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Old 07-17-2014, 07:17 PM   #1
robotnix
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Default here is how I fixed my idle problem

hi,

so my idle problem happened only after driving the car hot and at idle so stopped in my own parking or stop or red light.

the rpm would go to 1000, down to 650, up to 800 down to 500, up to 500 down to 300 and die. I was able to restart the car right away. if I would press the pedal and rev it to 3000-4000 rpm the issue would go away but we all agree that we look like idiots revving at a red light but the problem would come back at next light.

now I got to fix it but it took me I would say about 2 months of trial. I did change quiet few things but only because I wanted to it's all basic maintenance on a 22 years old 5.0 so I was ok with it since I plan on keeping the car for years.

I did all these things but none helped,
- change cap, rotor, spark plugs, spark plug wires.
- clean MAF sensor,
- clean IAC
- change EGR
- change PCV valve
- change alternator for a newer 130AMP G3
- temperature sensor for the computer and while at it temperature sensor for the dash

I did these 3 same day so the problem is I can't say for sure which one helped but at least it will give you an idea and as I said it's basic maintenance and they're cheap.
- I had a O2 sensor light on for driver side o2, I changed both sides I was running too rich
- I changed my TPS for the BBK version.
- I changed the IAC

since then so far in 2 days not once I've had bad idle being parked, stop or red light and my idle is steady at 650 RPM. I never had to play with the TB screw.

if I had to take a wild guess I would say the IAC fixed it. I didn't change it at the beginning because 2 months earlier it's the first thing I cleaned with carb cleaner but I guess it didn't help.

again this is what I did and it helped me. it's not a fix for your car, I'm just posting this to explain what I did to fix my own car.

thanks.
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Last edited by robotnix; 07-17-2014 at 07:42 PM.
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Old 07-18-2014, 12:06 AM   #2
mjr46
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lol...replaced every sensor nearly.....slap parts until it solves prob and if not...slap even more
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Old 07-18-2014, 06:08 AM   #3
robotnix
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lol...replaced every sensor nearly.....slap parts until it solves prob and if not...slap even more
You can put it that way but as i explained i was going to do all this anyway simply as preventive changes on a 22 years old car and most things are cheap so i see no reason not too.

But again it could have been a combination of these things that fixed it for me... It s just out there take it or leave it.

if i put all the bills together except the alternator i m at about 350$ or so for new parts. Paying a mechanic to try to diagnose would have cost me more for less.

Thanks..

Last edited by robotnix; 07-18-2014 at 06:21 AM.
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Old 07-18-2014, 02:43 PM   #4
88 orangepeel notch
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Thanks for the update, glad to hear she's idling like it should. Congrats
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Old 07-18-2014, 07:23 PM   #5
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Quote:
Originally Posted by robotnix View Post
You can put it that way but as i explained i was going to do all this anyway simply as preventive changes on a 22 years old car and most things are cheap so i see no reason not too.

But again it could have been a combination of these things that fixed it for me... It s just out there take it or leave it.

if i put all the bills together except the alternator i m at about 350$ or so for new parts. Paying a mechanic to try to diagnose would have cost me more for less.

Thanks..
I had a shop (ALL OUT AUTOMOTIVE)These bums tried and charge me a grand for an electrical gremlin. All they managed to do after having my car for 3 months is make the problem worse. If you fixed the problem on your own consider it money well spent. And you got to learn your car in the process. Trust me a speed shop would use the same throw parts at it approach. And charge you 120 bucks an hour for labor while they are scratching their heads and asses trying to figure out the problem.!
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2011 CamaroSS 12.34@110.92

Last edited by bluebeastsrt; 07-18-2014 at 07:27 PM.
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Old 07-18-2014, 11:05 PM   #6
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Quote:
Originally Posted by bluebeastsrt View Post
I had a shop (ALL OUT AUTOMOTIVE)These bums tried and charge me a grand for an electrical gremlin. All they managed to do after having my car for 3 months is make the problem worse. If you fixed the problem on your own consider it money well spent. And you got to learn your car in the process. Trust me a speed shop would use the same throw parts at it approach. And charge you 120 bucks an hour for labor while they are scratching their heads and asses trying to figure out the problem.!
sounds like you need to find a technician, and not a parts slapper....you know there are plenty of techs out there who can and do troubleshoot properly, just happens most don't work at dealers and hole in the wall shops..............what I find often is the criteria people use when searching for a shop is they call around and ask what the labor rate is and when they find the cheapest rate.....guess what?? bingo...that's who they go with. Cheap labor rates often go hand in hand with a shops expertise and investment they have in equipment that allows for proper diagnosis.........most don't even have lab scopes or techs that even know how to use them. I have a few jaw dropping case scenarios in the last month that I encountered. Glad the OP got his problem fixed........more power to him
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Old 07-19-2014, 01:49 AM   #7
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Quote:
Originally Posted by mjr46 View Post
sounds like you need to find a technician, and not a parts slapper....you know there are plenty of techs out there who can and do troubleshoot properly, just happens most don't work at dealers and hole in the wall shops..............what I find often is the criteria people use when searching for a shop is they call around and ask what the labor rate is and when they find the cheapest rate.....guess what?? bingo...that's who they go with. Cheap labor rates often go hand in hand with a shops expertise and investment they have in equipment that allows for proper diagnosis.........most don't even have lab scopes or techs that even know how to use them. I have a few jaw dropping case scenarios in the last month that I encountered. Glad the OP got his problem fixed........more power to him
I make about 150K a year. So the cheapest rate thing doesn't apply to me. I took my car to this speed shop thinking their shop car is an 8.5 second car and that you'd think they know what they are doing? Makes sense right? I'm building a race car and they own & supposedly build race cars. Not the case. Finding a good mechanic/Tech is the same as finding a good cop or fast food worker. They are out there for sure and I would never lump all techs into the same group but if you do happen to find one you can trust. Keep him! Because your just as likely to find some Billy Bob HACK as you are a competent mechanic. Your just rolling the dice when you take your car to a shop for the first time. I've also found your better off just fixing it yourself about 75% of the time. You should know your limits when trying to fix something yourself though. My limits are usually electrical related. Don't take offense to any of my above statements. I'm sure you do fine work. But its a crap shoot finding a good one.
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2011 CamaroSS 12.34@110.92

