Chevrolet Blazer Trouble Codes

caa101

My blazer is reading a PO128 code for check engine light.Does anyone know what that is?

jlflemmons

I believe that is in the coolant temperature monitoring circuit. Maybe a bad temp sensor?

atenciolm

My Blazer had a smog test and it did not pass because of the temp sensor (coolant sensor p0128 code) we purchased the part and need to find out where it is located so we can change it.
thanks for any help

repairdog

Drivers side under hood between the rear 2 plugs - see the connector attached to it. You will lose coolant when removed so make sure you refill.

rubisco

Hey All, my first post here!

So I have 2 '95 Blazers. My old one I've had for eons and although it's had some of the regular problems I like it very much. So I pick up another and it's throwing some codes but running good. They are P0326, P0441 and P1406. Now I know that 0326 is knock sensor performance and 0441 is no flow during evap purge cycle, but I'm not sure what 1406 is for. It's not in my haynes manual and I can't find much on the web for it. Some have said it's a bank 1 post cat O2 sensor thing.

Ok, I was changing the cap and rotor and noticed that some knuckle head broke off the rear stay for the dist cap screws. So I have 2 wood clamps on there. Could this set off the knock sensor? Or do these just go bad and need replacing? I'm not sure where it is if it needs replacing.

I don't know much about how the evap system works, but I heard there is a valve somewhere that can be replaced and also a canister. Otherwise this smoke test a shop can do. I just don't know where the valve and canister are located. Any ideas?

The 1406 code?

I guess I should add that the EGR valve was getting all gunked up with carbon pellets so I took the plenum off and cleaned it up real good and thoroughly cleaned the passages to and from the EGR. Then I put on a filtered gasket to stop any more pellets from getting stuck. I read somewhere that it could be that the IAC needs a cleaning too (?). I've run a bottle of seafoam through the tank and the intake and it idles very very smooth now.

repairdog

1406 is EGR. That evap can is rear drivers side way back behind the rear wheel under that shield.

rubisco

Thanks very much man. I'll take a good look at both of those and post if I still have a problem. You seem like an extremely knowledgable guy. Thanks again.

sgnobod2000

I just recently got my service engine soon light coming on. I thought originally it was bad gas because it was right after I got gas, within 15 minutes. After my store stop I added the same amount of gas from a different station. Light stays on. runs ok. Is there a manual way to get the codes on this vehicle or do I need a reader. I know my other vehicles you had to do a succession of key off etc. I would appreciate any help.

repairdog

No, need a code reader and Advance and AutoZone read for free as well as many other local stores (in hopes of selling you parts). Read it out and maybe just a simple loose cap so write the code down and have them erase it and see if it returns.

pegleg89

I get code 1406 I repaced the fuel injection spider it ran good for the few miles then started missing and 1406 code so I replace EGR valve ran good a few miles the started missing and 1406 again engine is missig and exhaust smell of unburned gas.

mitch16

Does anyone know what this code is or where the sensor is located? My Chilton is worthless!

Thanks..

jlflemmons

P0141
O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 2)

Probably in exhaust pipe just behind the converter.

bptbd

I am working on a 2000 chevy Blazer and the error code that came up was P0147. It says that it is an oxygen sensor. Does anyone know what (out of 3) oxygen sensor this may be? Thank you in advance.

lancej

I recently had my check engine light come on and upon checking it with a pocket scanner came up with a DTC P0155 (O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 1). My Chilton Manual says my 2002 Chevy Blazer 4.3L V6 has more than one oxygen sensor. My questions are

1. Is this the sensor located on the exhaust pipe near the catalytic converter?
2. Is this difficult to replace?
3. Any tips to make the job easier (special tools, etc.)

Thanks

Lance J

waynezo

Hi Lance. I think you are right about the sensor location near the converter. I usually go to Auto Zone for diagnosis and parts. They can tell you exactly where it is located and the part is about 1/3 of a GM replacement sensor. I buy Bosch replacements for my 96. It's a simple job. Just unplug it from the wiring harness and use an open end wrench. Start it up first and let it run for a couple minutes before changing the old one. This helps break the old one loose. Don't run it too long or you'll burn yourself. The new sensor usually has anti-sieze already applied to the threads. If not buy a small tube. It makes future replacement much easier.
If you have a set of ramps you can drive up on them for easier access. I usually don't use them and don't have a lot of trouble if I suck my belly in.

westcan

i have codes po131, po151, and po300
any suggestions on what I need to check?

