# '00 Sentra GXE High RPM Problem



## Membrane (Aug 2, 2010)

I've been experiencing what is (to my admittedly inexperienced eye) a puzzling issue with my 2000 Sentra GXE with an automatic transmission. I'm the original owner, the car has 90,000 miles, and it hasn't had any major mechanical trouble previously. I first noticed that my car barely wanted to turn over one morning after strongly starting just the day before, and thought that my battery might be on the way out. As I started driving, I noticed that even though it was idling normally, the engine could not produce any significant torque until it hit roughly 2000 RPM. In getting to 2000 RPM, the tach needle would rise quickly (almost as if the car were in neutral) until it seemed to "catch" at that magic number, and then increase at the usual rate. Further, the engine ran at a higher RPM at every speed than it normally did -- by the time the car got to 60 MPH, it was hitting about 3800 rpm, even though the engine would usually only hit 2700 RPM at that speed. Additionally, instead of slowly bleeding off revs as I let off the gas, the engine quickly drops to almost an idle RPM, even at highway speed! If I gave the car some gas at that point, the tach needle would quickly rise up to the 3800 RPM mark and then "catch," just as before. The problem is intermittent in nature. Once the car starts, the tach will either run higher than usual or not, but it will never shift from normal behavior to abnormal behavior during the drive.

I took the car to a mechanic (I also needed an A/C repair) but due to the intermittency of the issue, he was unable to reproduce the problem. He claims that the starting issue is due to an old battery, and replacing that has resulted in a strong start. He claims the alternator checks out okay. I've described to him the engine behavior, and he doesn't have an explanation for it. Does anyone here have a theory for what might be happening? Thanks for any ideas!


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## SPEEDO (Jun 9, 2003)

might start off with checking the electrical connections, wires, throttle chamber etc... (loose connections, broken wires, dirty tb)


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## jward2 (Jul 12, 2010)

1) check for diagnostic codes (let us know what you pulled)
2) check your base timing (10deg before TDC)
3) check leads for cracks/arcing points and check they connect to the cap and spark plugs firmly (dont pop up after you push them on the plug)
4) check cap/rotor for wear, damage, incorrect fitment of rotor etc
5) check there's no oil seeping through your valve cover gaskets (can cause a miss)
6) check plugs (tight, clean, gaped correctly)


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## SergioCR (Sep 18, 2002)

Membrane said:


> I've been experiencing what is (to my admittedly inexperienced eye) a puzzling issue with my 2000 Sentra GXE with an automatic transmission. I'm the original owner, the car has 90,000 miles, and it hasn't had any major mechanical trouble previously. I first noticed that my car barely wanted to turn over one morning after strongly starting just the day before, and thought that my battery might be on the way out. As I started driving, I noticed that even though it was idling normally, the engine could not produce any significant torque until it hit roughly 2000 RPM. In getting to 2000 RPM, the tach needle would rise quickly (almost as if the car were in neutral) until it seemed to "catch" at that magic number, and then increase at the usual rate. Further, the engine ran at a higher RPM at every speed than it normally did -- by the time the car got to 60 MPH, it was hitting about 3800 rpm, even though the engine would usually only hit 2700 RPM at that speed. Additionally, instead of slowly bleeding off revs as I let off the gas, the engine quickly drops to almost an idle RPM, even at highway speed! If I gave the car some gas at that point, the tach needle would quickly rise up to the 3800 RPM mark and then "catch," just as before. The problem is intermittent in nature. Once the car starts, the tach will either run higher than usual or not, but it will never shift from normal behavior to abnormal behavior during the drive.
> 
> I took the car to a mechanic (I also needed an A/C repair) but due to the intermittency of the issue, he was unable to reproduce the problem. He claims that the starting issue is due to an old battery, and replacing that has resulted in a strong start. He claims the alternator checks out okay. I've described to him the engine behavior, and he doesn't have an explanation for it. Does anyone here have a theory for what might be happening? Thanks for any ideas!


Hi!
Sounds like a transmission problem to me... have you checked the automatic transmission fluid? is it at correct levels and looks good? any noises when driving comming from the transmission?


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