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Stalling after warming up

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Old Sep 22, 2025 | 05:05 PM
  #1  
Viking87's Avatar
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From: Manitoba
1995 S420
Stalling after warming up

Has anyone experienced this symptom? See other threads by this ID for full version of what is going on.

Basically once the car warms up to operating temperature it stalls and is hard to restart. Works fine from cold. New radiator cap, thermostat and rad flushed has already been applied. Check engine light was already on. There is a connection stuck open that prevents use of a code reader. This was already a problem prior to over heating / hose fitting failure adventure.

Just looking for potential sources. Gasket failure already on the table as a possible cause.

Reply here or in original thread.
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Old Sep 22, 2025 | 05:31 PM
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'13 s212 63 p30. '06 LX470
Vacuum or fuel pressure regulator or MAF? Have you tested for fuel pressure or vacuum leaks?
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Old Sep 23, 2025 | 02:21 PM
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Sorry but what is a MAF?

Have not tested for fuel pressure or vacuum leak. Beyond my mechanical knowledge/capacity.

The fuel filter was reasonably priced on internet. Guess it never hurts to replace filters. Am pretty sure it hasn't been done by previous owner.

Just harvesting ideas for what it might be. Was leaning towards head gasket failure but low fuel pressure would seem to be a potential cause/explanation as well.

Thank you for the reply.
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Old Sep 27, 2025 | 09:21 AM
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'13 s212 63 p30. '06 LX470
Originally Posted by Viking87
Sorry but what is a MAF?

Have not tested for fuel pressure or vacuum leak. Beyond my mechanical knowledge/capacity.

The fuel filter was reasonably priced on internet. Guess it never hurts to replace filters. Am pretty sure it hasn't been done by previous owner.

Just harvesting ideas for what it might be. Was leaning towards head gasket failure but low fuel pressure would seem to be a potential cause/explanation as well.

Thank you for the reply.
The mass airflow sensor, which is on the intake pipe. The tools to test the fuel pressure or for intake leaks is pretty inexpensive vs If you had to go pay someone else an hour or two of labor to do that.. running comes down to air, spark, and fuel. The air and the fuel need to be in line in order for the spark to efficiently combust the gases.

check it out on YouTube, but sometimes you can see if the maf is the issue by disconnecting it.
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Old Sep 27, 2025 | 03:40 PM
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1995 S420
Thanks Baltistyle

Found the part you are referencing. Comes with a how to video.

Will add it to the list of potential culprits for the garage/neighbor assistance.

These are not cheap so won't be replacing on speculation.


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Old Sep 27, 2025 | 07:09 PM
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'13 s212 63 p30. '06 LX470
Originally Posted by Viking87
Thanks Baltistyle

Found the part you are referencing. Comes with a how to video.

Will add it to the list of potential culprits for the garage/neighbor assistance.

These are not cheap so won't be replacing on speculation.

Yep, you can test it, monitor it with the right tools. First try unplugging it as thats an easy test.
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