thanks

beers

I have a 93 chevy blazer,can't really afford a diagnostic check so I had a friend do it for me at work,the codes are 32,33,35,45 can anyone tell me what they mean,please cause I can't find anyone to help me

maurerush2112

hello,
32-egr circuit
33-map sensor
35-iac (idle air control) valve
45-o2 sensor (rich fuel mixture)
sounds like you should have a performance problem. If i could suggest... IF truck is running o.k. right now, clear codes out, drive for a day, recheck your codes. you have so much going on there with the codes, and you don't know if they all came about at the same time, or not. maybe one or two have been present for weeks,months,etc. just disconnect neg. side of battery for minute or so to clear codes. then drive it for a day, making sure you start and stop engine(keystarts) approx. dozen times. have friend check codes again. it's possible that one major problem kicked other codes on, in response to the original problem(i hope your able to follow my dribble this would be the least expensive way, rather than replacing all that shows bad. it's possible not all sensors,etc. are bad...
i hope i helped.
good luck

renoky

My "service engine soon" light came on a couple of days ago and has stayed on. I tried taking off my gas cap and putting it back on tightly, but it still is on. My other gauges show normal readings and I haven't noticed any other problems yet. I live in Kentucky and do not have to test for emissions here. Could it be anything else? Any ideas would be appreciated.

maurerush2112

you need to get a diagnostic check. If you don't have access to a diag. tool, I believe autozone does that for free. Get the trouble codes stored in the pcm out so you know where to start...could be one of hundreds of problems.

roddoghd

OK FIRST CAR GAVE ME CODE FOR MISSFIRE #1CYLENDER CODE CLEARED THEN 2OR3 DAYS LATER CAR WAS RUNNING JITTERY ON THE FREEWAY AT CRUISING SPEED PUT INJECTOR CLEANER IN DROVE FOR THIRD OF TANK STARTED HAVING LACK OF POWER THEN POWER WOULD KICK BACK IN AND DRIVE FINE. I PARKED , THEN CAME BACK 2 DAYS LATER CAR FIRED ON 1 OR 2 CLENDERS THEN DIED CHECKED FOR CODES NO CODES CRANKES BUT WONT START. FUEL TO RAIL SPARK NEW CAP ROTOR PLUGS USED STARTING FLUID DOWN THROTTLE BODY NO START, NO CODES WOW I AM AT A LOSS IS IT THE ECM OR JUST THE CRANK SENSOR OR ONE OF THE OTHER SENSOR OR A COBO OF SENSORS BUT WHY IS THERE NNO CODES GIVEN

jlflemmons

Well, if the crank sensor is not working you should get a code 0335 or 0336. And if the sensor has completely died, she ain't gonna start.

skiextreme2

Hi all, I had to get through some fairly deep water (on the road) and afterwords the service engine soon light flickered a few times then shut off. I was at about the same speed as the pickup that was next to me. About four days later the service engine soon light came on and hasn't gone off. Any possibilities other than getting codes? Like maybe moisture somewhere it shouldn't be?

labowners

I have a 1995 chevy blazer that after it starts it revs up and down and misses like crazy. The check engine light comes & goes. I've already changed the fuel pump and spider injector about 1 year ago. The check engine code comes up emissions control, but that wouldn't make the engine rev up & down on it's own. It's so loud that it makes my cat converter knock. I checked it & it's fine. Anyone know what this could be? :confuse:

blockhead1

I recently purchased a 95 Blazer. The body and interior are in great shape but the transmission was bad, and it had sat up for almost four years. I got it running and rebuilt the tranny but, as soon as I drove it, the check engine light came on. I have a code scout 2500 scanner that will read both OBD1 & 2 codes but I have a problem. The computer is an OBD1 but the connector is a 16 pin OBD2 type. My scanner will not communicate with the computer, any advice?

jlflemmons

On an OBD1 system, short the A and B pins in the connector with a paper clip. Look closely and you should see the pin identifiers on the connector under the dash. This will put the system into a diagnostic mode.

The SES or CES lamp will flash a 12 (flash, pause, flash flash) three times to indicate that the ECM is in diagnostic mode. After a pause, the lamp will flash the numeric code for any faults stored. It will flash each code three times, then go back to flashing the '12" code.

skiextreme2

:mad: I get the P0155 and it says heater circuit malfunction, bank 2 sensor 1. The store sold me a $97 o2 sensor and it didn't solve the problem. It's a 2002 Blazer. 4.3, auto, 4WD.

