97 Blazer Idle Issues (Or So It Seems...)
#1
09-26-2012, 05:07 PM
97 Blazer Idle Issues (Or So It Seems...)
Hey All,
I have a 97 blazer and I am having a issue with the idle/timing it seems on the truck. When I first start the truck up from a cold-state it idle's rather rough and high, over 2,000rpm for a good two to three minutes.
When I put it in gear to back out of the garage it drops to under 1,000. Then seems to chug a little almost like it's going to die (and has a few times).
I am wondering if this could be associated to the following items...
1. Idle Air Control Valve
2. Throttlebody
3. EGR Valve
4. SparkPlugs/Wires
5. Cap/Rotor/Distributor
6. Battery
I have had it die on me a few times while sitting in drive at a stop light, The idle drops to below 1k and then it seems to struggle keeping the idle and then will die. I'm able to put it back in park and crank the key and it springs back to life, but never the less it's small pain, especially in traffic when you are the lead vehicle.
Please note I am new the forum and also this is the first truck that I have owned and am just getting into the mechanical side of things. So, please do pardon me if I ask stupid questions.
Thanks!
Dan
I have a 97 blazer and I am having a issue with the idle/timing it seems on the truck. When I first start the truck up from a cold-state it idle's rather rough and high, over 2,000rpm for a good two to three minutes.
When I put it in gear to back out of the garage it drops to under 1,000. Then seems to chug a little almost like it's going to die (and has a few times).
I am wondering if this could be associated to the following items...
1. Idle Air Control Valve
2. Throttlebody
3. EGR Valve
4. SparkPlugs/Wires
5. Cap/Rotor/Distributor
6. Battery
I have had it die on me a few times while sitting in drive at a stop light, The idle drops to below 1k and then it seems to struggle keeping the idle and then will die. I'm able to put it back in park and crank the key and it springs back to life, but never the less it's small pain, especially in traffic when you are the lead vehicle.
Please note I am new the forum and also this is the first truck that I have owned and am just getting into the mechanical side of things. So, please do pardon me if I ask stupid questions.
Thanks!
Dan
Last edited by dsmith225; 09-26-2012 at 05:07 PM. Reason: Text edit change
#2
09-29-2012, 07:53 PM
A 2 grand cold idle is really high. On modern computer controlled trucks idle is controlled completely by the PCM or engine computer; are you getting a check engine or service engine soon light?
The throttle body is a good, easy place to start, pull air intake tube off of the throttle body if the butterfly valve is open with key on, engine off you have a defect somewhere around the throttle body. Then the next place to look is throttle and cruise control cables and the valve return spring on the throttle body itself. The throttle body should be closed with no pressure on throttle pedal and cruise control off.
If the butterfly valve is closed, check the idle air control valve. If you are good at inspecting electronics use a digital multimeter with an ohm meter setting and check the ohm valve (most manufacters usually have a 40 to 80 ohm specification, if it's far outside those numbers you have a defective IAC valve).
If IAC valve or throttle body are not fault check for any vacuum leaks, if you don't have any vacuum leaks have the PCM inspected by an auto repair shop or the local chevy dealer repair shop.
The throttle body is a good, easy place to start, pull air intake tube off of the throttle body if the butterfly valve is open with key on, engine off you have a defect somewhere around the throttle body. Then the next place to look is throttle and cruise control cables and the valve return spring on the throttle body itself. The throttle body should be closed with no pressure on throttle pedal and cruise control off.
If the butterfly valve is closed, check the idle air control valve. If you are good at inspecting electronics use a digital multimeter with an ohm meter setting and check the ohm valve (most manufacters usually have a 40 to 80 ohm specification, if it's far outside those numbers you have a defective IAC valve).
If IAC valve or throttle body are not fault check for any vacuum leaks, if you don't have any vacuum leaks have the PCM inspected by an auto repair shop or the local chevy dealer repair shop.
Last edited by matthewp; 09-29-2012 at 07:58 PM.
#3
10-01-2012, 11:51 PM
Welcome to the forum, Dan.
First off...you asked a question and gave specifics as to what's happening. That's NOT a "stupid question".
