V70 Stumble

Hi all,
I have a '98 V70 2.4. It has been running great, but recently it has
developed a slight stumble at idle. Hard to describe but it feels like
the ignition dies for just a split second, a cylindar (or maybe two?)
misfire, then everything is fine. It is very intermittant, only doing
it may be once or twice in a trip. At road speed there is no noticable
problems, and I get no codes.

I replaced the spark plugs and it doesn't feel as strong, but it is
still there. I plan to run some injector cleaner through her today on
the thought that it might be a sticking injector.

Any ideas as to what it might be, or how to isolate and identify the
problem, or is this one for the pros?

Bill

 

Bill,
No codes at all? Weird... The ECU should pick up any misbehaviour in
your engine. Have you had the code upgrade done to your ETM? I know
this is mostly to correct the CEL coming on but it might fix this as
well. Has it been unusually damp in your area like it has been here in
Ontario? I had a coil pack go bad a while back due to dampness. Covered
under warranty thankfully. Let us know what you find out!


Jordan 1999 S70 Loaded!

 

I had the same problem in a 2001 V70 and the following "recall" solved
it for free.

There is a "service campaign" for the electronic throttle system (ETS)
and electronic throttle module (ETM) where they actually put in a new
program that ignores errors by the ETM. If they need to replace the
ETM, it covers that. It is not techically a recall, but "VSC 155
service campaign".

Here is what the campaign covers:

"Electronic Throttle Module (ETM) failure may illuminate Electronic
Throttle System (ETS) light or MIL. Symptoms may include, uneven engine
idle, and/or "limp home mode" that could restrict vehicle speed to 10-30
miles per hour. Faults of the ETM are stored as DTCs in the ECM. If OBD
II detects a fault that might increase emissions, the MIL is
illuminated. Remedy: A software upgrade will be performed at the next
service interval, and ETM warranty extended to 10 years or 200,000
miles, whichever comes first."

It basically covers S70, V70, V70 XC, C70, S80, and S60 from 1999 to
2002.

For more information check page 2 of:

http://www.epa.gov/otaq/cert/recall/2006recallreport4.pdf

Obviously the question is, does this cover your 1998 V70. I would check
it out.

 

Thanks for the feedback guys. I will check with the dealer re: the
recall.

Regarding moisture, actually we are in our dryer season now, but in
Florida, what does that mean? : ) Maybe I need to apply a moisture
sealer to the cap and wires, or just replace them, but before I go too
far with the parts changing, I would like to be better informed.

Another question. If the control module does detect a problem, does it
always turn on a light on the dash, or does it just store it so that
you have to read it out with an ODBII reader? When I said no codes, I
actually meant no lights.

Bill

 

Usually a moisture problem shows up with trouble starting.

When my engine was stumbling on idle, there never was a signal sent to
the computer and no light came on. Other problems I had besides the
idle stumbling were hesitation when trying to accelerate and the cruise
control turning off.

Another possibility is the air flow mass meter, but the ETM (or TCM) fix
is free, so I would try that first.

 

1998 and back Volvo's can not be programmed or upgraded.
1999 up all Volvo's can be reprogrammed or updated.
At the age of your car, replace the ign, cap, ing rotor and plug wires.
Use Volvo plugs only.
Do not use Platinum plugs in any Volvo.
Volvo engines run like crap on Plat. plugs.
Use OEM or Bosch parts only.
BD

 

I really appreciate that info. The plugs that I pulled were platinum. I
will replace the rest of the ign parts next weekend. Thanks again for
the great responses.

Bill

 

My 1998 S 70 T 5 is doing the same thing. I have seen the recall and
this model is not covered buy the recall. What if anything can I try
to grt it back running "normal" again?