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Ok heres the story, several months ago my car developed a higher than normal idle and a noticeable miss when warmed up, at the time I didn't pay much mind to it as my drive to work was longer with very little stop and go so I blew it off.
Since i've moved back into the city my drive is shorter but with stop and go traffic it has become worse and the fuel consumption has gotten really bad, in the morning it's not noticeable at all (usually) but on my way home it's more prominant.
I'm thinking the differance in temp from early AM to late PM when the sun is out and the car gets hotter ???
In the last 2 weeks I have installed new plugs and wires which got rid of most of the miss, new PCV valve and found the Y union to be rotted behind the intake so I fixed that, removed the IAC valve and cleaned it, removed throttle body and cleaned it, cleaned the MAF (just sprayed not touched), air filter is clean and has not been touched in many months.
I have sprayed starting fluid, carb cleaner and brake clean along every nook and crevace of the intake, brake booster, air pump lines, vacuume lines, inlet piping to MAF, TB and related sensors, pretty much the entire engine and with the car running pushed and pulled on the intake TB, MAF, hoses ETC and I cannot find any leaks.
I have unplugged the MAF and IAC turned the ignition on for a few min to reset them and I still have the problem.
I am at my wit's end and getting more grey hair trying to figure out this problem, I know that higher Idle is more air coming in, but from where ??? I think I have exhausted all my options as to where to look and test.
The car is not flashing any SES, MIL etc codes and I have scanned for any pending codes and my scanner will not do real time, not that I know what to look for if it did.
can you guys point me in another direction of where / what to look for ??
Any and all help or Ideas would be greatly appreciated.
Thanks for your time
Bill
Since i've moved back into the city my drive is shorter but with stop and go traffic it has become worse and the fuel consumption has gotten really bad, in the morning it's not noticeable at all (usually) but on my way home it's more prominant.
I'm thinking the differance in temp from early AM to late PM when the sun is out and the car gets hotter ???
In the last 2 weeks I have installed new plugs and wires which got rid of most of the miss, new PCV valve and found the Y union to be rotted behind the intake so I fixed that, removed the IAC valve and cleaned it, removed throttle body and cleaned it, cleaned the MAF (just sprayed not touched), air filter is clean and has not been touched in many months.
I have sprayed starting fluid, carb cleaner and brake clean along every nook and crevace of the intake, brake booster, air pump lines, vacuume lines, inlet piping to MAF, TB and related sensors, pretty much the entire engine and with the car running pushed and pulled on the intake TB, MAF, hoses ETC and I cannot find any leaks.
I have unplugged the MAF and IAC turned the ignition on for a few min to reset them and I still have the problem.
I am at my wit's end and getting more grey hair trying to figure out this problem, I know that higher Idle is more air coming in, but from where ??? I think I have exhausted all my options as to where to look and test.
The car is not flashing any SES, MIL etc codes and I have scanned for any pending codes and my scanner will not do real time, not that I know what to look for if it did.
can you guys point me in another direction of where / what to look for ??
Any and all help or Ideas would be greatly appreciated.
Thanks for your time
Bill
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even though you cleaned the MAF it could be shot still, as far as the idling problem I'd start there personally. My 95 Z28 did that (yes I know you have the LS but I'm trying to relate) so I had it replaced and the problem went away even though my car wasn't throwing any codes like yours isn't. IMO replace the MAF with a new one and go from there.
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It would really be beneficial to look at live data to help rule a few things out like MAF, possible IAC, etc. Other possibilities could be vacuum leak(internal or external), but a vac. leak should throw lean codes P0171/p0174. Do you hear any type of hissing in or around the intake?
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Thanks for the replies everyone, I'm looking in the classifieds for a MAF and IAC (no luck yet) if I have to try one i would rather it be a cheap used one than a new one.
I hate throwing parts at a problem in the hopes of fixing it, especially since I cant get that $$ tree to grow in the back yard lol.
I also read somewhere here about the MAF and unplugging it, I have done that the idle dropped about 50 rpm then went right back to what seems to be 975 ish.
could it be the problem even tho unplugging it made almost no diff ??
any Ideas where to get live data as the car is running that wont cost an arm and leg ??
Thanks again guys, I really appreciate the Ideas.
I hate throwing parts at a problem in the hopes of fixing it, especially since I cant get that $$ tree to grow in the back yard lol.
I also read somewhere here about the MAF and unplugging it, I have done that the idle dropped about 50 rpm then went right back to what seems to be 975 ish.
could it be the problem even tho unplugging it made almost no diff ??
any Ideas where to get live data as the car is running that wont cost an arm and leg ??
Thanks again guys, I really appreciate the Ideas.
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Another thing to check is your o2's. I have had plenty going out or on there way, abd I never got any code. When your o2's start to fail you get a real bad idle. Also if they were all the way gone, you would have bad surging abd horrible ride intill 3-4krpm. Also I would get a volt Metter on your tps. You need to start over, and work you way from front to back of car ruling everything out. It could be a clogged filter or pump on it's last leg. Also double check your coil harness is plugged in and getting power.I've had to put some elec grease on mine due to #7 cutting in and out.
