99 Camry shuddering during acceleration!

[XtrueOloveX]

I have a 4 cylinder 99 Camry with about 97000 miles on it. Yesterday, it started to jump when I accelerate. It does not accelerate smoothly at all. The car starts to go, and then as I go a little faster, it starts to jump without me pushing any more on the gas. Also, I notice that the tachometer doesn't seem to be moving accurately with the acceleration of my car. I went about 50 miles an hour down a service road and as I accelerated, I noticed that the tachometer tended to stay in the same place. Could someone please give me some ideas as to what might be causing this?

[Bmaintz]

I would sugest using a concentrated Fuel Injection cleaner... I use PI from Amsoil with great success...
I also use Chevron which has a good detergent in the gas.... Of course take a look at the plugs, distributer cap & plug wires... Hope this helps... Bob

[yotatechie04]

The gen 4 runs on a "distributorless" ignition. The 2.2 litre engine has plugs, wires, and two "coil packs" located on the end of the cylinder head. Of course, as Bmaintz has mentioned, you should check/replace the plugs and wires, although the coils usually last the life of the car. You should also check the injectors, not only try and clean them as mentioned before, but if that don't help, check the polarity on them with a circuit tester, and if they don't have the required polarity, replace them. As for the Tach, you'll probably want to pull the instrument cluster and verify that all the connections are completely plugged in. Also, there is a possibility that the engine speed sensor, located on the side of the transaxle should also be checked. If the connections are good, and the sensor is in shape, then you'll more than likely need to have the transmission serviced because it's slipping. I hope that I've been of some help to you, and if you need any further help or advice, let me know. Best of luck.