# Car limp mode and engine light on

**URL:** <https://community.cartalk.com/t/car-limp-mode-and-engine-light-on/182712>\
**Category:** Maintenance/Repairs\
**Tags:** transmissions, volkswagen, passat, engines, lights\
**Created:** [February 27, 2022, 9:49pm UTC](https://community.cartalk.com/t/car-limp-mode-and-engine-light-on/182712 "2022-02-27T21:49:18Z")\
**Posts on this page:** 13\
**Page:** 1

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**Author:** ![Ankurpatel113](https://avatars.discourse-cdn.com/v4/letter/a/f07891/32.png) [@Ankurpatel113](https://community.cartalk.com/u/Ankurpatel113)\
**Post date:** [February 27, 2022, 9:49pm UTC](https://community.cartalk.com/t/car-limp-mode-and-engine-light-on/182712/1 "2022-02-27T21:49:18Z")

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Hi all,

I have 2014 Volkswagen Passat 3.6l  
I was driving and all of sudden car acceleration went down below 40 Kmph and could not accelerate it over that speed and check engine light went on. I think that’s car limp mode.

Can you guys tell me what might cause that as i do not know much about car repairs? I shut down car for few minutes and looks like limp mode is gone and engine light turned off but what do you recommend? Should I take it to mechanic? Or is there anything I can check and fox by myself?

I got the alarm codes, I had p0420 before as well I also got 17130 Pressure control P0746

Thank you in advance.

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**Author:** ![Tester](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/tester/32/15976_2.png) [@Tester](https://community.cartalk.com/u/Tester)\
**Post date:** [February 27, 2022, 9:52pm UTC](https://community.cartalk.com/t/car-limp-mode-and-engine-light-on/182712/2 "2022-02-27T21:52:26Z")

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First thing that needs to be done is, pull the codes to determine what caused the Check Engine light to turn on

Tester

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**Author:** ![VDCdriver](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/vdcdriver/32/30_2.png) [@VDCdriver](https://community.cartalk.com/u/VDCdriver)\
**Post date:** [February 27, 2022, 9:57pm UTC](https://community.cartalk.com/t/car-limp-mode-and-engine-light-on/182712/3 "2022-02-27T21:57:14Z")

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> [@Ankurpatel113](#):
>
> is there anything I can check and fox by myself?

> [@Ankurpatel113](#):
>
> i do not know much about car repairs

As Tester mentioned, what is needed at this point is to have the _Diagnostic Trouble Codes_ “read”. In the US, most auto parts stores will do this without charge, but I don’t know if that is the case in your country.

As to what you can fix by yourself, with all due respect, since you admit that you don’t know much about car repairs, I don’t think you have any alternative but to take it to a competent mechanic’s shop for repair. Since the car won’t cure itself, continuing to drive it could cause a relatively inexpensive repair to morph into a very expensive repair.

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**Author:** ![Ankurpatel113](https://avatars.discourse-cdn.com/v4/letter/a/f07891/32.png) [@Ankurpatel113](https://community.cartalk.com/u/Ankurpatel113)\
**Post date:** [February 27, 2022, 10:24pm UTC](https://community.cartalk.com/t/car-limp-mode-and-engine-light-on/182712/4 "2022-02-27T22:24:17Z")

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Yes I got the trouble codes  
P0420 cat system efficiency which I had before too  
P0746 pressure control

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**Author:** ![Tester](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/tester/32/15976_2.png) [@Tester](https://community.cartalk.com/u/Tester)\
**Post date:** [February 27, 2022, 10:33pm UTC](https://community.cartalk.com/t/car-limp-mode-and-engine-light-on/182712/5 "2022-02-27T22:33:55Z")

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[https://www.transmissionrepaircostguide.com/p0746/](https://www.transmissionrepaircostguide.com/p0746/)

Tester

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**Author:** ![davepsinbox\_157004](https://avatars.discourse-cdn.com/v4/letter/d/73ab20/32.png) [@davepsinbox\_157004](https://community.cartalk.com/u/davepsinbox_157004)\
**Post date:** [February 27, 2022, 10:42pm UTC](https://community.cartalk.com/t/car-limp-mode-and-engine-light-on/182712/6 "2022-02-27T22:42:35Z")

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> [@Ankurpatel113](#):
>
> Or is there anything I can check and fox by myself?

