IPD sale XeMODeX - Experts in Volvo Electronics Free shipping all USA - Experts in Brakes
Did you know? 🤔
Logged in users can get email notification of topic replies Log in or register (free).
Amazon Link Buy anything with this and it helps MVS!

96 850 Turbo Rough idle and die Topic is solved

Help, Advice and DIY Tutorials on Volvo's extremely popular car line -- Volvo's 1990s "bread and butter" cars -- powered by the ubiquitous and durable Volvo inline 5-cylinder engine.

1992 - 1997 850, 850 R, 850 T5-R, 850 T5, 850 GLT
1997 - 2000 S70, S70 AWD
1997 - 2000 V70, V70 AWD
1997 - 2000 V70-XC
1997 - 2004 C70

volkans80
Posts: 26
Joined: Thu Jun 06, 2013 11:37 am
Year and Model: 850 T5, 1996
Location: Turkey
Has thanked: 0
Been thanked: 0
Turkey
volkans80

96 850 Turbo Rough idle and die

Post by volkans80 » Fri Sep 09, 2016 4:29 am

Hi,

My 850 (Motronic 4.3) started to random rough idle and sometimes dies. Spark plugs (bosch), plug wires (bougicord), distributor & rotor (bosch), o2 sensor (bosch), PCV system, turbo's small air hoses and vacuum hoses are new. First times there is 232 231 435 and replaced o2 sensor error codes gone but problem not changed. I doubt crankshaft sensor because one year ago car stopped running and i cleaned crankshaft sensor. Also there is strange behaviour. Sometimes when i push gas pedal it starts accelerating and stops, rpm downs a bit and then starts accelerating then repeat same thing.

Is crankshaft sensor can immediately cuts firing and lets it continue?
Is crankshaft sensor can effect idling?

Thanks,

Sommerfeldt
Posts: 1120
Joined: Tue Jul 29, 2008 1:25 pm
Year and Model: 1996 850 T5
Location: Oslo Area, Norway
Has thanked: 52 times
Been thanked: 31 times
Norway
Sommerfeldt

Re: 96 850 Turbo Rough idle and die  Topic is solved

Post by Sommerfeldt » Fri Sep 09, 2016 5:17 am

The most probable possibility that's missing from your list is the MAF. Unplug it, start the car and see if the car idles / runs better without it. If it does, you've found your problem.

- S
'96 855 T5, R bumper and spoiler, Koni Yellows & blue H&R springs all 'round.

volkans80
Posts: 26
Joined: Thu Jun 06, 2013 11:37 am
Year and Model: 850 T5, 1996
Location: Turkey
Has thanked: 0
Been thanked: 0
Turkey
volkans80

Re: 96 850 Turbo Rough idle and die

Post by volkans80 » Fri Sep 09, 2016 6:10 am

But mostly the car is running good. For example today i drive the car about one hour everything is ok but when i parking it die 6-7 times. 20 minute later i drive the car again 30 minute everything is ok. Two hour later i drive the car 30 minute everyting is ok. There is not a rough idle today but it died 6-7 times while parking.

Do you recommend unplug MAF and drive the car 1-2 days?

Sommerfeldt
Posts: 1120
Joined: Tue Jul 29, 2008 1:25 pm
Year and Model: 1996 850 T5
Location: Oslo Area, Norway
Has thanked: 52 times
Been thanked: 31 times
Norway
Sommerfeldt

Re: 96 850 Turbo Rough idle and die

Post by Sommerfeldt » Fri Sep 09, 2016 6:30 am

No, don't do that. When you're idling rough, stop the car. Unplug MAF. Start car. See if problem goes away/gets better. If it does, get a new MAF.

- S
'96 855 T5, R bumper and spoiler, Koni Yellows & blue H&R springs all 'round.

volkans80
Posts: 26
Joined: Thu Jun 06, 2013 11:37 am
Year and Model: 850 T5, 1996
Location: Turkey
Has thanked: 0
Been thanked: 0
Turkey
volkans80

Re: 96 850 Turbo Rough idle and die

Post by volkans80 » Fri Sep 09, 2016 6:35 am

Ok I will try this. Thank you.

