1995 855 NA: Sudden stall/off while idling

lcc014 · Post by **lcc014** » 03 Feb 2025, 07:26

The sudden stall/off (similar to shut off) incident happened 3 times since early last week. The first time was in last week, early in the morning after I started the car on driveway to warm up the car in cold morning. When I went back to the car from house, the car was already "stopped". All the dash lights were on. I restarted the car and it started without any issue. The second and third incidents were this morning in my driveway and then when I was at the company parking garage entrance, stopped for scanning the parking card. Car was not shaking before shutting off. It was idling. No CE or any other light was triggered. I could restart the car immediately without issue. Driving was fine.

Any suggestion to debug this issue.

Thanks,

Ching-Ho Cheng

Post by **abscate** » 04 Feb 2025, 02:43

When were cap, rotor, and plugs last changed ?

Make sure the idle control valve is clean and the connector is tight and Clean.

It does sound a bit like an electrical bus failure, but start with Stage0, then move to battery cables, and ignition switch, electrical part.

Let us know if you need help finding those parts

lcc014 · Post by **lcc014** » 04 Feb 2025, 16:04

abscate wrote: ↑04 Feb 2025, 02:43 When were cap, rotor, and plugs last changed ?

Make sure the idle control valve is clean and the connector is tight and Clean.

It does sound a bit like an electrical bus failure, but start with Stage0, then move to battery cables, and ignition switch, electrical part.

Let us know if you need help finding those parts

The Cap, Rotor and Spark Plug wires were replaced back in 8/2021 (around 405K miles).
Both ICV (IAC) and throttle cable were replaced back in 7/2020 (around 397K miles).
The spark plugs were replaced back in 4/2020 (around 396K miles).
Fixed the lose connection between battery (+ve) and fuse box back in 5/2013 (around 275k Miles).
Replaced ignition switch back in 9/2010 (around 234k Miles).

Car's current mileage is about 446K miles.

Thanks,

Ching-Ho Cheng

Post by **scot850** » 04 Feb 2025, 17:10

What spark plugs are you using? They are probably passed their best at 50k miles.

It is unfortunately time to go through the basics. Test the fuel pressure for around the 43 psi range.

IAC with a high mileage engine may need cleaned from time to time. It is unlikely needing replaced at this mileage. While there, check the throttle body is not needing cleaned.

I am for now ignoring the coolant sensor causing cold start issue, as you had a fail after a drive.

When was your MAF last replace/cleaned. This issue reminds me of a friends car just before the MAF failed completely. Random issue running when cold and then increasing to when running. Check the connector on the MAF is not corroded. The one on that car I mentioned was a nice green furry color!

Neil.

lcc014 · Post by **lcc014** » 04 Feb 2025, 18:51

scot850 wrote: ↑04 Feb 2025, 17:10 What spark plugs are you using? They are probably passed their best at 50k miles.

It is unfortunately time to go through the basics. Test the fuel pressure for around the 43 psi range.

IAC with a high mileage engine may need cleaned from time to time. It is unlikely needing replaced at this mileage. While there, check the throttle body is not needing cleaned.

I am for now ignoring the coolant sensor causing cold start issue, as you had a fail after a drive.

When was your MAF last replace/cleaned. This issue reminds me of a friends car just before the MAF failed completely. Random issue running when cold and then increasing to when running. Check the connector on the MAF is not corroded. The one on that car I mentioned was a nice green furry color!

Neil.

Neil,

Thank you for the prompt response. All the parts that I used for my Volvo were genuine Volvo parts (from dealer, Boston Volvo or FCPEuro). Also, I used Volvo 5 prone spark plugs all the times and the Volvo wires.
- Fuel pump was replaced back in 10/2013 (around 283K miles). I could not start the car not matter how hard I tried to start it.
- Ignition coil was replaced back in 10/2010 (around 236k Miles). Coil was made by Bosch.
- Coolant temperature sensor was replaced back in 7/2020 (around 397K Miles).
- MAF sensor was replaced back in 6/2009 (around 209K Miles).

For MAF sensor symptom, I had experience with that. Car was shaking and lack of power during acceleration. Car also wanted to stall too.

My Volvo current symptom is to stall during idling - waiting for traffic light, car warm up in the morning or traffic jam on highway, etc. It was so random that I could not predict when will it stall. When car was driving on highway or city road, it behaved normal, not sign of stalling or running rough.

I don't have the fuel pressure gauge to check the fuel pressure.

Thanks,

Ching-Ho Cheng

Post by **scot850** » 04 Feb 2025, 20:56

A cheap tire pressure gauge of the stick type can be used to check pressure using the fuel rail Shraeder valve. Turn the ignition on to 2 so you can hear the pump prime (hopefully!). Then test the pressure. Not really accurate but if you see say 36psi or higher it should start and run. It will damage the gauge but no big deal. Try again with engine started to see what pressure it suns with.

Try jumping the fuel pump relay and see if that makes a difference. Short term only for testing purposes!

MAF has been replaced, but not immune to failing again. Try disconnecting the wire connector to it and see what happens.

I'm happy to be corrected but Volvo plugs on those older engines were due changed at 30k miles, unless you have info saying different.

Having said that, if the car runs, worn plugs may cause loss of power but not typically killing an engine that is running.

Then it is down to checking vacuum lines, cleaning the MAF/IAT and throttle body and see what they are like.

Lastly, open the distributor cap and check there is no condensation in there or corroded tips on the cap and rotor.

It is a process.....!

Then it is on to cam/crank position sensors.

Neil.

Post by **abscate** » 05 Feb 2025, 03:50

I forgot the fuel pump relay , they do fail sporadically so thst could be the issue

lcc014 · Post by **lcc014** » 05 Feb 2025, 15:29

scot850 wrote: ↑04 Feb 2025, 20:56 A cheap tire pressure gauge of the stick type can be used to check pressure using the fuel rail Shraeder valve. Turn the ignition on to 2 so you can hear the pump prime (hopefully!). Then test the pressure. Not really accurate but if you see say 36psi or higher it should start and run. It will damage the gauge but no big deal. Try again with engine started to see what pressure it suns with.

Try jumping the fuel pump relay and see if that makes a difference. Short term only for testing purposes!

MAF has been replaced, but not immune to failing again. Try disconnecting the wire connector to it and see what happens.

I'm happy to be corrected but Volvo plugs on those older engines were due changed at 30k miles, unless you have info saying different.

Having said that, if the car runs, worn plugs may cause loss of power but not typically killing an engine that is running.

Then it is down to checking vacuum lines, cleaning the MAF/IAT and throttle body and see what they are like.

Lastly, open the distributor cap and check there is no condensation in there or corroded tips on the cap and rotor.

It is a process.....!

Then it is on to cam/crank position sensors.

Neil.

Thank you. I will open up the distributor cap and check the condition. Also, try to get hold of a fuel pressure gauge to check the pressure.

Ching-Ho Cheng