Volvo 850 Lambda Light flashes and Engine hesitates

[DR Gibson]

Dear Group,

I have a Volvo 850 GLT Estate 2.5 20 valve, UK L registration c.1994. At
times the dashboard Lambda Light flashes and the engine hesitates, sometimes
just once, and at others many times in succession. This usually happens on
a run once the engine has heated up and more at higher speeds, mainly on a
very light throttle, much less with a heavy throttle, rarely under full
deceleration and breaking.

I have the Haynes workshop manual, and I checked the diagnostic module
sockets and fault codes:

Module A Socket 6:
3 - 2 - 4 Camshaft position sensor absent intermittently.
2 - 1 - 4 RPM (crankshaft) sensor signal absent intermittently


Module A Socket 2 (Jetronic):
1 - 3 - 1 Engine RPM signal from ignition system absent or faulty.

Will replacing the Camshaft and or RPM sensors cure the problem, please, or
do you think the fault lies elsewhere? I would like to do the work myself
if it is not too daunting.

God bless,

David

 

[Tim..]

Dear Group,

I have a Volvo 850 GLT Estate 2.5 20 valve, UK L registration c.1994. At
times the dashboard Lambda Light flashes and the engine hesitates,
sometimes
just once, and at others many times in succession. This usually happens
on
a run once the engine has heated up and more at higher speeds, mainly on a
very light throttle, much less with a heavy throttle, rarely under full
deceleration and breaking.

I have the Haynes workshop manual, and I checked the diagnostic module
sockets and fault codes:

Module A Socket 6:
3 - 2 - 4 Camshaft position sensor absent intermittently.
2 - 1 - 4 RPM (crankshaft) sensor signal absent intermittently


Module A Socket 2 (Jetronic):
1 - 3 - 1 Engine RPM signal from ignition system absent or faulty.

Will replacing the Camshaft and or RPM sensors cure the problem, please,
or
do you think the fault lies elsewhere? I would like to do the work myself
if it is not too daunting.

Yes, camshaft sensor is a fairly common failing.. check the connector and
make sure it is not oil soaked too.
tim