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Catalytic converter & "limp" mode

Our check engine light came on and we lost power (top speed 30 to 40 mph). After engine shut off second time, was not easy to restart, but did, and then had full power again. It’s a long saga, but first told were false codes, possibly caused by cell phone signals, and that power loss was because of “limp” mode due to check engine signal. Then when we were on our way again, as soon as at highway speed, check engine recurred, and this time they said clearly catalytic converter. Questions: is there such a thing as limp mode? Can cell phones cause false codes? How do we know if we really need a catalytic converter? It’s got 129K miles.

Yes, there is such a thing as “limp mode”, and it can be experienced when the car is having transmission problems. I assume that this mode can occur in other situations also, but I have to admit that I am not sure about that.

As to cell phones causing interference with the car’s OBD system, I have to say that I have never heard of that type of situation. Knowing that people do use cellphones in cars, I would assume that the car’s electronics are well-shielded against that type of interference.

However, until we get some substantive information from you regarding the vehicle’s make, model, model year, odometer mileage, engine type, transmission type, and maintenance history, no specific help is likely to be forthcoming.

Thanks for replying. Here’s the additional info: It’s a 2001 Honda Civic LX with 129K miles, manual transmission, 4-cylinder engine, and all scheduled maintenance has been done. I can look back at records for anything specific on maintenance, but there hasn’t been anything unusual. When this occurred, we had been driving at 80 mph (legal limit!) on I-10 west of Ft Stockton – the middle of nowhere. We had stopped for about 45 minutes and started out again and this occurred about 15 miles after we started out again.