My Audi A4 has a bad transmission range sensor and when accelerating the car shakes, I don’t know if it’s the sensor?

ANSWER : A faulty transmission range selector switch/sensor could have some negative effects on vehicle performance and consequently the switch should be replaced prior to a diagnostic for the acceleration problem you are describing. After the sensor/switch is replaced, if the acceleration problem remains, that problem would be identified and resolved during a slow acceleration diagnostic. To obtain replacement of the range selector component, please use YourMechanic’s transmission range selector service page and the responding certified mechanic will get this taken care of for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

ANSWER : When you say you have three bad sensors I can only assume you have had them tested and the end result is three bad sensors. If they tested bad then they should be replaced. The power steering sensor senses the load of the steering on the engine so it can raise the idle during parking maneuvers. The O2 sensor is used for fuel control and it may effect engine power and fuel mileage. The camshaft sensor cay cause no starts, engine running problems and all three will turn on the check engine light.

ANSWER : It is very possible that you have a valve cover gasket or spark plug tube seal leak on your vehicle. These type of leaks will allow oil to leak onto the spark plugs causing misfires. When the engine misfires due to oil getting on the spark plug, the engine oil will burn. Since oil and tires are both petroleum products, they will both smell similar when they are burning. I would recommend having an oil leak inspection performed by a qualified professional to determine if there is an oil leak. Consider YourMechanic as an Oil/Fluid leak inspection can be peformed at your home or office.

ANSWER : Hi there. It depends on whether or not you are racing your friend on a NHRA sanctioned Drag Strip or illegally on the street as to whether or not the O2 sensor is causing you to be slow. If you’re racing on the street, the O2 sensor is fine and has no impact. If you are racing on the drag strip; yes – a faulty O2 sensor will cause poor engine performance, reduced fuel economy and other problems. Two pieces of advice from a Licensed NHRA Drag Racer, first, KEEP IT ON THE TRACK; not the street. Second, have a professional mechanic complete a check engine light inspection to tell you what O2 sensor is faulty, have it replaced and reset all error codes.

ANSWER : Hi there. The description you have given, leads me to believe you have a combination of faults. Assuming you have already checked the basics (back-up light bulbs are good), (the fuse is good for the back-up lights). A circuit test needs to be done to confirm no power supplied by the back-up light switch to the light bulbs while in reverse. This can be done, key on engine off, parking brake set. The vehicle dropping out reverse into neutral could be a range sensor issue. A scanner capable of reading the transmission range sensor would be required to identify whether the transmission control module is being commanded to neutral. Low transmission fluid pressure in reverse could an issue. Replacing parts without confirming the diagnoses could be expensive and not fix the problem. I recommend the transmission range sensor be inspected by a certified technician from YourMechanic.

ANSWER : Hi, thanks for writing in. The transmission range sensor switch must be physically aligned with the gear selector in order to work properly. This generally involves putting the shifter in the Neutral position, then adjusting alignment of the range sensor switch to the default Neutral position. If they are not aligned, the transmission controller will detect mixed signals from the range switch and the transmission internals – resulting in the P0707 you see. It is also possible that the wiring harness to the range sensor is shorted, or has a poor connection somewhere in that segment of the wiring harness. I would recommend having YourMechanic.com diagnose this issue, provide an accurate assessment of damage, and estimate the cost of repairs.

ANSWER : If it doesn’t run for more than about a minute, that could be a normal situation. The fan is triggered by temperature at the cylinder head, and when the engine is off and the coolant isn’t circulating, the heat rises to the top of the engine. If the car is fully warmed up and it’s a hot day outside, the fan may come on for a short time when the car is off. If it runs on and on, it may be a different matter and you will want to have it checked out.
The leak, should concern you. Left to themselves, things always go from bad to worse and it could get worse at a very inconvenient time. If you contact Your Mechanic, they can send a technician to your home or office to check out your Honda and let you know what can be done for it.

ANSWER : Hi There,
This is a known issue in this generation Ford Focus and some Fiestas with the "Power Shift" transmission and there have been numerous recalls and lawsuits. Although, it is would be difficult to determine how much longer your transmission will last given the fact that you have many new parts, I would not recommend junking the car as it may still provide some valuable life left for you. I would recommend taking it to the dealer to see if these parts may be covered under the recall.