Inasmuch as you have what appears to be a bad catalytic converter _and_ transmission problems, I doubt there’s anything you can do beyond preparing for a very large repair bill.

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**Author:** ![VOLVO-V70](https://avatars.discourse-cdn.com/v4/letter/v/8e8cbc/32.png) [@VOLVO-V70](https://community.cartalk.com/u/VOLVO-V70)\
**Post date:** [February 27, 2022, 10:48pm UTC](https://community.cartalk.com/t/car-limp-mode-and-engine-light-on/182712/7 "2022-02-27T22:48:34Z")

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> [@Ankurpatel113](#):
>
> Should I take it to mechanic?

Yes , because this is your third thread about this vehicle . So it is resonable to think that you will not be able to solve this .

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**Author:** ![bing](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/bing/32/4619_2.png) [@bing](https://community.cartalk.com/u/bing)\
**Post date:** [February 28, 2022, 4:27am UTC](https://community.cartalk.com/t/car-limp-mode-and-engine-light-on/182712/8 "2022-02-28T04:27:03Z")

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According to Tester’s post, I think you need to take it to an honest transmission shop. It may or may not be major if it is a solenoid. I had the sol pack replaced in my Olds when it went to limp mode and it cost somewhere around $250 for all four.

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<div class="post-metadata">

**Author:** ![Ankurpatel113](https://avatars.discourse-cdn.com/v4/letter/a/f07891/32.png) [@Ankurpatel113](https://community.cartalk.com/u/Ankurpatel113)\
**Post date:** [March 1, 2022, 4:04pm UTC](https://community.cartalk.com/t/car-limp-mode-and-engine-light-on/182712/9 "2022-03-01T16:04:31Z")

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Hi all,  
I took my car to couple of mechanics and they suggested me to take it to dealership and went to volkswagen today morning.  
As my limp mode was reset because car was off whole night they couldnt find any trouble codes, they could only get history of codes but during diagnosis they found a large vaccum leak and worn out serpentine belt.

Do you guys think vaccum leak is causing limp mode on?

Really appreciate your replies

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**Author:** ![Cavell](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/cavell/32/43396_2.png) [@Cavell](https://community.cartalk.com/u/Cavell)\
**Post date:** [March 1, 2022, 4:40pm UTC](https://community.cartalk.com/t/car-limp-mode-and-engine-light-on/182712/10 "2022-03-01T16:40:02Z")

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What was vac leak due too? How did they repair it?

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<div class="post-metadata">

**Author:** ![Ankurpatel113](https://avatars.discourse-cdn.com/v4/letter/a/f07891/32.png) [@Ankurpatel113](https://community.cartalk.com/u/Ankurpatel113)\
**Post date:** [March 1, 2022, 4:55pm UTC](https://community.cartalk.com/t/car-limp-mode-and-engine-light-on/182712/11 "2022-03-01T16:55:28Z")

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I have no idea, but thats what he said like had large vaccum leak and my serprentine belt was covered with oil. They had ordered gaskets and cover.

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<div class="post-metadata">

**Author:** ![Cavell](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/cavell/32/43396_2.png) [@Cavell](https://community.cartalk.com/u/Cavell)\
**Post date:** [March 1, 2022, 6:49pm UTC](https://community.cartalk.com/t/car-limp-mode-and-engine-light-on/182712/12 "2022-03-01T18:49:05Z")

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You can ask mechanic. Split hose? $5. Warped plastic intake? \>$5

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<div class="post-metadata">

**Author:** ![bing](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/bing/32/4619_2.png) [@bing](https://community.cartalk.com/u/bing)\
**Post date:** [March 1, 2022, 11:28pm UTC](https://community.cartalk.com/t/car-limp-mode-and-engine-light-on/182712/13 "2022-03-01T23:28:16Z")

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> [@Ankurpatel113](#):
>
> Do you guys think vaccum leak is causing limp mode on?

No. The code said a stuck solenoid in the transmission. Not having a current code means it is not currently stuck. Having a history code says that it was stuck. Attention needs to be paid to the solenoids. How would a belt cause that? You need to see a transmission shop.
