2500 RPM rev limiter?

I am posting this question for my son. He has a 1995 Tacoma with the 5VZFE engine. He doesn't drive it regularly. He lives in CA, I live in AR. I just returned from a visit in September and we drove it around several times and it ran perfectly, just as it has for the last 20+ years he has owned it. Just recently, he needed to use it and when it got to 2500 RPM, it refused to rev any higher and sounds and acts just like it hit a rev limiter. He first thought it was the clutch shuddering but after closer examination, realized it was the engine. He and I are at a complete loss as to what it might be, what might have caused it. Can anyone shed some light on this situation?

Many thanks for a suggestion or a solution!

 

First thing I'd do is pull the negative off the battery for 10 seconds, put it back, and see if it still does it. That'll rule out a few things

 

Will do and will let you know.

 

He did as you suggested and now it will rev to 3000 before it hits the rev limiter. Any ideas/suggestions?

 

If a check engine is on and the engine will only rev to 2500 -3k rpm the ECU is limiting engine rpm to protect it from further damage . This is more commonly called " Limp mode "

 

Usually this suggests some sort of ignition failure. I don’t remember what ignition system these had in 1995, but I would test the coil(s) and distributor.

 

A bad camshaft sensor or crankshaft sensor or bad wires or connectors will cause this too going to the sensors

 

Blockage in the cat or muffler.

 

Thank you. I neglected to state in my original post that no engine check light is on or has come on. It seems every thing is normal except for the strange behavior of the rev limiter. Starts and runs perfectly, it just won't rev. It was normal one day, next day the issue arose. The no check engine light has both he and I puzzled.

 

X2 yup clogged cat will do this too

 

Thanks all!
I will have him check the cam and crank sensors and also the exhaust system.

 

Check the plugs. check wiring for mice, etc.

 

Would not the cam/crank sensor wiring or the CAT create a check engine light? My thoughts are if the CAT were clogged, it would throw the O2 sensor readings off and create a check engine light. When the rear CAT went out on my Nissan the check engine light came on and same with the knock sensor and same with the O2 sensor. I'm just puzzled at the fact that no check engine light has come on on his truck. In any event, he is going to have the CAT checked first as it seems to he and I to be the most likely suspect. Thank you all for the suggestions! You are much appreciated!

 

Typically it would but not always on the sensors.
My crankshaft sensor didn’t, my camshaft did when I was switching to standard alone ecu

 

Start with exhaust 1st because it should be easier