Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum banner
1 - 8 of 8 Posts

·
Registered
Joined
·
5 Posts
Discussion Starter · #1 ·
I have an 03 TB with about 120000 on it. We've been fighting this problem for about 3 months now. The Reduced Engine power light comes on and the SES light. We have to restart to clear it. Originally we had 5 codes, we've had all of those fixed. (I can't remember all the codes, but it include the APP and the TP and our last code was for the thermostat). We just recently had the thermostat and spark plugs replaced. However it is still happening. Also when I pull over to restart it after the lights come on it revs super high. Also sometimes when I first start the vehicle it revs high. The last time it happened it gave out the code 1221. We already had this fixed so we are unsure why it is coming up again. Also we have paid to have it diagnoised twice and after all this time and money it's still happening. Any help/advice would be greatly appreciated. Oh and on a side note we have smelled a sweet smell sometimes when driving/starting the vehicle even after the thermostat has been replaced. Please help!
 

·
Registered
2003 chevy trailblazer_ls
Joined
·
5,268 Posts
did you ever have the accelerator pedal replaced..
the sensor on this goes bad-- and sometimes work- and sometimes doesnt.
when it doesnt- it sets the reduced engine power light..... thats one of the causes...


since youre smelling sweet stuff...
either its leftover residue from the coolant that was spilled from the thermostat change....
or its leaking.
Pop the hood- and make sure the coolant overflow bottle is at the COLD line when the engine is cold 1st thing in the morning.
If its not- refill to that level-- that way you can monitor if its leaking.
Overnight- if you leak any fluid- as the engine cools- it will SUCK in coolant from the overflow- so if this drops- you know youre losing coolant...

Also- youre going to have to get under the truck- and look at the thermostat housing... double check that youre not leaking a bit of coolant from the O-ring on the housing--- (when installing- this tends to sometimes move- and not cause a proper seal).
You may also want to check the hose connecting to the thermostat housing to make sure it is not leaking.
 

·
Registered
Joined
·
5 Posts
Discussion Starter · #3 ·
We did have the accelerator pedal replaced. It was one of the first things we did, but if I remember right it was linked with the code 1221, which is the code we are getting now so I'm confused as to why we would still be getting that code. I printed off your advice on the coolant overlow bottle and thermostat housing and will have my husband check it when I get home or in the morning. Thanks
 

·
Banned
2004 gmc
Joined
·
26,181 Posts
I just solved another member's strange problem by having him reseat the PCM connectors. He had some slight oxidation and the voltage reading was erratic, and that can cause bad sensor readings. It's possible (but not very likely) that your new pedal position sensor isn't being seen accurately by the PCM.

Just another thing to try when nothing else makes sense.
 

·
Registered
2003 chevy trailblazer_ls
Joined
·
5,268 Posts
ill ask for her and others...:raspberry

where can one find the PCM's location.
 

·
Banned
2004 gmc
Joined
·
26,181 Posts
Yes, I thought of that as I was posting. Sigh.....

Driver's side of the engine (assuming it's the I6). Connectors held on by three 7mm bolts. The PCM is item #1:

 
1 - 8 of 8 Posts
Top