VIBRATIONS, HIGH IDLE, ROUGH 3rd->2nd DOWNSHIFT & ZAP

[clone2020]

1999 Mitsu Galant ES (all stock)
-------------------------------------
-At startup in park/neutral, it idles at 1500rpms
-At idle in drive w/brake pressed, my steering wheel vibrates...
-when moving, it's smoooth like butter...

-When I'm driving at the 25mph mark and let go of the gas, it kinda jerks. Not bad but I can feel it. A definate downshift. High/Mid pitch tone (3rd) then shifts to (2nd) low rumble tone.

-Also, When I step out of my car and touch the metal frame, I get ZAPPED!!! BIG TIME!!! Bad ground cable? Tires?

http://www.clubtgc.org/forum/viewtopic.php?t=6304 ('http://www.clubtgc.org/forum/viewtopic.php?t=6304')
To screw or not to screw?

I've cleaned my throttle body and my entire plastic intake, replaced air filter, flushed transmission w/mitsu ATF, replaced tranny filter, coolant, oil, changed spark plugs, PCV valve, & new battery.

Any ideas?

-Mike.

[Fishboy55]

You might want to try resetting your PCM just for the heck of it. As stated in so many posts, don't mess with the idle adjustment screw. To reset the PCM, remove your negative battery cable for 15-20 minutes, then replace it. Make sure you have the security code for your radio handy, because you'll likely need to re-enter that.

Chip

[FinalLast]

<div class='quotetop'>QUOTE(clone2020)</div><div class='quotemain'>1999 Mitsu Galant ES (all stock)
-------------------------------------
-At idle in drive, my steering wheel vibrates
-At idle in park/neutral, it's fine...
-when moving, it's smoooth like butter...
-It varies in idle speed: 750-1100rpms

-When I'm driving at the 25mph mark and let go of the gas, it kinda jerks. Not bad but I can feel it. A definate downshift. High/Mid pitch tone (3rd) then shifts to (2nd) low rumble tone.

http://www.clubtgc.org/forum/viewtopic.php?t=6304 ('http://www.clubtgc.org/forum/viewtopic.php?t=6304')
To screw or not to screw?

I've cleaned my throttle body and my entire plastic intake, replaced air filter, flushed transmission w/mitsu ATF, replaced tranny filter, coolant, oil, changed spark plugs, PCV valve, & new battery.

Any ideas?</div>


I have the exact same problem.
Wonder whats going on.
BTW I've also done:
-clean TB
-air filter
-tranny service
-plugs

[Gilhuly]

This could be a cold weather/ bad thermostat issue. Does your temp needle ride below center? Your car might not be getting out of cold engine mode. Is your gas mileage crappy? You shouldn't be idling much over 800. Did you do the throttle body cable mod? May be too tight

[clone2020]

<div class='quotetop'>QUOTE(Gilhuly)</div><div class='quotemain'>This could be a cold weather/ bad thermostat issue. Â*Does your temp needle ride below center? Â*Your car might not be getting out of cold engine mode. Â*Is your gas mileage crappy? Â*You shouldn't be idling much over 800. Â*Did you do the throttle body cable mod? Â*May be too tight</div>

YEAH!!! It DOES ride below the center mark!!! AND my gas mileage is CRAPPY!!!

I did not modify the TB cable.

Great idea!!! I'll replace the thermostat.

Should the temp needle be exactly at the middle/center mark?

[clone2020]

<div class='quotetop'>QUOTE(Fishboy55)</div><div class='quotemain'>You might want to try resetting your PCM just for the heck of it. As stated in so many posts, don't mess with the idle adjustment screw. To reset the PCM, remove your negative battery cable for 15-20 minutes, then replace it. Make sure you have the security code for your radio handy, because you'll likely need to re-enter that.

Chip</div>

The battery already got reset when I purchased a new battery. It took about 20-30 starts for it to relearn everything.

[Fishboy55]

<div class='quotetop'>QUOTE(Gilhuly)</div><div class='quotemain'>This could be a cold weather/ bad thermostat issue. Â*Does your temp needle ride below center? Â*Your car might not be getting out of cold engine mode. Â*Is your gas mileage crappy? Â*You shouldn't be idling much over 800. Â*Did you do the throttle body cable mod? Â*May be too tight</div>
I did the TB coolant bypass. I wonder if that's why my gas mileage is crappy too. Guess I'll switch it back this weekend. Thanks!!

