From JD

SSS factsheet:

Car model: 420sel
Year: 1987
Chassis Model: W126
Engine Model: 116?
Mileage(km/miles): 100230
State: NY
Last tune-up (km/miles):100000
-Spark plug: new
-S/P Cable: new
-Rotor: new
-Cap: new

What kind of sudden stalling do you experience?

-Deceleration: Not sure, was at a stop sign rolled through and she calmly stalled but started right up.

- Coasting: At 20mph or so a smooth stall, pulled over and started up again

- Crusing: Same as above


- Acceleration: Same as above

Does all the instrument and light are working in your dashboard?

-Temp gauge: Yes
-Oil pressure gauge:Yes
-Tachometer:Yes
-Fuel Gauge:Yes
-Alternator Gauge:Yes
-Abs light:Yes
-Srs light:Yes
-Engine light:Yes
-O2 sensor light:Yes
-all the other light :Yes
P.S. some model do not have a O2 light sensor but instead they have a check engine light.

STALLING INFO:

How often does it Stall:

She has only stalled on two consecutive days and day 3 no start, first day I rolled through a stop sign and she calmly and quietly shut off, I rolled to a stop and started her up as normal. Second day while doing about 20mph she simply and quietly shut down, pulled over and started as normal. NOW day 3 she is parked and will not start.

-At a certain outside temp(specify): winter in NY average 40 F

Does Any light come on or flikering before it Stall?: No
Engine Temp when stalling: Normal

Outside Temp when Stalling: Winter in NY average 40 F

Fuel gauge reading: Normal

Alternator's reading: Not sure

Ac/Heater on or off: Off

Heated seat on or off: N/A

Does it Start easy after Stalling:

The first two (days) times it stalled she started as if normal, the next day (3) sitting over night she does not start

After stalling when you get the engine running:

-The idle is smooth (specify RPM): Yes between 5-10
-The idle go up and down(specify RPM): No, steady RPM, as above

If the idle go up and down does it settle to normal after: Does not apply

Deceleration Stalling:

-If you put the car in neutral at the same time you decelerate does it stall?? N/A

- If you double pedal (one feet on the brake one feet one the throttle) and keep the RPM over 1500 does it stall?? N/A

Troubleshooting and Diagnostic

Which procedure have you follow to troubleshoot your problem? This fact sheet

Which part(s) have you replaced and why??

OVP, Voltage Regulator (had fluctuations and blew OVP fuse), cap, rotor, wires, plugs, fuel pump relay, fuel filter, just had the time and the parts. This was all replaced prior to stalling.


Do you do any other maintance to the car at same time??

No

How long since you fixe-it?

Did not fix, still can’t get car to start.

Comment:

I did notice after stalling the battery light was on? Could this be a failed or failing alternator, I did have to place the voltage regulator (located on alternator) about 300 miles ago because she broke down on me and blew the OVP fuse. So I replaced the Voltage regulator and OVP. She ran fine up to now. Possible coil? Vacuum leak?