2006 Chevy Trailblazer Check engine light says that the eng

what was the code??

The scanner that I have is a MAC and it did not give me the actual code number it automaticly translates it to what it says and it said Engine lean on bank 1. I am not sure why it is saying bank 1 since it is a inline motor maybe it is a default because there is only one bank. I did get a hold of my one buddy who is a mechaninc and he told me to check fuel filter, air filter if clamp on hose isn't tight & it is sucking outside air, if air filter was checked & not tightened close properly, or O2 sensor but I thought that that would give its own code.

without a number code it's very hard to diagnose the problem. I'm thinking it's a p0171 code,but can't be sure.there is some bulletins on this,but without a code it's a guess.

I will have to hook the scanner to it again when I get home and I will see if I can find the actual code number. I am sure that it is there I just do not have that much experiance with this scanner I have only had it for a few months and every time I have used it what it has said with the discription of the problem has helped me fix it. I am sorry to keep bothering you I will get the code tonight.

after you get the code just post back and we will go to the next step.

I am sorry to keep bothering you about this issue. Last night I hooked the scanner up again and I learned new things that it does. I got two codes now one more then I had the day before I also wrote down all of the freeze frame data.

P0171
System too Lean Bank 1

P0506
Idle Air Control System RPM Lower than Expected

Freeze Frame Data
Fuelsys1 CL
Fuelsys2 N/A
Load_PCT% 23.1
ETC(F) 181
SHRTFT1(%) 0.0
LongFT(%) 18.0
MAP(inHg) 8.6
RPM(/min) 547
VSS(mph) 0
Sparkadv 16
IAT(F) 54
MAF(lb/min) 0.434
TP(%) 16.9

first thing to start with is p0506,start by cleaning the throttle body.that will take care of the p0506.looking at the data for the p0171 the long term fuel trim is at +18 it should be as close to 0 as possible,LT fuel trim is what your going to keep an eye on.here are some things I want you to check. why you are checking these things I want you to monitor LT fuel trims,if they go down or go to 0 your heading in the wright direction.On rare occasions, a SES light may be encountered with a DTC P0171 and no engine performance concerns. Upon inspection, low MAF sensor grams and excessive long term fuel trims may be noted at a hot idle. This may be the result of unmetered air entering the engine due to an air intake leak, air filter concern, or air outlet duct screen damage. Inspect the AIR intake system for rolled connections, cracks, or loose clamps between the MAF sensor and throttle body and repair as necessary.
Inspect the screen that is on the inlet side of the air outlet duct for obvious damage. The air outlet duct is #3 in the artwork below.



If the Long Term Fuel Trim is consistently above 10%, temporarily remove the air filter element, reset the fuel trims, and evaluate the Long Term Fuel Trim. If the Long Term Fuel Trim remains around 0% with the air filter temporarily removed, there is an issue with the air filter that is causing lower than normal MAF readings. To correct this concern, replace the air filter. also take a fuel sample,check for water or rust. monitor 02 sensors,should be between 200mv to 800mv and should fluctuate.unplug the mass air flow sensor when it is running and see if the long term fuel trims change and go to 0,if it does not go to 0 the mass air flow sensor is not the problem.these are just some things to check,try some of these things first and post back. there are more things to check.lean codes are the hardest to diagnose.

Thanks I will try this as soon as I get home and I will let you know how it works out.

First I would like to start by saying thanks I believe that it is fixed now at least I hope. I am unable to tell 100% because I realized last night that when I cheapped out when buyig my scan tool I got a model that will not tell me live data it will only tell me the “Freeze Frame Data” at the time of the code occurring. Well what I did was first I cleaned the throttle body and I will tell you that it looked pretty dirty to me. Also at that time I took notice that the air duct tube and the air box area was also pretty gunked up with stuff. The night before I had changed the air filter but I did not do anything else this time I cleaned everything well and get rid of all of the gunk and made sure that everything was put back together properly. Then I dumped dry gas in the tank and topped it off with premium gas and cleared the codes. I let the car idle in my driveway for about 10 minutes then I went for about a 30 mile drive in all types of conditions city, highway, back roads, driving the right way, and driving like an idiot. Then I came home and let it cool down for about an hour and she drove it home (about 12 miles) and then she went to work with it today (about 18 miles) and still has no light. I understand that it still may not be 100% fixed but without being able to see the live data this is all I have to go off of. In your opinion what do you think the odds are that it is fixed?

I can't really say if it's fixed,to hard to tell,but if you check the long term fuel trims on the scan tool and there at 0 or close to 0 then it is fixed.if the fuel trims are still +18 0r higher it's not fixed. you have to understand that the ses light will not come on until it tested that part of the system. it could take 10 min of driving or it could take a week of driving. check the fuel trims and tell me what there at.

I have the same code on my 06 trailblazer, this may be a dumb question but when you say clean the throttle body, exactly how do you clean it? And secondly where exactly is the tb located? Im an old carburetor guy,
Thx Cory

just follow the air box,and it's connected to the end of the air box.your cleaning the throttle blade,use a rag and dragon fire or top shot.hold the blade open and spay it in there and wipe away the carbon.you can pick the cleaner up at an auto parts store. THIS IS ALSO AN OLD THREAD if you are having trouble I will help you,but please start a new thread on this.

[quote:1fad18ced6="brian 1"]just follow the air box,and it's connected to the end of the air box.your cleaning the throttle blade,use a rag and dragon fire or top shot.hold the blade open and spay it in there and wipe away the carbon.you can pick the cleaner up at an auto parts store. THIS IS ALSO AN OLD THREAD if you are having trouble I will help you,but please start a new thread on this.[/quote:1fad18ced6]

TY brian,
will start a new thread if I cant figure it out,
Cory