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Repair Questions and Answers.

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 #377764  by Wolff
 February 11th, 2019, 10:14 pm
I took the car for an 18 mile drive to rent a truck, and then 2 days later on sunday returned the truck and drove the 18 miles home, all fine, but then Monday morning I started it u p to go to work and it wouldn't idle, turned the key and it started right up and died, did it again but gave it a little gas and as long as I held the pedal down a little it would run, but as soon as I let the gas off it stalls.

3.5L engine, with 124k on it, air filter, fluids, cam and crank sensors, battery etc have been replaced last spring along with the plugs. I do a lot of short trips, I also know I have a code for the transmission solenoid pack which put it in limp mode a year ago when I was slowing down from 55-60, but I kept my speed 50 and below for this 18 mile trip and didn't have that happen, I doubt that issue would prevent the car from idling- it hasn't before.

I could use some ideas on what to check/look for as to a cause for the sudden non idle, thanks!
 #377766  by RealityChek1956
 February 12th, 2019, 12:42 am
Notice any "hissing" sounds while holding it at idle ...including from the brake pedal area inside the car ? (possible brake booster leak). Do a physical check of all the vacuum lines and the rubber elbow at the top of the throttle body. Short trips ? Not letting the engine fully warm up is not good for ANY engine especially in cold weather. Besides rust...condensation promotes sludge in the crankcase if you don't let it get fully warmed. If all checks good.....maybe a removal/cleaning of the throttle body might be due.
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 #377771  by Sneke_Eyez
 February 12th, 2019, 11:26 am
Possibly Idle Air Control Valve. I'd start with a throttle body cleaning, clean the IAC with IAC safe cleaner, see what happens.
If no improvement, try a swap to a new IAC - I've taken them from the junkyard and they've been good.
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 #377932  by Wolff
 February 25th, 2019, 10:42 pm
Well guys, an update on this-
I needed to use the car a few times to get to work on some really nasty days so I feathered the gas pedal enough to keep the tach around the normal idle speed.
Then a few days later it just suddenly was running normally all by itself and has been idling normally since and I did nothing to it!
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 #377935  by In-trepid
 February 25th, 2019, 11:01 pm
I always hate it when that happens. You just know that the problem will come back again. Well, good luck for now. I hope it stays fixed.
 #378457  by Spyder
 March 28th, 2019, 12:29 pm
If this problem "just suddenly" went away, you can bank it WILL be back. BECAUSE it went away, I am betting it's an IAC (idle air control) valve. Typically, when it does get stuck, you can give it a few SAFE raps with a small hammer, and it will "go away" again. Cleaning will help it live longer, but ultimately it will need to be replaced...
 #378470  by Countachqv
 March 29th, 2019, 12:46 pm
Did you ensure the accelerator pedal move freely? did you W40 the 2 cables to the throttle body? just take it out and clean it for good form. While doing that, if you never clean the plenum do that too. You'll be amazed how much crap that thing can hold. Change the valve as the others said and try this again. That should take care of all basics and probably this issue
 #378490  by user97
 March 30th, 2019, 6:56 pm
I know I am very late with my comment -- my money would be on EGR stuck slightly open. I had this happen on mine (did not through EGR code) -- not sure why -- the EGR position voltage was indicating slightly open.

Tapping on the EGR would cure the problem... Strangely enough, happened a few types enough for me to get a new EGR valve and did not happen since (hence not installed).