.

Jump to content


Hello, Allpar Forums member or visitor! If you were an active member (more than two posts) or subscriber, you would not see this ad!

Register for a free account or Sign in (see top right of page for Facebook/Open ID login icons).


Photo
- - - - -

'93 Lebaron 3.0 Won't Idle


This topic has been archived. This means that you cannot reply to this topic.
7 replies to this topic

#1 DECA

DECA
  • Active Member
  • 26 posts

Posted May 27, 2011 at 06:16 pm

Hi All. My Daughter calls Me last nite saying Her car broke down. Won't stay running. I go find Her & it seems like its running on 3 0r 4 cylinders But If I give it gas it's smooth at about 2k rpm. Unplugged MAP sensor & it got worse. Played with it for a half hour & finally Had it towed to Pep Boys & after I rolled it off the rollback it started & idled fine. They ran it for 2 hours today with no codes & no problem. Maybe a bad Coolant temp sensor? I did the timing belt ,w/pump, Hoses, 180 degree thermostat 2 weeks ago. It's got 112k miles on it.

#2 billccm

billccm
  • Active Member
  • 768 posts

Posted May 28, 2011 at 08:59 pm

I'll think about this, but I believe on OBD1 cars, misfire from the ignition system does not give a code. Therefore, I would suspect an intermittent Hall PIck up in the distributor.

Let me know if you come up with any additional clues.

Good Luck, Bill

#3 John Wood

John Wood
  • Active Member
  • 10,706 posts

Posted May 29, 2011 at 04:16 pm

when did it last have new cap, rotor, wires and plugs? Moisture on the wires can cause intermittent firing. At least make sure you've got that covered before digging further. There is no Hall effect pickup on a 93, 3.0, but there is a crankshaft position sensor instead. Those have been known to become intermittent and throw no codes. Consider replacing that if there are no other clues and all your ignition parts are up to snuff. Also, consider the fuel filter and possibly even the fuel pump if the car has high mileage.

Sometimes a no idle can be a stuck EGR valve (stuck open) or a dirty throttle body or faulty idle control motor (clean all contacts if this is suspected).

#4 george w

george w
  • Supporters III
  • 954 posts

Posted May 30, 2011 at 08:19 am

I don't believe there's a crankshaft position sensor on your car. Also, the coolant temp sensor won't have any real effect on the idle. If the cars seems to run OK at the higher rpms then I would also suspect that the ignition components are at least passable.

The first thing I would check is the throttle body and the AIS motor. It's easy enough to remove the throttle body and make sure it's clean. I'd also remove the AIS motor and make sure the pintle and shaft are clean. Cleaning with the TB on the car and spray cleaner just won't cut it if there's any kind of build up. You've got to remove the TB and clean it throughly. Some cleaning solvent and and old toothbrush works wonders. Also check immediately inside the plenum opening once the TB is removed and make sure there isn't a pile of gunk built up at the EGR opening which is just past the TB.
You could have a combination a really dirty throttle body and a sticking or bad AIS which will cause this problem and not set any codes. Onve you have the TB cleaned up and reinstalled try to start the car. You can confirm that the AIS motor is working if the car starts and runs up to about 1500 rpm and then settles down in a few seconds. If you see no idle speed change at startup or a change in idle speed when you turn on the A/C then you can suspect the AIS motor to be bad.

Hope you find your problem.

#5 John Wood

John Wood
  • Active Member
  • 10,706 posts

Posted May 30, 2011 at 11:51 am

I don't believe there's a crankshaft position sensor on your car. Also, the coolant temp sensor won't have any real effect on the idle. If the cars seems to run OK at the higher rpms then I would also suspect that the ignition components are at least passable.

The first thing I would check is the throttle body and the AIS motor. It's easy enough to remove the throttle body and make sure it's clean. I'd also remove the AIS motor and make sure the pintle and shaft are clean. Cleaning with the TB on the car and spray cleaner just won't cut it if there's any kind of build up. You've got to remove the TB and clean it throughly. Some cleaning solvent and and old toothbrush works wonders. Also check immediately inside the plenum opening once the TB is removed and make sure there isn't a pile of gunk built up at the EGR opening which is just past the TB.
You could have a combination a really dirty throttle body and a sticking or bad AIS which will cause this problem and not set any codes. Onve you have the TB cleaned up and reinstalled try to start the car. You can confirm that the AIS motor is working if the car starts and runs up to about 1500 rpm and then settles down in a few seconds. If you see no idle speed change at startup or a change in idle speed when you turn on the A/C then you can suspect the AIS motor to be bad.

Hope you find your problem.


George, you're right. That year 3.0 used the optical distributor to determine the crankshaft position. The CPS came on later 3.0's with OBD II based systems. Thanks for the reminder and correction.

Edited by John Wood, May 30, 2011 at 11:56 am.


#6 DECA

DECA
  • Active Member
  • 26 posts

Posted June 4, 2011 at 06:06 am

Thanks for the help. I think it was the EGR valve as it hasn't happened since I replaced it. Also cleaned throttle body & replaced temp sensor & TPS because it seemed to hesitate a little when cold.

#7 ImperialCrown

ImperialCrown
  • Supporters
  • Others:Forum Leader
  • 12,245 posts

Posted June 4, 2011 at 07:19 am

When you ran it with the MAP sensor unplugged, that should have set a MAP fault code?

#8 DECA

DECA
  • Active Member
  • 26 posts

Posted June 4, 2011 at 12:23 pm

When you ran it with the MAP sensor unplugged, that should have set a MAP fault code?


That's what I thought. I even told pepboys when they pull the codes it should show a map sensor code but to keep looking. 12 & 55 are the only codes
I think 12 is from when I unhooked the battery to do timing belt & 55 is end of codes.


.
Allpar

Home · Cars · Engines · Repairs · Tool and Car Reviews · News

Please read the terms of use and privacy policy. We are not affiliated with Chrysler Group, makers of cars, minivans, trucks, and Mopar (TM) parts. We make no guarantees regarding validity or applicability of information, opinions, or advice. Posts may be edited and used in other parts of allpar.com and affiliated car-related sites. We have the right to remove or modify any message, and to ban or suspend any user without notice. Logos and site-specific information copyright © 2001-2014 Allpar LLC; Chrysler PR materials remain property of Chrysler Group.