Chip

[clone2020]

<div class='quotetop'>QUOTE(Fishboy55)</div><div class='quotemain'><div class='quotetop'>QUOTE(Gilhuly)</div><div class='quotemain'>This could be a cold weather/ bad thermostat issue. Â*Does your temp needle ride below center? Â*Your car might not be getting out of cold engine mode. Â*Is your gas mileage crappy? Â*You shouldn't be idling much over 800. Â*Did you do the throttle body cable mod? Â*May be too tight</div>
I did the TB coolant bypass. I wonder if that's why my gas mileage is crappy too. Guess I'll switch it back this weekend. Thanks!!

Chip</div>

What's the TB coolant bypass?

[clone2020]

Also, my front rotors made horrid sqeeking noises. I guess this is common with mitsu stock rotors? I replaced the pads with no change. I haven't had time to replace the rotors with new cross-drilled brembos so I just took some fine grit sandpaper and lightly sanded them. So far, no more sqeeking.

-Mike.

[Fishboy55]

There's a coolant line that runs through your Throttle Body to keep it from freezing in the winter. The bypass just takes that line off and routes the coolant straight back to the block. It will keep your TB cooler which means the airt going in is more dense, but that may be why my gas mileage went to shit after it got colder outside. Maybe my car is running in cold engine mode all the time. It's easy to back it off, just a couple hose clamps, so I'll do that tomorrow.

Chip

[manybrews]

<div class='quotetop'>QUOTE(Fishboy55)</div><div class='quotemain'>There's a coolant line that runs through your Throttle Body to keep it from freezing in the winter. The bypass just takes that line off and routes the coolant straight back to the block. It will keep your TB cooler which means the airt going in is more dense, but that may be why my gas mileage went to shit after it got colder outside. Maybe my car is running in cold engine mode all the time. It's easy to back it off, just a couple hose clamps, so I'll do that tomorrow.

Chip</div>
actually, it has nothing to do with that. its there for cold idle speed up, and thats it.

[clone2020]

<div class='quotetop'>QUOTE(manybrews)</div><div class='quotemain'><div class='quotetop'>QUOTE(Fishboy55)</div><div class='quotemain'>There's a coolant line that runs through your Throttle Body to keep it from freezing in the winter. The bypass just takes that line off and routes the coolant straight back to the block. It will keep your TB cooler which means the airt going in is more dense, but that may be why my gas mileage went to shit after it got colder outside. Maybe my car is running in cold engine mode all the time. It's easy to back it off, just a couple hose clamps, so I'll do that tomorrow.

Chip</div>
actually, it has nothing to do with that. its there for cold idle speed up, and thats it.</div>

Hey Manybrews,

So, what should I do about my high idle, vibration, & downshift problems? Someone recommended replacing the thermostat. Do you think it's a good idea?

-Mike.

[JiP]

And a cold throttle body would not make your intake air colder. The air passign through the tb passes too fast for it to be cooled by a cold tb. So basically your doing nothing performance wise at all.

[Fishboy55]

<div class='quotetop'>QUOTE(JiP)</div><div class='quotemain'>And a cold throttle body would not make your intake air colder. Â*The air passign through the tb passes too fast for it to be cooled by a cold tb. Â*So basically your doing nothing performance wise at all.</div>
So if that's true, then removing the coolant hose from the TB to keep it cooler in the first place is a waste of time. Am I understanding that correctly?

Chip

[clone2020]

I changed the thermostat today. No change. Do I have to start taking apart the engine now?

SYMPTOMS
-------------
-rough idle (750-1000)
-vibrations in the steering wheel
-rough 3rd->2nd downshift
-static electricity buildup when driving (When I turn off the engine, step out of the car and touch the door I get ZAPPED!)

...any more ideas?

-Mike.

[Auto-9]

From what I can gather...you have all the symptons of my car when it was stock so it might just be that way from the factory. The zapping is normal...the Galant is really nasty about that unless you have leather seats.

