1985 Cadillac Deville Engine low idle.Engine dies when car

1985 CADILLAC DEVILLE
106,000 MILES • V8 • FWD • AUTOMATIC
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DAVID C5996
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I bought the car 4 months ago.The engine was racing all the time.I replaced the TPS sensor.Engine now runs,but idles really slow,at times it will die in traffic,particularly when stopped at a signal or in traffic for a long period of time.When I shift into PARK the RPMs don't change.It also acts sluggish for an instant when accelerating.Also,on a different note,My right turn signal quit working.With the headlights on,the R Turn dash indicator stays on.With headlightss off,the indicator comes on when turning signal switch is set for R Turn.Left turn signal is fine.
Feb 13, 2010 at 2:02 AM
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BUDDYCRAIGG
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I can help about the light problem.
the front marker light has lost it's ground.
Like a bad wire, or a corroded socket. or simply a bad bulb.
Feb 13, 2010 at 2:15 AM
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DAVID C5996
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Would this be true,even if the right marker light lights up when Rturn switch is switched for R turn.Both the left and right "outside illuminating lights work when turn signal switch is switched,but right bturn lights front and back don't work.
Feb 13, 2010 at 2:22 AM
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BUDDYCRAIGG
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could re-word that, I didn't follow it.
Feb 13, 2010 at 2:29 AM
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DAVID C5996
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When the Turn signals are activated,the side lights that illuminate the corner area of the car and surrounding ground will come on,but the Right turn signal won't come on.Left turn signal will come on.Hope this helps.
Feb 13, 2010 at 2:35 AM
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BUDDYCRAIGG
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yep, still what i said earlier
Feb 13, 2010 at 2:41 AM
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DAVID C5996
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Thank you for the info. I appreciate it. Now, do you know anyone who can help me with my engine problem?
Feb 13, 2010 at 2:56 AM
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BUDDYCRAIGG
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if you have a service manual for the car, it should tell you how to adjust the Idle Control Motor.

That's where I would start.
Feb 13, 2010 at 6:17 PM
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DAVID C5996
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One more question.How would you check RPMs on a car of this type ignition system?I know how on the older cars,as I recall,you hook a tach-dwell meter between plug #1 and ground and set meter for 8 cyl. At least I think thats it.
Feb 14, 2010 at 1:50 AM
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BUDDYCRAIGG
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I think you still have an old school HEI distributor cap.
it has a bump on one side that has...
a power connector
a tach connector
and then a 3 wire plug for the control moduel.

you can hook the tach up to the terminal labeled "tach"
Feb 14, 2010 at 9:49 PM
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DAVID C5996
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Thank you for the info.I'll check it out.
Feb 15, 2010 at 1:35 AM
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2 LINSEY
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We appreciate your donation and look forward to helping you in the future. Thank you
Mar 1, 2010 at 4:36 PM
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