Hey Everyone...new here! A week ago I purchased a used 2003 Blazer 4x4 LS with 74000 miles on it. I purchased off a dealer and it only had one owner but I know nothing else about the history of this truck. Paid 4K for it here in NJ. I recently had the oil changed and will be having the breaks looked at tomorrow. Today, the Service Engine Soon lightcame on and I ran it to Autozone and the device said something about a bad MAP and some other circuit problems. Is this a MAJOR problem? Is it hard to fix/replace yourself? Where is it located? Also, being that I dont know the history of the truck, what else should I replace or have checked ASAP? Thanks! Dan

 

The MAP sensor is quite easy to replace with no tools (ok, maybe a screw driver) required. It is located slightly behind and to the passenger side of the throttle body. It just pushes down into the upper intake plenum. It points towards the passenger side. Now, it really depends on what the code is in terms of whether you actually need to replace the MAP sensor or if it is something else. What was the specific code (Pxxxx)?

Did the truck come with any implied or state mandated warranty period? Even if it did not, you may want to talk with the service manager and see what they can do.

 

It came with a 1 month/1000K warranty period. Would it be best to take it back to the dealer?

Also, what else should I check or replace? Plugs, filters, etc...?

 

I would definitely let the dealership deal with the CEL. That is what the warranty period is for.

About other things to check/replace... At 73k miles, the plugs should not need replacing, but it should not hurt. The dealership should have already done an oil change on the truck. Hopefully they have checked/replaced the air filter. Aside from that, it probably would not hurt to do a transmission, transfer case, and axle service if you are looking for things to spend money on. These items will not hurt a thing and may prevent damage later on.

 

The code is P0107

Where should I start? Still on the MAP?

Thanks

 

Start here:
P0107 Explained

 

WOW...I thought this may just need a sensor replaced. I need to run circuit tests?

 

It is likely that it is the sensor, however, would you rather test the circuit and find that it is working properly first or replace the sensor, then find out that the circuit is messed up? It is up to you. I can only provide the information.

 

Thanks so much for the help. I think I will fight the dealer on this one instead of driving myself crazy and spending the money on a new sensor.

*ADDED from PM*

Hey Kyle, thanks so much for the P0107 code help. Today I purchased a new MAP sensor and will give that a try before I try and go thought the circuit tests. The dealer is not being very helpful because he said this does fall under his warentee...it figures! lol

I just purchased this truck to get my 2008 Mustang off the road for the winter. I just want to tune this truck up a bit because I have no idea when anythng was done, or if it was at all.

Would you happen to know where the PCV valve and the Gas Filter is on this 2003 Blazer? I found the MAP sensor and thanks for that info!

Thanks so much again!

PS - is there a manual or schematic of this 4.3L motor where I can identify all the locations of parts?

 

Hopefully that solves the problem. I do not know of any warranty, especially for a newly purchased vehicle, that would not cover something like this. What is to say a crooked dealer would not just clear the codes and sell the truck off, knowing that there may potentially be serious problems...

Anyway, about the other stuff, PCV valve is in the driver side valve cover and the gas filter is on the inside of the driver side frame rail right near the front of the tank.

Here is the best I can do for component locations on short notice:


BTW, a search should yield the same results... About disconnecting the battery... That really is not necessary unless the light really bothers you. After a complete drive cycle (or a few trips around town), the light should go away on its own if the sensor does the trick.