Moparts Main Index | READ - Info & Help Page | Moparts Sponsors | Tech Archive

Forums Calendar Active Threads Search Forum Help
Previous Thread
Next Thread
Print Thread
Page 3 of 3 1 2 3
Re: The famous Neon rough idle question... [Re: Grizzly] #1632689
06/17/14 10:56 AM 06/17/14 10:56 AM
Joined: Jan 2003
Posts: 11,993
Benton, IL.
D
DaveRS23 Offline
Special needs idiot
DaveRS23  Offline
Special needs idiot
D

Joined: Jan 2003
Posts: 11,993
Benton, IL.
Quote:

Quote:

...........I'll have to check my coil pack too, and I still have to check the resistance on my injectors.



I had 12.4 to 12.7 Ohm all the way across on mine.

Injector Testing

Also, in that troubleshooting series I used their method for testing the coil:

Coil Test

Had a nice, fat spark.

I pulled all the plugs last night and tightened the gap to .30: run it again for awhile and see what happens.

Good luck.

I'm still thinking about drilling the hole in the throttle plate....



Something to think about; The computer is always trying to hit the programmed idle speed and uses both air flow and timing to get there. If you drill the plate allowing more air in and the computer can't control the idle with the IAC, it will do it with timing. So it could pull too much timing out at idle.

Less timing at idle may not be a good thing.

Master, again and still
Re: The famous Neon rough idle question... [Re: DaveRS23] #1632690
06/17/14 11:31 AM 06/17/14 11:31 AM
Joined: Sep 2007
Posts: 14,889
up yours
Supercuda Offline
About to go away
Supercuda  Offline
About to go away

Joined: Sep 2007
Posts: 14,889
up yours
My question is, did you reset the computer after you fixed the vacuum leak?

They say there are no such thing as a stupid question.
They say there is always the exception that proves the rule.
Don't be the exception.
Re: The famous Neon rough idle question... [Re: Supercuda] #1632691
06/17/14 02:02 PM 06/17/14 02:02 PM
Joined: May 2006
Posts: 1,414
Stow ,Ohio
D
demon440 Offline
pro stock
demon440  Offline
pro stock
D

Joined: May 2006
Posts: 1,414
Stow ,Ohio
I have an 04 Neon with 95,000. miles
I am the original owner. This car had a rough idle since day 1. Dealer told me it's normal.
Recently it has a bad stumble, almost like it cuts out. In the past I have put 2 MSD coils on it and changed plugs and wires. Recently replaced
the solenoid on the fire wall for emissions but that didn't help.
Re: The famous Neon rough idle question... [Re: demon440] #1632692
06/21/14 05:22 AM 06/21/14 05:22 AM
Joined: Mar 2005
Posts: 1,630
North Central Florida
E
eightlitermopar Offline OP
top fuel
eightlitermopar  Offline OP
top fuel
E

Joined: Mar 2005
Posts: 1,630
North Central Florida
Quick update. I have done nothing but drive the car

Seriously though, I didn't know if the car was relearning or not after being in the shop. I put some Lucas injector cleaner in and have been driving it.

Idle still hovers about 600-800 RPM, starts right up and drives fine.

I guess I can't complain though. I have seen some 4 cylinder cars shake so bad at idle you would think it had an uneven washing machine running under the hood.

I do want to do a compression test though just for kicks. I will post the results as soon as I get them.

eightlitermopar

Mopar or no car
Re: The famous Neon rough idle question... [Re: That AMC Guy] #1632693
06/22/14 12:19 AM 06/22/14 12:19 AM
Joined: Mar 2003
Posts: 710
Harrisburg Pa. 17112
M
moparmikethree Offline
super stock
moparmikethree  Offline
super stock
M

Joined: Mar 2003
Posts: 710
Harrisburg Pa. 17112
Have the timing belt rechecked. It is off a tooth on the can sprockets
Re: The famous Neon rough idle question... [Re: demon440] #1632694
06/22/14 12:26 AM 06/22/14 12:26 AM
Joined: Aug 2011
Posts: 1,083
SE PA
Yellow Fever Offline
super stock
Yellow Fever  Offline
super stock

Joined: Aug 2011
Posts: 1,083
SE PA
Quote:

I have an 04 Neon with 95,000. miles
I am the original owner. This car had a rough idle since day 1. Dealer told me it's normal.
Recently it has a bad stumble, almost like it cuts out. In the past I have put 2 MSD coils on it and changed plugs and wires. Recently replaced
the solenoid on the fire wall for emissions but that didn't help.