Second...I am not a mechanic, but I have owned my Blazer for almost 15 years, and put nearly 200k miles on it. Mine was doing something similar...done it twice. Both times, it was the MAF (mass air flow) sensor. It would run fine for a few days, then do the same stuff you mentioned.
When you drive around...and you're going nice and smooth...does it ever feel like an invisible gremlin threw out an anchor for a second? Or like...your foot is on the gas, but it magically "lets up" even though you maintain steady pressure on the pedal?
Also...swing by the auto parts store and have them run a diagnostic (if you haven't already).
Last...you don't really own a Blazer...you're busted. *Unless we can see pics of her...
Again...welcome...this place is awesome!
First off...you asked a question and gave specifics as to what's happening. That's NOT a "stupid question".
Second...I am not a mechanic, but I have owned my Blazer for almost 15 years, and put nearly 200k miles on it. Mine was doing something similar...done it twice. Both times, it was the MAF (mass air flow) sensor. It would run fine for a few days, then do the same stuff you mentioned.
When you drive around...and you're going nice and smooth...does it ever feel like an invisible gremlin threw out an anchor for a second? Or like...your foot is on the gas, but it magically "lets up" even though you maintain steady pressure on the pedal?
Also...swing by the auto parts store and have them run a diagnostic (if you haven't already).
Last...you don't really own a Blazer...you're busted. *Unless we can see pics of her...
Again...welcome...this place is awesome!
#4
10-02-2012, 01:11 AM
First, as stated, I would unplug the MAF sesnor to see if it helps. If it does then clean it with MAF sensor spray only. Next I would check for any vaccum leaks around the throttle body/plenum. You can just use some brake cleaner to spray around them. If the idle changes, you have a vaccum leak where you sprayed.
#5
10-05-2012, 04:10 AM
Hey all,
Thank you for the replies on this topic. I will look into the MAF sensor this weekend.
Lunchbox, to answer your question, yes. It also is also struggles to keep it's idle and dies alot. Could that be MAF related?
Picture is up as requested. I will have a new one soon, once the fenders, hood & grille and doors are replaced.
Thank you for the replies on this topic. I will look into the MAF sensor this weekend.
Lunchbox, to answer your question, yes. It also is also struggles to keep it's idle and dies alot. Could that be MAF related?
Picture is up as requested. I will have a new one soon, once the fenders, hood & grille and doors are replaced.
#6
10-07-2012, 11:50 PM
Hey all,
Thank you for the replies on this topic. I will look into the MAF sensor this weekend.
Lunchbox, to answer your question, yes. It also is also struggles to keep it's idle and dies alot. Could that be MAF related?
Picture is up as requested. I will have a new one soon, once the fenders, hood & grille and doors are replaced.
Thank you for the replies on this topic. I will look into the MAF sensor this weekend.
Lunchbox, to answer your question, yes. It also is also struggles to keep it's idle and dies alot. Could that be MAF related?
Picture is up as requested. I will have a new one soon, once the fenders, hood & grille and doors are replaced.
#7
10-08-2012, 10:24 PM
Hi All,
I think the idle issue has been narrowed down. This weekend while checking a few things I noticed that there was 1. a vacuum leak, that has been fixed with a new hose installed. And 2. It is a MAF Sensor issue, I spent a lot of time on Dr.Google this weekend checking it out. It was suggested to disconnect the sensor and see if it runs better. Sure enough the idle started resting vs dropping and having the issue with the dying problem.
I did pick up some CRC MAF cleaner and cleaned the MAF out yesterday, giving it about 15 minutes in front of a fan to dry out. After re-assembling the unit and plugging in the electrical connection to the MAF the idle was rough and it was having issues running again.
I think it's going to require a replacement MAF, but I am not entirely sure. Thoughts please?
Also, on another tangent for a second, a friend suggested a high flow air filter by K&N. Are they worth the investment? or are they junk and should I stick with the WIX Filter?
Thanks!
