1999 Camry 3.0 V6 Motor revving up when acceleration

[elbowyer]

This is a Camry 1999 3.0 with a 5 speed w/95,000 miles. The clutch has been checked and is in good shape. Sometimes during sharp acceleration at about 2200rpm it will hang there a second and jump to 2600 and drop back down. Feels like a clutch slip but that is not the problem. I just changed plugs, wires, fuel filter, air filter and TPS. No codes tripped and it runs great, plenty of power, idles great. It is not a huge drivability problem just irritating. It only does it if the acceleration is just right. This is my daughter’s car and has owned it for years and all scheduled maintenance has been done. Any help would be appreciated.

[The7]

Has the clutch been replaced?

[elbowyer]

No But had it checked by Toyota and myself and it is fine. I can put in 3 gear and start or it will die on flat. same on a hill even with emergency brake on. It will only tend to do it when you get on it in a high gear. If you drive relatively normal it will go for days and not do it. It will just go up a few hundred RPM and right back down.

[93celicaconv]

Is there a physical engine speed increase when the tach goes up suddenly, or is the engine running normally but the tach is displaying something abnormal?

If the engine's physical speed actual does increase, and assuming the wheel speed does not increase, then something is slipping. And since everything is gear driven (and you would know if your were starting to skip gears), then there is only one place in the drive train where there is a possibility for slipage - that would be your clutch.

How do you know your clutch is good? By checking on the friction thickness? If you have a rear main engine seal leak, are you maybe getting a little oil on the friction surfaces? Is it possible your clutch isn't fully engaging, or is your clutch pedal not fully extending?

[camry6]

There is a also a possibility of weakening clutch holding springs. Even if the disk looks O.K, the clutch springs that clamp the friction disk may be getting weak (possibly caused by overheating the clutch) or may have some springs broken. This will weaken the grip of the friction disk to the flywheel and allow slippage.

[elbowyer]

I took it to Toyota and they test drove it. I can put in 3 gear on a hill and either get it to move foreward with enging rev or it will die it will not slip. There is no oil leak . It is not a true slip it is just like you get to a point usually 2200 and you tap the gas peddle for a split second in a high gear. If i want on a hill going 50mph in 5th gear the v6 has enough power that I can put the peddle to the floor and it takes off with out slipping. If it was the clutch that is where it would slip. There seems to be a split second that the fuel system does know the gas peddle has been moved and then it gets the catches up. I have a friend that has a snap-on antagonistic scanner that can be used when we drive and he should be able to pick up what is going on.

[93celicaconv]

You said in your 1st thread that the engine jumps from 2200 to 2600 RPM and then back down under a hard acceleration. If the engine speed is truly doing that under acceleration, I would say you have a true slip somewhere!