Login Register

940 stalls at Hwy speed - 2 quick questions

Help, Advice, Owners' Discussion and DIY Tutorials on all Volvo's "mid era" rear wheel drive Volvos.

1975 - 1993 240
1983 - 1992 740
1982 - 1991 760
1986 - 1991 780
1990 - 1998 940
1990 - 1998 960
1997 - 1998 V90/S90

Post Reply
macs70GLT
Posts: 86
Joined: 25 September 2009
Year and Model: S70 GLT 1998
Location: Maple Valley, WA

Update: 940 stalls at Hwy speed - 2 quick questions

Post by macs70GLT »

Spoke too soon.
Car stalled again yesterday while my son was driving, he pulled over & it started up again.
I drove it to work today, it tried to stall but I feathered the gas & kept the motor running, still had to pull over while doing it.
Tonight I resoldered the connections on the Fuel Pump Relay. Seems a little smoother on short drive, but still slightly hunting idle.
Previously I had replaced plugs, cap & rotor, air filter, reinstalled the Ignition Amp with thermal compound, no codes set by the Fuel or Ignition systems on the diagnostics.
Next I'm going to check the Crank Speed Sensor (I have a new one, also new pump relay & plug wires coming from IPD).

Is there an easy way to check the fuel injectors? I have a wire harness with LED I made a few years ago to check the wires for the injectors, but I would like to see how the injectors themselves are performing.

Thanks for the input.

Mike
Lars: 1988 245, 250K mi retired
Son of Lars: 1998 S70 GLT, 225K mi retired
Beast Mode: 1995 940T, 213K mi
Son's car: 1998 V70 GLT, 182K mi
Hans: 2002 Audi A4 QMT, 142K mi

dbooth914
Posts: 11
Joined: 6 April 2014
Year and Model: 1996 850
Location: San Diego, CA

Post by dbooth914 »

Any update on this issue? I have a 96 850 doing the same thing, dies on the freeway at speed. Scary. I don't think my wife or daughter will ever drive it again!

--Doug

macs70GLT
Posts: 86
Joined: 25 September 2009
Year and Model: S70 GLT 1998
Location: Maple Valley, WA

Post by macs70GLT »

Hi Doug,

I think the ignition amplifier was the main contributor for my 940 stalling issue.

More recently I finally found the vacuum leak which made it idle rough; bad intake manifold gasket. It runs much better after replacing that along with cleaning the IAC valve and throttle intake.

Mike
Lars: 1988 245, 250K mi retired
Son of Lars: 1998 S70 GLT, 225K mi retired
Beast Mode: 1995 940T, 213K mi
Son's car: 1998 V70 GLT, 182K mi
Hans: 2002 Audi A4 QMT, 142K mi

dbooth914
Posts: 11
Joined: 6 April 2014
Year and Model: 1996 850
Location: San Diego, CA

Post by dbooth914 »

Hi Mike,

I just got back to this thread. I have been chasing this issue as a fuel delivery problem, as it feels like the car is running out of gas, although there is gas in the tank. If I am driving, i can slip into neutral, feather the gas and keep it running, which again seems like a fuel problem.

I can also say that it only happens after the car is fully warmed up, so maybe it is electrical. The care will start in a minute or so, and the issue always passes never left anyone stranded. The car runs well the rest of the time.

Just so I'm clear, you replaced your ignition amplifier and the problem has not returned?

Thanks,

--Doug

lummert
Posts: 1381
Joined: 29 January 2008
Year and Model: 760 1988
Location: Portland Indiana, USA
Been thanked: 26 times

Post by lummert »

I had operating temp stalling and irratic tach behavior when the power stage (ignition module) was going bad on my 1988 Volvo 760 Turbo.
1988 Volvo 760 Turbo Wagon

Post Reply
  • Similar Topics
    Replies
    Views
    Last post