Question about 2004 Chevrolet Silverado 1500 Crew Cab

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2004 chevy silverado

When i start my truck it says reduced engine power across the dash. when i step on the throttle it does not rev up. Last night the check engine light came on and this morning it was still on, I disconnected the battery, checked all fluids and the light was still on. I checked a few electrical connections to see if they were tight and one under the hood on the firewall just above the steering column clicked and when I checked the dash the light was still there and the message center reads reduced engine power. when I press on the gas pedal there is no power. Engine idles smooth.

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  • xlr8nxs Oct 19, 2008

    After disconnecting the battery cable and removing the 2 connectors plugged into the bottom of a module located under the hood in the upper drivers side corner of the firewall near the hood hinge. I cleaned the connectors and receptacles in the module with compressed air and re-connected them. I feel the connector that was loose was the culprit. I started the truck and the check engine light was still on, but the reduced engine power was no longer displayed on the message center. As I backed out of the drive, the check engine light went out and stayed out so far. I'll update with any changes. Pretty sure it was that connector being loose. Wonder if that connector being loose may have been the reason for occasional erroneous tach readings. We'll see.

  • xlr8nxs Oct 19, 2008

    Removing the power from the battery and then removing/re-connecting the plug (there are 2 plugs into the module, the one on the left is the culprit) at the firewall connected to the module just above the steering column and next to the hood hinge on the drivers side before re-connecting the battery is what fixed the problem. We tried the same thing on my dad's 2006 Silverado crew cab and had the exact same results.

  • gdsdickens Apr 18, 2009

    Yes this is the problem I have also, When the check engine comes the dash that means it has set a code. The code probably be either P1125, P2120 or P2125 now the the first code deals with the APP system which is 2 sensors in the fuel pedal which is the Accelarator Pedal Position and the TAC module which is the trottle acturator control which is under the hood on the firewall between the brake booster and the left fender and the throttle position sensor TPS on the side of the throttle plate. The other two codes are set when you are running the vehicle and unplug any of these conponents. These three the APP, TAC and TPS talk to each other and when you break the loop it sets the 2120 and the 2125 code. Now I have talked and researched this problem to no end but what have found out is this problem is a intermitent problem which means it can come and go. You can tell you this I have replaced the APP sensor it ran fine for about three weeks and came back and By unhooking the battery sometimes works for awhile all this does is reset the PCM. What I have found also that the intermitent part deals with the connectors and poor connections but if you clean tese connectors you still have to have the codes erased with a scan tool Advance Auto can do it. I don't know if helped anyone because I am still suffering from this anoying problem. By the way dealers have no answers also the after market scan tools pick the P1125 code up as a Fuel & air metering which only means that the computer has pick reduction in fuel and air causing the reduced engine power. I am investigating this problem and any help will be welcome and if I find the problem will relate it to you. Thanks

  • myra moore Mar 27, 2013

    This is exactly what I am dealing with. Mechanic still researching. They also gave me the dme codes.


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The above descriptions of the connector are very good. I washed the engine compartment yesterday, and immediately started getting the reduced enginer power code on the CIC, not performance. After reading several posts, I checked the connector on my 2003 2500HD, and found that the connector was not seated well and had gotten water in it. I cleared the water and the reconnected. The cables running from the fuse box to the connector are so short, the connector is in a bind and is pulled off-center. That is why the connector wasn't seated properly. The code went away, and the performance returned. By the way, be sure to do this after pulling the negative cable on your battery.

Posted on Apr 30, 2009

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SOURCE: 2004 chevy silverado

My Dad and I both had the same problem. All he did was stomp the gas pedal fast and hard and it fixed itself, mine I had to replace the pedal sensor.

The pedal sensor cost about $50.00 and you can do it yourself. You will need to remove the gas pedal (it is only 2 screws) and unplug the pedal sensor, you will need a star bit with a whole in the center ($2.00 and you can buy the set anywhere) of it. This fix is very easy and it should only take you about 20 minutes to complete.

All the Best

Posted on Feb 22, 2009

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