Dan
I think the idle issue has been narrowed down. This weekend while checking a few things I noticed that there was 1. a vacuum leak, that has been fixed with a new hose installed. And 2. It is a MAF Sensor issue, I spent a lot of time on Dr.Google this weekend checking it out. It was suggested to disconnect the sensor and see if it runs better. Sure enough the idle started resting vs dropping and having the issue with the dying problem.
I did pick up some CRC MAF cleaner and cleaned the MAF out yesterday, giving it about 15 minutes in front of a fan to dry out. After re-assembling the unit and plugging in the electrical connection to the MAF the idle was rough and it was having issues running again.
I think it's going to require a replacement MAF, but I am not entirely sure. Thoughts please?
Also, on another tangent for a second, a friend suggested a high flow air filter by K&N. Are they worth the investment? or are they junk and should I stick with the WIX Filter?
Thanks!
Dan
#9
10-10-2012, 06:57 PM
Hi All,
I think the idle issue has been narrowed down. This weekend while checking a few things I noticed that there was 1. a vacuum leak, that has been fixed with a new hose installed. And 2. It is a MAF Sensor issue, I spent a lot of time on Dr.Google this weekend checking it out. It was suggested to disconnect the sensor and see if it runs better. Sure enough the idle started resting vs dropping and having the issue with the dying problem.
I did pick up some CRC MAF cleaner and cleaned the MAF out yesterday, giving it about 15 minutes in front of a fan to dry out. After re-assembling the unit and plugging in the electrical connection to the MAF the idle was rough and it was having issues running again.
I think it's going to require a replacement MAF, but I am not entirely sure. Thoughts please?
Also, on another tangent for a second, a friend suggested a high flow air filter by K&N. Are they worth the investment? or are they junk and should I stick with the WIX Filter?
Thanks!
Dan
I think the idle issue has been narrowed down. This weekend while checking a few things I noticed that there was 1. a vacuum leak, that has been fixed with a new hose installed. And 2. It is a MAF Sensor issue, I spent a lot of time on Dr.Google this weekend checking it out. It was suggested to disconnect the sensor and see if it runs better. Sure enough the idle started resting vs dropping and having the issue with the dying problem.
I did pick up some CRC MAF cleaner and cleaned the MAF out yesterday, giving it about 15 minutes in front of a fan to dry out. After re-assembling the unit and plugging in the electrical connection to the MAF the idle was rough and it was having issues running again.
I think it's going to require a replacement MAF, but I am not entirely sure. Thoughts please?
Also, on another tangent for a second, a friend suggested a high flow air filter by K&N. Are they worth the investment? or are they junk and should I stick with the WIX Filter?
Thanks!
Dan
#10
10-11-2012, 02:40 PM
To: 50lb_cat,
I wasn't under the assumption that would fix the issues I am having with my Blazer. I was just asking if they are a quality product and worth the investment?
To: 1sttimejimmyowner,
I'm still having some of the issues with the idle that you are. I'm not having the issue where it will die at a stop light any more. But, depending on if I have let it warm up a little bit before driving it will sit there and have a louder idle.
My next project for it is, a new maf sensor and to possibly clean the iac unit. Then a new fuel filter, spark plugs & wires, cap & rotor. I'm hoping that will help with the rough idle.
I bought the truck for $600 on Craigslist, it's got a lot of miles already under it's belt, I'm just trying to keep it running for a little while to stash some cash away for something (maybe still in the blazer family), newer or such, dunno.
Will update once I have done the MAF & IAC unit's.
-Dan
I wasn't under the assumption that would fix the issues I am having with my Blazer. I was just asking if they are a quality product and worth the investment?
To: 1sttimejimmyowner,
I'm still having some of the issues with the idle that you are. I'm not having the issue where it will die at a stop light any more. But, depending on if I have let it warm up a little bit before driving it will sit there and have a louder idle.
My next project for it is, a new maf sensor and to possibly clean the iac unit. Then a new fuel filter, spark plugs & wires, cap & rotor. I'm hoping that will help with the rough idle.
I bought the truck for $600 on Craigslist, it's got a lot of miles already under it's belt, I'm just trying to keep it running for a little while to stash some cash away for something (maybe still in the blazer family), newer or such, dunno.
Will update once I have done the MAF & IAC unit's.
-Dan