My 2000 Isuzu Trooper does the same - the reduced power light comes on, often after a hard break, and then the vehicle won't go over 10 mph. The gas pedal sometimes stops working altogether; the check engine light has been on for a year.
The scanner checks produce up to 6 error codes intermittently. Resolving those issues doesn't solve the reduced power problem. I have replaced the throttle position sensor twice, and more other parts than I can name, including the central computer. Mechanics at two different repair shops each spent a week each going through every single wire to search for a short (I live in Mexico, where labor costs are cheap enough to make this possible, and mechanics don't charge if they fail to fix the prolem). After the second mechanic located and repaired a broken wire, my vehicle worked briefly. Today the problem returned.
Many people are reporting the same problem and some solutions in the discussion thread at http://www.automotiveforums.com/t343629.html.
Check my isuzuparts.com
Check this Isuzu site: http://www.myisuzuparts.com/
How do I reset the CPU in a 1999 Izuzu trooper. After the battery went completely dead at will not start due to the cpu. (Battery now charged
Flush radiator
Check myisuzuparts.com
The oil capacity of the 1999 Isuzu Trooper with a 3.1-liter engine is approximately 5.0 quarts (or about 4.7 liters) when using a filter. It's always advisable to check the owner's manual for the most accurate specifications and recommendations for oil type and capacity.
I have a 1994 Isuzu Trooper and it has issues upshifting at lower speeds. How do I check the fluid level in the transmission when there is no dipstick?
If the check engine light is on...might be a dirty EGR valve.
The dipstick for the 1995 Isuzu Trooper is located near the front of the engine, typically on the passenger side. It is usually a yellow or orange handle, making it easily identifiable. To access it, simply pull it out, wipe it clean, reinsert it, and then remove it again to check the oil level.
check your tranny fluid first
How to check trans fluid on a 1997 Isuzu Trooper
if it is an automatic then yes, if it is a standard transmission then no