Reduced Engine Power On My 2002 Chevy Trailblazer

2002 trailblazer LS Engine Size : 6-cylender Question: my car is showing a warning light that reads, "reduced engine power" and another light that reads "service engine soon". I have no power when i try to drive my car.

I step on the gas peddle and nothing happens. How much can i expect to pay to have my car looked at and repaired?

Answer: Usually when you see the 'reduced engine power' and the check engine light on, it is most often times a problem with the throttle body. Sometimes carbon buildup may cause this problem. The throttle body on your Trailblazer is electronically controlled and does not have a cable from the gas pedal.

When there is a problem with it, the vehicle's computer will reduce the engine output so that there cannot be any accidental damage since it cannot tell how the engine is running or where the specific throttle position is when you push on the gas. You would be looking at what ever diagnosis fee a shop would charge you, this includes hooking a scanner up and retrieving trouble codes and telling you what's wrong. The throttle body itself is three to four hundred dollars. Not a cheap repair by any means, but if you want to be able to accelerate, it is a needed repair.


Chevy Trailblazer PCV Valve Location

Does the 2007 Chevy Trailblazer 4.2 liter 6 cylinder engine have a PCV valve and how do I locate?

Answer: The 4.2L engine in your Trailblazer does have a PCV valve system, but it does not have an actual valve. The system uses an small orifice in the top of the valve cover. Under the air box on top of the engine is a vacuum hose that connects to the top of the valve cover. The orifice is in the valve cover.


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Comments (16)
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  • Guest - Horace

    Reduce engine light came on then my trailblazer shut off

  • Guest - Billy nance

    Codes show that I needed to change crankshaft position sensor ans camshaft on 04 chevy trailblazer and I changed both and still has no power and shutters and does when I let off the gas. What could it b

  • Guest - Eric Urban

    Engine loss, replace your valve timing solenoid because the screens are clogged and then take off your resonator (big black box on top) connected to throttle body. Clean your TB carefully with throttle body cleaner and a lint free wipes to remove carbon buildup. Reassemble. Drive for a little while to allow computer to re readjust it's self. May have to disconnect battery first but I would try without first. Note. Solenoid isn't that hard to fix but you have to remove belt and loosen the power steering pump to get it to clear on removal and installation. Located if looking at motor on front left side stainless cylinder shaped solenoid (about 2 inches long 1 inch diameter) with electrical connector.

  • Guest - Scotty B

    Reduced engine power , I have changed throttle sensor. And just replaced all 6 plugs. So I'm curious if you have an answer as to why that friggin light still comes on.???????

  • Guest - Bigmoney

    I had the same problem after I put a new muffler on I changed the catalytic converter problem was still there so yesterday I changed both o2 sensor the one up top and the one on the bottom drove 5hr today to see no problem so far

  • Guest - Kirk Lindsay

    Will cleaning the throttle body help or is a new one required?

  • Guest - Julia

    My boyfriend has a 2002 trail blazers 4.2 6 cylinder the check engine light coke on then the water pump went out and we replaced it but now its reducing in power ??? What could be the cause of this

  • Guest - Bret

    So far, I have replaced all the following every time I got the dreaded Reduced Engine power condition. First time was either throttle Body or the pedal itself, not knowing for sure, I replaced both and that fixed it that time but the condition happened a few more times afterwards as the computer reset itself or something? whatever? it problem solved. A year later or so, it happened again and it was an ignition coil on cylinder 4 and that was an easy fix. The next time it was a plugged converter and most recently, it was a bad cam sensor, another easy fix thankfully, BUT......periodically still getting the CONDITION! and am hoping that this too is the computer resetting itself and just annoying me so we'll see! but case in point folks! I think I have replaced everything I possibly can that could possibly cause this reduced engine power condition! how many other things could it be? if you have dealt with this and not for one of the reasons I already have, PLEASE share with us because I am pretty perplexed here. Thank you

  • Guest - Betty

    In reply to: Guest - Bret

    I'm going through this as we speak. Truck stop in . how much money is this part?

  • Guest - Crystal

    I have replaced the pedal position censor and the throttle body and still goes into limp mode and warning light reduced engine power still comes on. What’s up!!!

  • Guest - Chris

    Reduced engine power light is on? This happened on a hill and truck died. It will not start now. Any suggestions?????

  • Guest - jamie

    Rossboss67@yahoo.com

  • Guest - jamie

    What was the problem were was it located thanks Jamie

  • Guest - Tony

    In reply to: Guest - jamie

    The throttle body was bad and i replaced it and did the idle relearn.now my Trailblazer is running great.

    What was the problem were was it located thanks Jamie
    <br />
    What was the problem were was it located thanks Jamie
    <br />
    What was the problem were was it located thanks Jamie

  • Guest - Tyson

    In reply to: Guest - Tony

    Iv been dealing with this for some time also. Iv changed ignition coils cam sensors. Etc. Heat makes it start. Haven't tried pedal sensor but think its else were has anyone changed crankshaft sensor?

  • Guest - sheldon

    In reply to: Guest - Tyson

    I've had the same problem for about 2 years now. Driving fine and then boom idle goes crazy stays at 1000RPM, reduced engine power, ABS/BRAKE lights come on, SERVICE BRAKE SYSTEM displays, and or it cuts off. I turn key off and start it starts right back up. Ive changed, CRANK SENSOR, CRANK SENS WIRES, CAM SENSOR WIRES, CAM SENSOR, CAM SOLENOID, THROTTLE BODY, COMPUTER change, and still same thing. Other than that it runs great. just a pain