Changing the battery and low rpm when starting the engine?

Altima '05 2.5SE - High RPM After Crank Shaft Sensor Replaced?

• Feb 19 - brought my Altima in for a winter check up - tech said AVR test / battery load test failed even though NO probs starting in -40C weather; March 5 - car in again because of intermittent starting problems - Crank Shaft Position Sensor replaced - no more starting probs but car is running 200-300 PM higher are 50-60km/h (30-35mph) speeds and well over 600RPM at 100-110km/h (~65mph) on the highway; Mar 10 - brought car in again for this high RPM prob and A/T control unit replaced (TCM?) ... no improvement. Just want my car back the way it was before I brought it in on Feb. 19th! Recently, am now experiencing the following: 1) Car starts and revs at 2000RPM in Park; sometime eventually idles down to less than 1000RPM but not always; when put in Reverse or Drive at high rev it, of course, makes the car jerk. 2) After driving for even a short distance, car will rev up to 1500rpm in Park from 700-800rpm in Drive. 3) While driving, if I pull back on the gas between 65 and 75kmph (~40mph) I feel and see the tachometer drop then return to 1500RPM but it feels sluggish - like the transmission's trying to change gear. 4) Drove the car in 3rd gear (i.e. P, N, D, 3, 2, 1) and hit 4000RPM at 100kmph (60mph); felt like the transmission was not going to change gear - engine sounded like it was forcing itself during acceleration; was going to floor it to see if the over-drive would kick in but didn't for fear that something very wrong would happen. Although all tran fluid checks since Feb. looked good to me, the car was at 88,000km (55,000miles) so had a full tran sevice (inc. flush) done two weeks ago - no change in the above symptoms. Have had my car serviced at a local Nissan dealership. If they can't figure this out, then who can? And why can they not tell me when the transmission should be changing gears and what RPM it should be running at in each gear (including in Drvie, 3rd, 2nd and 1st gear)? Car is coming off extended warranty Aug. 22nd so I hope there's someone out there who can help ... and thanks very much if you can!

• Answer:

  Either there is something wrong with the transmission or there is not. ANY trans codes like TCC solenoid Valve? Torque converter lock up is the last thing the trans does. Idle learn procedure has that been preformed? Your car has several recalls and I bet you have had those preformed. Mechanically there is no way to make a car run 200 to 300 more RPM gear ratios have not changed. And 300 RPM is about how much the tach drops at 45 mph or more when in over drive, torque converter clutch engage. Only a good Nissan Master Tech should work on this issue. I hope you find the problems. IAVL first! idle air voloume learn.