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Another thing to check is your o2's. I have had plenty going out or on there way, abd I never got any code. When your o2's start to fail you get a real bad idle. Also if they were all the way gone, you would have bad surging abd horrible ride intill 3-4krpm. Also I would get a volt Metter on your tps. You need to start over, and work you way from front to back of car ruling everything out. It could be a clogged filter or pump on it's last leg. Also double check your coil harness is plugged in and getting power.I've had to put some elec grease on mine due to #7 cutting in and out.
I will try a search for the TPS voltages and steps on how to check it.
harness is connected and powering and the dialectic grease is a good preventative I will do.
filter should be good since I changed it in the last 7 months and the car still does it, fuel pump will suck unless I cut a hole behind the back seats, I'll see if I can borrow a fuel pressure test kit before I start hacking the car up lol.
I should have brought that damn predator scanner when I had the chance then I could have live data, oh well....live and learn.
Thanks very much for the ideas and suggestions guys.
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Well.....I think I have a leaking head gasket ![Nono](https://ls1tech.com/forums/images/smilies2/nono.gif)
I did a coolant pressure test and it fails miserably, I pump it to 15 psi and it instantly bleeds down to a steady 4 psi.![Bang Head](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_banghead.gif)
&^^%#$%$@^&& POS
I checked under for leaks and none, nothing in the oil, I tried to see if I could hear a hissing in the oil filler cap and nothing.
no hissing at the pump cap either so I know it has a good seal.
anyone know of any sales on headgaskets and bolts ??
![Nono](https://ls1tech.com/forums/images/smilies2/nono.gif)
I did a coolant pressure test and it fails miserably, I pump it to 15 psi and it instantly bleeds down to a steady 4 psi.
![Bang Head](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_banghead.gif)
&^^%#$%$@^&& POS
I checked under for leaks and none, nothing in the oil, I tried to see if I could hear a hissing in the oil filler cap and nothing.
no hissing at the pump cap either so I know it has a good seal.
anyone know of any sales on headgaskets and bolts ??
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Make sure it's not leaking coolant at the water pump. They all seem to leak a little there.
Also I have a spare maf, I do not think I want to sell it but I work in Gainesville at the autozone on univeristy. If you want I will bring it to work with me today. I work 12-9.
I hope it's not a headgasket. Good luck.
Steven
Also I have a spare maf, I do not think I want to sell it but I work in Gainesville at the autozone on univeristy. If you want I will bring it to work with me today. I work 12-9.
I hope it's not a headgasket. Good luck.
Steven
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Make sure it's not leaking coolant at the water pump. They all seem to leak a little there.
Also I have a spare maf, I do not think I want to sell it but I work in Gainesville at the autozone on univeristy. If you want I will bring it to work with me today. I work 12-9.
I hope it's not a headgasket. Good luck.
Steven
Also I have a spare maf, I do not think I want to sell it but I work in Gainesville at the autozone on univeristy. If you want I will bring it to work with me today. I work 12-9.
I hope it's not a headgasket. Good luck.
Steven
crazy damn thing will only leak with the nose pointed down the slope of my driveway, I pulled it in the garage yesterday after work and let it run for 25 min and no leaks, got frustrated and said screw it then parked it.
This morning same thing, leaks when pointed down the slope and now theres a little squeal from under the hood so........I will make sure Saturday morning when it's light out that it is the pump and I'll go from there.
And on another note, man thats a real nice thing to offer your MAF for me to try, I really appreciate it very much.
Things like that remind me that there still are some good people out there.
Thanks again to everyone who has replied with your Ideas and suggestions, I will update when I find more info.
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Yea my pump only leaks, sometimes too. Has to be the right circumstances. I hope it all turns out to be the water pump gasket or the pump at worse. Let me know if you need to try the maf. I work the next 5 days straight.
Steven
Steven
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Well I picked up a new water pump Sat morning, got it all installed and no more leaks. (so far)
I could have gotten away with just replacing the gaskets since the rubber bits were really brittle and split away from the gasket frame but figured WTF I already purchased it and the old one is off.
A new WP is good preventative Maintenance anyways.
I haven't pressure tested it again yet, but i'm planning on it when I get off work tomorrow and it cools off.
Yes, a compression test would let me know if I have a problem in a cylinder with rings, valves, HG.
I've been wanting to do one anyways, I will see if my friend at work has one I can borrow.
It still has a little bit of a rough idle......I'll figure that out eventually![Bang Head](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_banghead.gif)
![Bang Head](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_banghead.gif)
Thanks to everyone for their offers, suggestions, tips and ideas, I greatly appreciate it and will update how things go in the next few days etc.
I could have gotten away with just replacing the gaskets since the rubber bits were really brittle and split away from the gasket frame but figured WTF I already purchased it and the old one is off.
A new WP is good preventative Maintenance anyways.
I haven't pressure tested it again yet, but i'm planning on it when I get off work tomorrow and it cools off.
Yes, a compression test would let me know if I have a problem in a cylinder with rings, valves, HG.
I've been wanting to do one anyways, I will see if my friend at work has one I can borrow.
It still has a little bit of a rough idle......I'll figure that out eventually
![Bang Head](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_banghead.gif)
![Bang Head](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_banghead.gif)
Thanks to everyone for their offers, suggestions, tips and ideas, I greatly appreciate it and will update how things go in the next few days etc.