic transmission)

I have a '93 Acura Integra with automatic transmission. Ever since I got it some time ago the car has been vibrating a lot when stopped at a light, for example. The vibration is worse when in gear ...
3
votes
1answer
292 views

Pulley Difference After Drive Belt Change

I have one worry after yesterday's fairly difficult but successful drive belt change on my Big Boy scooter. The main nut on the fron pulley now goes on much less further than before it came off. I ...
1
vote
1answer
49 views

What is happens to the brakes when an automatic drives below the speed for 1st gear with no added gas?

In a manual transmission car, when a driver wants to go below the speed the car travels at in first gear with no added gas using the gas pedal, you ease off the clutch, reducing the amount of power ...
1
vote
3answers
681 views

Toyota Corolla 2011 not accelerating when on 60mph or above

I recently bought a toyota corolla 2011 s from a local dealer with 80,000 miles on it. In my test drive everything seemed normal and was satisfied with the deal. But on a recent trip when i actually ...
2
votes
0answers
39 views

While in Drive, transmission failed to engage after stopping at light

I have a 2011 Nissan sentra. MESA remote start installed 2 weeks ago. It all works fine. However, last night stopped at light, went to go, and it's like neutral and the engine derates. However I don't ...
4
votes
1answer
65 views

Banging sounds coming in front of my car

I'm having a banging sounds coming from the front of my car. Usually they appear after 5-10 meters when I'm driving. It's like one small knock and then around 5-6 more knocks and then they stop until ...
4
votes
1answer
1k views

2001 Mercury Sable — Rough Idle/High RPM and Transmission Leaks

I have a 2001 Mercury Sable (24V DOHC V6) that has been having problems with its vacuum system. I live in Florida where the average temperature lately has been in the 80s. For roughly a month now, ...