# automotive question

**URL:** <https://boards.straightdope.com/t/automotive-question/228971>\
**Category:** Factual Questions\
**Created:** [February 13, 2004, 2:22am UTC](https://boards.straightdope.com/t/automotive-question/228971 "2004-02-13T02:22:34Z")\
**Posts on this page:** 10\
**Page:** 1

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**Author:** ![pope\_hentai](https://avatars.discourse-cdn.com/v4/letter/p/ee59a6/32.png) [@pope\_hentai](https://boards.straightdope.com/u/pope_hentai)\
**Post date:** [February 13, 2004, 2:22am UTC](https://boards.straightdope.com/t/automotive-question/228971/1 "2004-02-13T02:22:34Z")

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i’m driving a 1986 pontiac sunbird wagon and when the engine warms up after a little while on the road it will stall out at a stop unless i give it a bit more gas. what causes this and how do i fix said problem?

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**Author:** ![SlickRoenick](https://avatars.discourse-cdn.com/v4/letter/s/e68b1a/32.png) [@SlickRoenick](https://boards.straightdope.com/u/SlickRoenick)\
**Post date:** [February 13, 2004, 2:27am UTC](https://boards.straightdope.com/t/automotive-question/228971/2 "2004-02-13T02:27:11Z")

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Is it automatic or manual transmission?

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**Author:** ![pope\_hentai](https://avatars.discourse-cdn.com/v4/letter/p/ee59a6/32.png) [@pope\_hentai](https://boards.straightdope.com/u/pope_hentai)\
**Post date:** [February 13, 2004, 2:34am UTC](https://boards.straightdope.com/t/automotive-question/228971/3 "2004-02-13T02:34:31Z")

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automatic. knew i forgot a detail _L_

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**Author:** ![Tentacle\_Monster](https://avatars.discourse-cdn.com/v4/letter/t/ba9def/32.png) [@Tentacle\_Monster](https://boards.straightdope.com/u/Tentacle_Monster)\
**Post date:** [February 13, 2004, 2:49am UTC](https://boards.straightdope.com/t/automotive-question/228971/4 "2004-02-13T02:49:15Z")

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\<hijack\>

Hey, pope, you got a buddy in the Air Force? Goes by kisama? Went into computer programming and now lives in Texas?

Shoot an email to mmercer22_at_adelphia_dot_net. He said he had a buddy who went by your username. I want to know whether or not it’s you.  
\</hijack\>

On the OP… I got nothin’.

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**Author:** ![MadScientistMatt](https://avatars.discourse-cdn.com/v4/letter/m/bc8723/32.png) [@MadScientistMatt](https://boards.straightdope.com/u/MadScientistMatt)\
**Post date:** [February 13, 2004, 3:23am UTC](https://boards.straightdope.com/t/automotive-question/228971/5 "2004-02-13T03:23:05Z")

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There’s lots of different possible causes - the most likely one on a car from that age with miles of degrading rubber hoses under its hood is a vacuum leak. I’d replace any old or brittle vacuum hoses under the hood first. A “band-aid” way to prevent it from stalling is to increase the idle speed.

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**Author:** ![pope\_hentai](https://avatars.discourse-cdn.com/v4/letter/p/ee59a6/32.png) [@pope\_hentai](https://boards.straightdope.com/u/pope_hentai)\
**Post date:** [February 13, 2004, 3:35am UTC](https://boards.straightdope.com/t/automotive-question/228971/6 "2004-02-13T03:35:40Z")

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i’ve already replaced most if not all of the hoses. i’ll hafta check with my dad/mechanic to see whiche ones were left. if thats not it what would the next step be?

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**Author:** ![pope\_hentai](https://avatars.discourse-cdn.com/v4/letter/p/ee59a6/32.png) [@pope\_hentai](https://boards.straightdope.com/u/pope_hentai)\
**Post date:** [February 13, 2004, 1:40pm UTC](https://boards.straightdope.com/t/automotive-question/228971/7 "2004-02-13T13:40:40Z")

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one more question how do i check the lines to see which ones leaking?

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**Author:** ![Enola\_Straight](https://avatars.discourse-cdn.com/v4/letter/e/dec6dc/32.png) [@Enola\_Straight](https://boards.straightdope.com/u/Enola_Straight)\
**Post date:** [February 13, 2004, 4:46pm UTC](https://boards.straightdope.com/t/automotive-question/228971/8 "2004-02-13T16:46:04Z")

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I believe mechanics use a smoker machine to blow smoke under pressure into the intake manifold. Wherever a squirt of smoke comes out indicates a leak.

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**Author:** ![danceswithcats](https://avatars.discourse-cdn.com/v4/letter/d/9e8a1a/32.png) [@danceswithcats](https://boards.straightdope.com/u/danceswithcats)\
**Post date:** [February 13, 2004, 6:20pm UTC](https://boards.straightdope.com/t/automotive-question/228971/9 "2004-02-13T18:20:40Z")

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Since your problem occurs at idle, I’d speculate the TPS or Throttle Position Sensor is giving intermittant feedback to the ECM owing to wear. I’ve replaced that device on my truck which is an '85 owing to similar symptoms.

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**Author:** ![El\_Cid\_Viscoso](https://avatars.discourse-cdn.com/v4/letter/e/41988e/32.png) [@El\_Cid\_Viscoso](https://boards.straightdope.com/u/El_Cid_Viscoso)\
**Post date:** [February 13, 2004, 7:23pm UTC](https://boards.straightdope.com/t/automotive-question/228971/10 "2004-02-13T19:23:59Z")

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Hello **pope\_hentai** ,

Beyond what **danceswithcats** has said, two things I’ve experienced sound consistent with this behavior:

1. Check out your fuel cap/fuel filler pipe. If your cap is nonexistent, loose or rusted, or if your filler pipe is perforated by rust or damage, your car may lose fuel pressure.

2. Your fuel filter may be old and clogged. Further, your fuel pump might be on the fritz. Has your fuel system ever been checked out?

Standard caveats apply. If you get your car up on a mechanic’s rack and they look at your fuel system, it will generally end up requiring some parts/labor. If you know a mechanic you can really trust, he or she should be able to diagnose fuel pressure issues without a lot of heavy lifting.  
.