Last edited by bluebeastsrt; 07-19-2014 at 03:25 AM. Reason: grammar.
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Old 07-21-2014, 04:35 AM   #8
Maxwelhse
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Robotnix, the next time I see a thread about what $10k engine package you want to buy someday, I'm literally going to tell you to buy some training instead. That's not meant to be hurtful or insulting, but no one can teach you if you flat don't know and don't ask for help. Or... You can toss money at it until it goes away.

I LOVE the fact that new and younger guys are coming into push rod 5.0's, but cool your jets. As MJR said, you bought most of the motor to fix that...

I've made some good income in my life too, but I try not to be stupid about what I do with it despite what some pundits may think of my choices.

Chill out and learn to work on your car. Your life will be MUCH better. You could have bought a proper data logging scan tool for less than those parts if you wanted to. I, or hopefully some other people here, could interpret those logs and help you to change *1* part.

Point made? No hard feelings?
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Last edited by Maxwelhse; 07-21-2014 at 04:44 AM.
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Old 07-21-2014, 07:51 AM   #9
robotnix
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Quote:
Originally Posted by Maxwelhse View Post
Robotnix, the next time I see a thread about what $10k engine package you want to buy someday, I'm literally going to tell you to buy some training instead. That's not meant to be hurtful or insulting, but no one can teach you if you flat don't know and don't ask for help. Or... You can toss money at it until it goes away.

I LOVE the fact that new and younger guys are coming into push rod 5.0's, but cool your jets. As MJR said, you bought most of the motor to fix that...

I've made some good income in my life too, but I try not to be stupid about what I do with it despite what some pundits may think of my choices.

Chill out and learn to work on your car. Your life will be MUCH better. You could have bought a proper data logging scan tool for less than those parts if you wanted to. I, or hopefully some other people here, could interpret those logs and help you to change *1* part.

Point made? No hard feelings?
I will only say that I'm glad I was able to fix my problem myself with just 350$ and few new parts, I could have been robbed by some mechanic and still end up having the same issue.

most of things I did on my car are things the community suggested and I did it because they made sense and I accepted.

I always say in my posts that I'm no mechanic, yet with the help from bluebeastsrt and some others here I was able to change from radiator up to my own timing chain and even install an electric fan which allowed me to learn about my car so thanks for the support. youtube and forums is all the training I need I'm not going to change job to get a mechanic training but thanks for the suggestion.

no friend no hard feelings.

Last edited by robotnix; 07-21-2014 at 08:43 AM.
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Old 07-21-2014, 03:05 PM   #10
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Thumbs up idle problem

I'm having almost the same exact problem and on my 26 year old, so I will find this article very useful. I will try the bottom three things first, but like you I see no reason not replacing everything you mention for the sake of it being such and old car.


Quote:
Originally Posted by robotnix View Post
hi,

so my idle problem happened only after driving the car hot and at idle so stopped in my own parking or stop or red light.

the rpm would go to 1000, down to 650, up to 800 down to 500, up to 500 down to 300 and die. I was able to restart the car right away. if I would press the pedal and rev it to 3000-4000 rpm the issue would go away but we all agree that we look like idiots revving at a red light but the problem would come back at next light.

now I got to fix it but it took me I would say about 2 months of trial. I did change quiet few things but only because I wanted to it's all basic maintenance on a 22 years old 5.0 so I was ok with it since I plan on keeping the car for years.

I did all these things but none helped,
- change cap, rotor, spark plugs, spark plug wires.
- clean MAF sensor,
- clean IAC
- change EGR
- change PCV valve
- change alternator for a newer 130AMP G3
- temperature sensor for the computer and while at it temperature sensor for the dash

I did these 3 same day so the problem is I can't say for sure which one helped but at least it will give you an idea and as I said it's basic maintenance and they're cheap.
- I had a O2 sensor light on for driver side o2, I changed both sides I was running too rich
- I changed my TPS for the BBK version.
- I changed the IAC

since then so far in 2 days not once I've had bad idle being parked, stop or red light and my idle is steady at 650 RPM. I never had to play with the TB screw.

if I had to take a wild guess I would say the IAC fixed it. I didn't change it at the beginning because 2 months earlier it's the first thing I cleaned with carb cleaner but I guess it didn't help.

again this is what I did and it helped me. it's not a fix for your car, I'm just posting this to explain what I did to fix my own car.

thanks.
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Old 07-21-2014, 03:05 PM
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