Do the timing belt, water pump and tensioner if you haven't yet! It will bend valves if it breaks!!
Re: The famous Neon rough idle question... [Re: moparmikethree] #1632695
06/22/14 01:45 PM 06/22/14 01:45 PM
Joined: Mar 2005
Posts: 1,630
North Central Florida
E
eightlitermopar Offline OP
top fuel
eightlitermopar  Offline OP
top fuel
E

Joined: Mar 2005
Posts: 1,630
North Central Florida
Quote:

Have the timing belt rechecked. It is off a tooth on the can sprockets



I thought of this, but I understand that if it is off 1 tooth it will throw a code

Mopar or no car
Re: The famous Neon rough idle question... [Re: eightlitermopar] #1632696
06/22/14 02:35 PM 06/22/14 02:35 PM
Joined: Jan 2006
Posts: 8,162
USA
3
360view Offline
Moparts resident spammer
360view  Offline
Moparts resident spammer
3

Joined: Jan 2006
Posts: 8,162
USA
You might try directing some propane from an unlit torch into the intake to the air filter after the engine is fully warmed up.
(when started cold the air fuel ratio is very rich anyway)

If one or more of your fuel injector tips have deposit build ups interfering with the short solenoid plunger up down at idle, the extra propane should smooth out the idle.

If the IAC is working correctly it should adjust while this is happening and RPM should keep returning to spec as the propane is quickly added or taken away.

While you have the propane torch out check for air leaking past gaskets or o- rings.r

Carbon deposits on the backsides of intake valves can also cause a rough idle.

If you are going to keep driving it
add a bottle of Chevron Techron Plus to your next tank,
a bottle of Gumout Regane to the 2nd tank,
then a bottle of Redline SI-1 to the third tank.

This is about the cheapest thing you can do
considering the cost of man-hrs
and based on the idea that:
"what one cleaner cannot dissolve, another one might".
Re: The famous Neon rough idle question... [Re: 360view] #1632697
06/22/14 11:48 PM 06/22/14 11:48 PM
Joined: Mar 2005
Posts: 1,630
North Central Florida
E
eightlitermopar Offline OP
top fuel
eightlitermopar  Offline OP
top fuel
E

Joined: Mar 2005
Posts: 1,630
North Central Florida
Quote:

You might try directing some propane from an unlit torch into the intake to the air filter after the engine is fully warmed up.
(when started cold the air fuel ratio is very rich anyway)

If one or more of your fuel injector tips have deposit build ups interfering with the short solenoid plunger up down at idle, the extra propane should smooth out the idle.

If the IAC is working correctly it should adjust while this is happening and RPM should keep returning to spec as the propane is quickly added or taken away.

While you have the propane torch out check for air leaking past gaskets or o- rings.r

Carbon deposits on the backsides of intake valves can also cause a rough idle.

If you are going to keep driving it
add a bottle of Chevron Techron Plus to your next tank,
a bottle of Gumout Regane to the 2nd tank,
then a bottle of Redline SI-1 to the third tank.

This is about the cheapest thing you can do
considering the cost of man-hrs
and based on the idea that:
"what one cleaner cannot dissolve, another one might".



The car runs great above 800 RPM. I will try some of the additives to see if that helps.

I'll let you know if anything changes, but I am accepting the fact that I just might have a slightly rough idle for the rest of the days I own this car. With the cost of cars going up and up, I plan on driving this car into the ground.

Mopar or no car
Re: The famous Neon rough idle question... [Re: eightlitermopar] #1632698
07/08/14 03:24 PM 07/08/14 03:24 PM
Joined: Mar 2005
Posts: 1,630
North Central Florida
E
eightlitermopar Offline OP
top fuel
eightlitermopar  Offline OP
top fuel
E

Joined: Mar 2005
Posts: 1,630
North Central Florida
So, here is my latest update.

The car was running very rough at idle and seems to be getting worse. When the car is in “drive” at idle, it started developing a loud “chirping” sound that gradually got louder.

I took it back to the shop that did the timing belt, water pump, and replaced 2 motor mounts.

Long story short: The new motor mount/strut on the passenger side of the motor was adjusted properly (front to back), but the adjustment (side to side) was a little close to the motor. It was just enough that the idle would cause it to make contact and really vibrate the car.

After a readjustment, it idles A LOT smoother. However, there still is a bit of a shake at idle, but nothing close to what it was. They claim that if I replaced all of the mounts, it would smooth out like a new neon.

Based on what I experienced just with just one properly adjusted mount/strut, I totally believe it.

Mopar or no car
Page 3 of 3 1 2 3

Moderated by  Al_Alguire, Hotwheelsjr, moparts, not_a_charger, RangerDan440, tboomer 
Privacy Policy · Forum Rules · Mark All Read Contact Us · Moparts




Moparts Main Index | READ - Info & Help Page | Moparts Sponsors | Tech Archive


Powered by UBB.threads™ PHP Forum Software 7.7.1