Any idea how to figure out a problem with a heated circuit related to oxygen sensor bank 2 sensor 1. I was told it's one of the white wires but I don't have a clue as to how to check something like that and there isn't any space to chase the wire and see where it goes (that I can see). Or, maybe someone has had this problem?
It started when I went through some water that was up to the doors. The CEL blinked a few times then shut off and two days later it came on and hasn't gone off except when I cancelled it after installing the o2 sensor.
Help!

Thanks, Rick

jt122801

my service engine soon light came on i went to auto zone for a diagnostic test the codes that came up are
PO300,PO135,PO172
I changed the heat sensor the service light still apprears any suggestions

66chevytruck

I have a 2001 Chevy Blazer 4.3L 4x4.
I had some codes come up and i replace the smog pump and the drivers side check valve for the secondary air injection system. the valve burned up and so did the hoses so i disconnected everything until i got a new check valve. the pump was fine besides some debris which i cleaned out, but i hard wired it to check n it was still working. the day after i fixed everything i was driving it and the check engine light started flashing. i pulled off and shut the blazer off, turned it on n it stayed on. it kept flashing when i did over 30 mph or 1500 rpm.
the codes i pulled were:
PO102: mass airflow sensor circuit low frequency
PO141: O2 sensor bank 1 sensor 2
PO300: random misfire
PO410: secondary air injection system
PO463: Fuel level sensor 1 circuit high voltage
B2961: key in ignition circuit malfunction
CO265: EBCM motor relay circuit
CO245: EBCM Control valve circuit
CO246: "
CO251: "
CO252: "

any ideas where to start? what is necessary right now and what i can hold off on? im broke and this is my only vehicle also if you have an idea of how much the parts will cost that would e helpful.
Thank you.

johnss10

The first thing to do is to clear all these codes, and see what happens. If the SES light comes on again, read the codes again and see what youve got. Some of these codes could have accumulated over time, and don't relate to aything anymore.

gorbey

is the EGR hard to change because I have the same code come up today 1406 and the inside of the vehicle smells like gas. Now my rpm keeps going up and down.

gorbey

My check engine light came on and the blazer was running rough so I pulled in to auto zone and had them hook up the machine to it and code p1406 came up. I was told buy a dealer that it was a EGR sensor. So I have 3 questions for any one that can help me 1) will it make the rpm needle go crazy (up and down) 2) it it hard to replace and 3) where is it located?

THANK YOU IN ADVANCE
FOR YOUR HELP

jlflemmons

1. It can make the idle irratic
2. Located on the front of the engine. Go to Autozone online and you can look up the part and see what it looks like.
3. Easy repair.

beaufighter45

hey has any one had this trouble
I have checked fuses and replaced mir 3amp fuse that should run the tailgate and door lock and power mirrors as per chevy but still no go.
key fob will not open up tail gate as well.
any ideas ?
thanks
Doug

duntov

If the accessory control switches are functional, it is likely that the relay for those accessories is bad. Replace the power door lock relay because it is also common to the other accessories you mentioned. You can use Power Door lock Relay from AC Delco F1788, $42 (GM 88922752 - MSRP $78 ); Standard Motor Parts RY246, $26; or Air Tex 1R1269, $23. That relay was used on many GM vehicles with power door locks since 1980. The relay is located behind the headlight control switch cluster on a 1989 - 1995 S10 Blazer. I am not sure where it is located on other GM vehicles. If a auto repair shop replaces the relay, they will charge 1/2 hour labor cost plus the cost of the relay. That will be about $100+ total .replacement cost.

A bad relay can also cause a 200+ ma parasitic power drain on the battery even when the ignition key is off. If the vehicle sits for a week or two without being started, the power drain could completely discharge the battery, especailly if the battery is over 18 months old.

RABIII

Any idea what these codes mean and how to repair the problem?

1996 Blazer LT 4.3 190,000 miles & still runs good

jlflemmons

P0719: Do your brakelights work? This is the code for low voltage in the brake light circuit. Blown fuse?

P0753: Transmission solenoid related. How is the transmission shifting? Could be anything from a shorted harness to the tranny to a bad shift solenoid.

RABIII

p0719 - Corrected by installing a new break switch and fixing a frayed wire.

p0753 - Corrected by replacing both solenoids in trans.

$54 in of parts & $314 in labor to to pass emmisions test.

Go figure.....

