My altima won't get rpm above 2500 and it bounces i replaced the tps and the problem is still there i have been told that the catalytic converter could be blocked up

Test for shorted electrical wiring or open .
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first check your fuel system, replace fuel filter, also check your fuel pressure regulator on your fuel rail it may be leaking internally if ok check your fuel pump operation. if your fuel system is ok then check for a restricted catalytic converter its a common fault I encounter with them. if that to checks out ok then have the ecm scanned by a shop or the dealer could be a faulty engine speed sensor or crank or cam sensor

clogged catalytic converter

Hi looks like mine problem.looking for ideas.Crankshaft sensor or TPS sensor[RPM].I swapped coils and module.No light and what it is?

There can be more than one sensor in the system. But here is what happens when your old sensor goes bad. The fuel mix can go rich and this results in a buildup of soot in the catalytic converter.

Sometimes the catalytic converter can recover over time. There are cheater additives which go in the gas and may help you pass the test.

You need a better diagnosis of your potential problem. The onboard computer in your van will not Code every problem and has to be showing a "check engine" light to display any problem.

However, better Scanners (Some costing thousands) can probe the system and reveal many defects.

New sparkplugs, clean fuel injectors, can help lower emissions. Just remember that an additive which dissolves debris on fuel injectors can also send that debris to your Catalytic converter.

Now as far as running it "forever", you want highway speeds, which in terms of RPM is about 2000 RPM on many vehicles. You can shift out of "overdrive" and this will keep the RPM higher at a slower speed, but it needs to be above 45mph to be effective. Your overdrive does not always kick in below 45, so to make a difference using my tip would require driving above 45.

It could be a catalytic converter, fuel, or air intake issue. To test the cat. start the truck and let it reach normal operating temp. run in park or nutral at 2500 rpm for 3 min. after 3 min continue to run at 2500 rpm and measure the temprature at the front of the cat and at the rear of the cat. It should be at least 200 degrees hotter after the cat. If not replace it.

check fuel pressure and volume to make sure you are within specs.

Also on the back of the distributor is a ignition controll module that go out all the time. The have a simular reaction. If you have not replaced it in the last 50000 miles it is time to do so.
If you have anymore questions feel free to email me at [email protected]

It sounds like the exhaust system is clogged. Try looking under your vehicle with a flashlight and look for bends/kinks in the exhaust pipes. I had a similar problem with my car, when the catalytic converter broke apart, and clogged the exhaust. i could barely reach 20km/hr, and the engine would shut off at 2500 rpm. Replacing the catalytic converter fixed my problem.
Matt

sounds like a catalytic converter - runs good but lacks power - the back pressure keeps the engine from being able to accelerate under load - good luck :O)

I have had that same problem in the shop a few years ago and there were broken wires going from the body to the door inside the rubber boot.. Check there first.

The PCM is allowing torque converter slippage until the transmission reaches normal operating temperature because cold transmission fluid is a drag on the engine and causes it to burn more fuel.