User avatar
rspi
Posts: 7248
Joined: Sat Nov 05, 2011 10:40 am
Year and Model: 850 T-5R Wagon
Location: Albuquerque, NM
Has thanked: 19 times
Been thanked: 41 times
United States of America
rspi

Re: 96 850 Turbo Rough idle and die

Post by rspi » Fri Sep 09, 2016 6:45 am

Is there a check engine light? What are the P codes?
'95 855 T-5R M, Panther - 22/28 mpg
'98 S70 GLT, Lil' Red 25/32 mpg
--------------------
Volvo's of past: '87 740 GLE, '79 262C Bertone, '78 264, 960's, '98 S70 GLT, '95 850 T-5R YellowVolvo Repair Videos

volkans80
Posts: 26
Joined: Thu Jun 06, 2013 11:37 am
Year and Model: 850 T5, 1996
Location: Turkey
Has thanked: 0
Been thanked: 0
Turkey
volkans80

Re: 96 850 Turbo Rough idle and die

Post by volkans80 » Fri Sep 09, 2016 7:23 am

I don't know P codes but first times there are 232 231 435 dtc codes. When i changed o2 sensor all gone.

I don't know if it is related but yesterday i checked wastegate rod by hand and I just read codes again and now there is only 414

User avatar
misha
Posts: 4200
Joined: Sun Dec 07, 2008 4:09 pm
Year and Model: '97 850 2.5 20v
Location: Serbia
Has thanked: 54 times
Been thanked: 117 times
Serbia
misha

Re: 96 850 Turbo Rough idle and die

Post by misha » Fri Sep 09, 2016 7:30 am

Since you have intermittent problem and it points towards the Maf...i would try a zip tie method on Maf's connector.That's a common fault on these cars.

Did you reset codes and ecu after o2 sensor replacement?
'97 850 2.5 20v / fully equipped / Motronic 4.4 from the factory / upgraded with S,V,C,XC70 instrument cluster / polar white wagon
'91 Citroen XM 2.0 SI /fully equipped/mandarine red metallic
History of Volvos in the family:
'71 144 S
'73 144 De Luxe
'78 244 DL
'78 244 DL
'79 244 GLE
'85 340 GLS

volkans80
Posts: 26
Joined: Thu Jun 06, 2013 11:37 am
Year and Model: 850 T5, 1996
Location: Turkey
Has thanked: 0
Been thanked: 0
Turkey
volkans80

Re: 96 850 Turbo Rough idle and die

Post by volkans80 » Fri Sep 09, 2016 8:03 am

Yes maybe MAF's connector loose. I will try zip tie.

I cleaned codes but not ecu. How can i reset ecu? If i disconnect battery, ecu resets?

User avatar
misha
Posts: 4200
Joined: Sun Dec 07, 2008 4:09 pm
Year and Model: '97 850 2.5 20v
Location: Serbia
Has thanked: 54 times
Been thanked: 117 times
Serbia
misha

Re: 96 850 Turbo Rough idle and die

Post by misha » Fri Sep 09, 2016 8:33 am

After you zip tie Maf's connector,remove battery cables for around 15 min in order to reset ecu's fuel trim.

Maf connector is always safely secured with it's clip connector.The problem are the wires which connects to connector's pins.
'97 850 2.5 20v / fully equipped / Motronic 4.4 from the factory / upgraded with S,V,C,XC70 instrument cluster / polar white wagon
'91 Citroen XM 2.0 SI /fully equipped/mandarine red metallic
History of Volvos in the family:
'71 144 S
'73 144 De Luxe
'78 244 DL
'78 244 DL
'79 244 GLE
'85 340 GLS

Post Reply
  • Similar Topics
    Replies
    Views
    Last post