Corinne1961

I've had some problems with my blazer. It started skipping/missing a little, not much. Drove it from a cold start about 3 miles to get gas, gave me trouble cranking but did eventually crank. Did this a couple times. Drove it between these events and then one day at work tried to leave and wouldn't crank again, at all. Tried a few days later, no luck. Been about 3 weeks and this morning it did crank, idled for about 15 minutes, drove it a couple blocks and parked it, shut it down, restarted it but did start hard. Talked with a mechanic and was going to drop it off for them to do the fuel pressure check and all. Cranked right up, ran a minute, then stalled and now it won't crank again.

We put a new fuel pump on it about 1-1/2 yrs ago but the oil changes haven't been kept up for the last year or so. The check engine light has been on for a long time but never did anything about it because it seemed to run fine. We are short on vehicles and I need help. Hoping it's not the spider injector. Can anyone give me direction?

Edgar4642

Sounds like your EGR valve

ppicka

I have a 99 Blazer w/63K miles when the 4 WD light came on.I went to a Chevy dealer and was told that a DTC CO323 was the problem and would cost $830.00 to fix .Additional info from dealer :Regular production option code NP8-transfer case two speed push button.Could anyone help me understand this problem ?Also if I have this fixed will my 4 WD work?? Thanks

die

Engine light on scantool code p0128.. does the engine have a mechanical thermostate or do you change the censor...

jlflemmons

Change the thermostat. Take a look at your temp gauge and I bet you are only reading ~150 when fully warmed up. I had to change the thermostat on both my Blazers this winter for the very same condition. They open up too soon and the engine never gets to 195. The pluses are that it is easy to change, a top quality (Stant) part is not expensive, and you may actually get a bit better gas mileage out of it as they are more efficient when fully warmed up.

With the engine cold, just pull the thermostat housing off without draining anything. You will have to remove part of the throttle cable brackets to do this. Once the bracket is clear, pull the housing, swap the thermostat, and put it right back together. You won't lose but about a cup of coolant. You will need to have the SES light reset. Autozone will scan the code for you, and then hand you the reader to reset the code. I think for liability reasons they cannot reset the code for you.

die

thanx for your help....much appreciated

die

I have a 2005 jimmy , i had a p0128 and changed the thermostate, was reset and showed the codes p0053 and p1133. the engine light came on a few days later.. why after fixing one code two more appear.. (two oxgen sensers were also replaced previously).. I only have 36.000 klms. I know short driving distances are harder on your car, but this is awfully frustrating...as a previous owner of a 1997 astro van, i didnt need any serious work on it untill it was over two hundred klms.. could you tell me pls tell me what i need to replace. and also do you have a 800 number where i can phone and get a service manual for my jimmy,,I had one for my van and it was one of my better investments as my hubby does most of the work thanx

jlflemmons

Both of the codes listed relate to a defective O2 sensor. Could be premature failure of one of the sensors replaced earlier, or it could be the wiring to the sensor got pulled/damaged during the thermostat replacement.

Is the engine warming properly now? As in going to 195F (90C) within a short period (<5 mins)

valleygirlkim

The code reads "Secondary air injection - incorrect flow detected...please reply if you have had experience repairing what may be causing this code to cause the service engine light to appear.

Had a complete tune up last month and soon after the service engine light popped up. I took in back in to the dealer and they changed my thermostat. Now I'm getting a PO410 code. I didn't take it in for service yet - thought I would try this forum first.

Hope someone somewhere knows - I really like my blazer but I have already replaced the trans. which set me back big time. Now it's just general maintenance but the engine light code my be another big expense.

Thank in advance for your input. VGK

die

my husband changed the thermostate first,(under a ten dollar part, we always change the cheapest part first) but the light came back on , apparently there is another thermostate censor... my engine light is off now only cause its warner out... it went off by itself after drivin it in the warmer weather... I still need it changed......good luck ...and let me no how it goes...If u no someone handy its inexpensive to pick-up a code reader...

richk28

P0410 code is the secondary air pump. This code appears when water gets in the pump and freezes. You should replace the pump and relay. The new kit re-routs the air inlet tube up next to the battery. It is not hard to replace takes about an hour. The best price I found is GMParts house ask for Gene. The kit is about half of what the dealer charges.

valleygirlkim

Your advice is very helpful. Just wanted to say thanks - I'll probably look locally for the pump/kit as I'm on the PA/Jersey border. Have a great day.

b007halen

i have a 2000 chevy s10 blazer ls with about 190000 miles. and my check engine light is on and it is an emissions code. what should i do? and also my interior thermometer reads "OC" how can i fix that?