[JiP]

<div class='quotetop'>QUOTE</div><div class='quotemain'>So if that's true, then removing the coolant hose from the TB to keep it cooler in the first place is a waste of time. Am I understanding that correctly? Â*
</div>

Yes. Its pretty much basic highschool physics. Unless your cooling your TB to like -20 degrees, your not going to be chaning the air temp passing through. Same arguement some poeple have with plastic or metal intake pipes, some people will say well metal conducts heat and will make your air hot. No it wont, the air flows through it too fast to be affected. You want cold air, put your filter pointing out of the front of your bumper so its in the air strea, hence the name Cold Air Intake. https://www.thegalantcenter.org/style_emoticons/default/laugh.gif https://www.thegalantcenter.org/style_emoticons/default/biggrin.gif

[clone2020]

<div class='quotetop'>QUOTE(Rallifan)</div><div class='quotemain'>From what I can gather...you have all the symptons of my car when it was stock so it might just be that way from the factory. The zapping is normal...the Galant is really nasty about that unless you have leather seats.</div>

So, what did you modify to get the idle, vibrations , & 3rd->2nd downshift back to normal?

-Mike.

[Gilhuly]

Have you owned the car since new? That idle speed is just too high. I'd loosen the Throttle body cable just to see if you are truly running at idle.

[clone2020]

<div class='quotetop'>QUOTE(Gilhuly)</div><div class='quotemain'>Have you owned the car since new? Â*That idle speed is just too high. Â*I'd loosen Â*the Throttle body cable just to see if you are truly running at idle.</div>

I am the second owner. How do I know if the TB has been messed with?

-Mike.

[clone2020]

When I start my car, the idle stays at 1500rpms until about 10-15 minutes then it slowly goes down to 1000rpms. After about 15-20 minutes of driving, it idles at 750.

Is this normal?

-Mike.

[manybrews]

no. it should idle at about 1200 to 1400 for the first few minutes, max.

it should then settle into a 750 rpm idle after slowly decreasing to it.

[clone2020]

<div class='quotetop'>QUOTE(manybrews)</div><div class='quotemain'>no. Â*it should idle at about 1200 to 1400 for the first few minutes, max.

it should then settle into a 750 rpm idle after slowly decreasing to it.</div>

Should I adjust the idle screw? or the Throttle Body cable?

-Mike.

[Gilhuly]

Throttle body cable, but I will certainly defer to Manybrews if he chimes in. Do you know where that 2 screw bracket is on the back side of the engine compartment? The thing is this car has a very sophisticated computer for better or worse and it wants to do what Manybrews said unless its being physically forced not to. Do not touch the idle screw.

[clone2020]

I just added an AEM CAI and tightened the trottle cable.

The vibrations are much less and it idles at 750rpms...

But now my Climate Control Fan doesn't work. DOH!!!

-Mike.

[Fishboy55]

<div class='quotetop'>QUOTE(clone2020)</div><div class='quotemain'>For those of you who have a cold air intake, do any of you have an AEM bypass valve? ...to prevent hydrolock?

-Mike.</div>
Yea Mike, I have one I picked up off ebay for $20. They're different sized depending on the outside diameter of your intake pipe. My CP Racing CAI is 2.75 inches. Fits like a champ.

Chip

[vyrt1go]

actually...the 8g Galants DO have a very sophisticated computer in them (considering the price range of the galants...) and here is the reasons for the idle differences....

1. Altitude/O2 content in the air (Colorado at 8000 ft. and dry will be different than Death Valley @ sea level and humid)...
2. If you read in the Owners manual it says that when you start the car, it will idle higher (1400 - 1500 r's is normal) right off the bat and gradually slow down...and this is why...with Cast Iron blocks and Aluminum heads, the rates at which each heat and cool is dramatically different. the engineers know this and the computer is programmed to idle the car at what it feels is the right RPM's to warm the engine up at a rate that allows these two metals (and the gaskets between them) to expand at a uniform rate to reduce premature gasket failure/block stress/head stress...during this time the computer is going through its routin to get everything else in order...O2 sensors, exhaust sensors, air/fuel sensors...etc.

it is the best practice to start your car and let it run (withoug stepping on the gas) until the temp needle starts to move. once the needle gets to the bottom of the first hash, the car has done what it needs to do...after that, you are just wasting fuel...

...that said, it is never a good idea to start the car after 8 hours in 30 degree weather, drop it in drive and go blasting across town...it usually takes the duration of 1 good tune on the CD player to warm the car up...

...also, the galants learn your driving habits and adapt the tranny accordingly, and if you were the driving nazi all last week, then want to just go easy on it and chill, you might get what seem like hard up-shifts/down shifts because the car trained itself that you liked quicker/harder shifts....drive like a granny for a week, and it will adapt...

later

~v