Reduced power turns on when idling

Both check engine and reduced power light constantly coming on, I lose power while driving and can only go about 35mph. Have had both catalytic converters checked, MAF replaced and put back, both TPS' replaced and still have the same problem. At first the same three codes would show up p1515, p1125, and p1295. Then the other day while running the car it began to shut off by itself every once and a while. Then all of a sudden it went from the same three codes to 12 codes. Disconnected battery and when lights came on 15 codes appeared, then when we did the same thing 20 codes appeared. If given a day the car will run fine for about thirty minutes then check engine light and reduced power again. What could the problem be? Could it be the wiring? Or could it be that I need a new computer? Can I get the computer checked out somewhere?

I googled the three codes for you and this is what came up. I recently had the same problem with my wifes car and we replaced the TPS and it runs just fiine. The TPS is a dealer only part which costed us 150 bucks. Hope this helps.

We thought it was that too but when we replaced the TPS the car still had the same problems. If I let the car rest a few days it drives fine for a day then after that back to reduce power and check engine. It's as if the longer it rest and no one drives the longer it will go without messing up sometimes it will last 2 to 3 days. Does anyone have any other suggestions?

My car is doing the same thing I need help to what is it?

The Check Engine light and the reduced power light both come on and the car will only move about 1 mile an hour, it just inches along until I get it home. I took it to 2 mechanics who said it might be the catalytic converter but it has dual converters and they could not tell which one. I took it to a muffler shop and they said that the dealer had put a chip in and their diagnostic equipment could not read it to determine the problem. I took it to the Izusu dealer and they kept it the first time about 6 days and said they could not find out anything becasue the lights would not come on for them. I brought it home and drove it from March to this month May 5th when it did it again and the dealer had it towed to the dealership on May 5th. When they finally looked at it on May 8th it was not doing it, so they still have it there. Any suggestions?

The Rodeo is still with the Dealer's service department. If I get it back and it is not fixed then I will follow your advice.

My rodeo is doing the same thing and has been for 5 years. No one seems to know. I have had diagnostic testing done and expensive repairs because of this and still having issues. It is currently parked because I am scared to death it will konk out on the highway. I does not happen all the time but when it does it is non stop. Need help please if anyone knows, It sounds like a sensor to me and it is not the engine despite the light on.

One day I was driving my vehicle taking a friend to work. It began to jerk all of a sudden and the Reduced Power light illuminated on the dash. I began to lose power. I went to my local mechanic that I trust and they stated that it was the fuel pump. Not knowing that I have 2 fuel pressure pumps in my vehicle, I got the one in the tank done. I was told later on that it was the High Fuel Pressure Pump. Could this be the cause of my Reduce power light staying illuminated? And what could the other causes of code p1239 mean for my vehicle listed above?

Check engine keeps lighten and go off from time to time, if it is on the speed cruise does not start and the reduced power lights on long stops or when you put gear on D while care is stopped.

The computer scan code is p1239, I still have the problem and I have tried almost every thing but now the check engine is almost on all the time and when ever I stop reduced power lights as well, I have noticed that when the car fuel level is low (fuel light is on) check engine light goes off for some time.
Any body have anu idea?

When I clear the code it will accelerate but not running well. The code is not in my book can you tell me what the means? This is the code P1239.

I replaced that pump and no I am not a mechanic. I am an auto body mechanic and I work on the lighter side of mechanical.