QuestionQUESTION: The constant thing is it shifts from 1st to 2nd approx 3000 RPM.
When totally dead cold or having been driven for at least 20 minutes, no problem shifting into overdrive. If I drive 5 miles and let the car sit for a couple hours, it will take about 10 minutes before I shift into overdrive on the freeway.
Also, when the gas tank is low (at least so it seems), I have a loss of power on steep hills. It will sometimes rev up to close to 4,000 RPM before shifting to 2nd gear. Then when it shifts, it will be sluggish and sometimes may downshift with minimal gas pedal. It feels like there is no acceleration in 2nd if I go gradual on the gas pedal.
ANSWER: Hi Lou -
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Sounds like you have problems with your trans. Have you checked to oile level? A low oil level could cause this problem. Also sometimes if you change the oil and filter, put an additive like AT205 in there, I have been able to re-generate the trans.
If all fails, then an overhaul is needed.
Hope this helps -
aloha
calvin
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QUESTION: Oil level is fine. I'll try a fluid change (I put in some Trans Medic and that seemed to help). Since Nissan Quest has an electronic shift control and because the problem occurs when the gas tank level is low, I'm thinking other things. I have a half tank of gas right now and the only thing constant is a shift to 2nd gear at 20 mph (3,000 RPM) with moderate throttle); it'll shift at 17 mph with light throttle (about 2500 rpm).
If it gets to the point of an overhaul, the cost would exceed the blue book value of the vehicle.
If it comes to an overhaul, the cost is worth more than the blue book value.
ANSWER: Hi Lou -
Usually if it is the VSS Speed sensor, TPS (Throttle sensor, or similar it will kick the Check Engine Light on. But you never know I have had zero codes before in the past which have turned out erroneous.
Try replacing the oil as you say, and see what happens. I really recommend the AT205 additive, it has performed miracles for me in the past.
Hope this helps
aloha
calvin
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QUESTION: Is the Quest TPS a switch or a pot? That is something I can check with a meter because it looks adjustable.
AnswerHi Lou -
The TPS is a sensor and can be checked for voltage. Caution to not apply battery voltage to any terminal cause it runs on millivolts -
Throttle Position Switch1) Start and warm engine. With KOEO, check voltage betweenATCU terminals No. 14, No. 21 and ground while depressing andreleasing accelerator pedal slowly. See THROTTLE POSITION VOLTAGE TESTtable.
THROTTLE POSITION VOLTAGE TEST------------------------------------------------------------Accelerator Pedal Voltage
Released Terminal No. 14 ........................Battery Voltage
Terminal No. 21 ....................... One Volt MaximumFully Depressed
Terminal No. 14 ....................... One Volt Maximum
Terminal No. 21 ........................Battery Voltage
2) If voltage is not as specified, check throttle positionswitch. See appropriate test under COMPONENT TESTING & CIRCUIT TESTS.Check harness for open or short between ignition switch and ATCU tothrottle position switch. If within specifications, perform self-diagnosis again after test driving vehicle.
