Volvo Community Forum. The Forums of the Volvo Owners Club

Forum Rules Volvo Owners Club About VOC Volvo Gallery Links Volvo History Volvo Press
Go Back   Volvo Owners Club Forum > "Technical Topics" > 850 / S70 & V70 '96-'99 / C70 '97-'05 General

Notices

850 / S70 & V70 '96-'99 / C70 '97-'05 General Forum for the 850 and P80-platform 70-series models

Information
  • VOC Members: There is no login facility using your VOC membership number or the details from page 3 of the club magazine. You need to register in the normal way
  • AOL Customers: Make sure you check the 'Remember me' check box otherwise the AOL system may log you out during the session. This is a known issue with AOL.
  • AOL, Yahoo and Plus.net users. Forum owners such as us are finding that AOL, Yahoo and Plus.net are blocking a lot of email generated from forums. This may mean your registration activation and other emails will not get to you, or they may appear in your spam mailbox

Thread Informations

lack of power

Views : 1890

Replies : 26

Users Viewing This Thread :  

Reply
 
Thread Tools Display Modes
Old Apr 17th, 2012, 19:02   #1
marc850
New Member
 

Last Online: Jun 11th, 2013 18:33
Join Date: Apr 2012
Location: gateshead tyne & wear
Smile lack of power

Hi all,
i'm new today to the voc forum, my name is marc and i would appreiciate some help or advice if possiple please. i have recently purchased an 850 estate the 2.5 10v, which seems to be lacking in acceleration and power. i have changed all the relevant service parts, oil filter, air filter, fuel filter, spark plugs but the car still seems flat. i have never owned an 850 before but have had a v40 2.0 which was rapid compared to this. is this common in the 850 to be honest i was expecting a bit more oomph as i have desired an 850 for quite some time. any advice?
thanks.

Last edited by marc850; Apr 17th, 2012 at 20:01.
marc850 is offline   Reply With Quote
Old Apr 17th, 2012, 21:17   #2
capt jack
VOC Member
 

Last Online: Today 21:31
Join Date: Jun 2006
Location: Selby, North Yorkshire
Default

Well the B5252S engine isn't the quickest out of the blocks, but it should be fairly lively.

Is the car manual or auto?

Check that the handbrake is releasing OK. Also, have a look at the temperature gauge. It should reach the midpoint quite quickly (within a mile or two from cold) and then sit there, regardless of the driving conditions. If not your thermostat is shot, and this can certainly affect performance. Just last week I found out the hard way that a poor connection between the temp sensor and the wiring loom (the connector is hidden behind the power steering tank) was enough to make mine feel a bit stodgy until the engine started to warm up.

If the plug leads, rotor and distributor cap are tired that'll affect things. I've found with my car that these need to be changed every 100k miles or so. It is possible simply to clean up the dissy cap contacts and the tip of the rotor, but if the ones on there have done a big mileage then it's as easy just to fit new.

Make sure too that the tyres are correctly inflated!

Hope that gives a few pointers.

Cheers

Jack
capt jack is online now   Reply With Quote
The Following User Says Thank You to capt jack For This Useful Post:
Old Apr 17th, 2012, 21:41   #3
catflem
Master Member
 

Last Online: Oct 20th, 2023 13:15
Join Date: Jun 2006
Location: Expat in NW France
Default

Quote:
Originally Posted by capt jack View Post

If the plug leads, rotor and distributor cap are tired that'll affect things. I've found with my car that these need to be changed every 100k miles or so.
Bloody hell, they don't make em like they used to. I remember the days you could get 4 million miles out of a Volvo between spark plug changes :-).

Capt Jack has nailed it I think.

The only other thing I can think of to check out is the MAF sensor.
__________________
Quick, someone flog me a V70 before I jump ship again
catflem is offline   Reply With Quote
The Following User Says Thank You to catflem For This Useful Post:
Old Apr 18th, 2012, 01:43   #4
marc850
New Member
 

Last Online: Jun 11th, 2013 18:33
Join Date: Apr 2012
Location: gateshead tyne & wear
Thumbs up

Thanks guys i will certinately have a look at the distributor cap and leads as this seems like an easy fix, what about the maf sensor tho' where would i find that? and what sort of difference would it make (what does it do should i ask ?) should the 850 2.5 10v be quite keen on the throttle and how does it compare to the other models like the 20v or the GLT etc? i wasn't expecting a rocket, but a little more give without having to hammer down the accelerator pedal which doesn't do my mpg any good i've noticed.

Sorry forgot to mention the car is manual, not keen on autos as i know they can be a little less responsive.

Last edited by marc850; Apr 18th, 2012 at 01:47. Reason: forgot to ad
marc850 is offline   Reply With Quote
Old Apr 18th, 2012, 18:39   #5
marc850
New Member
 

Last Online: Jun 11th, 2013 18:33
Join Date: Apr 2012
Location: gateshead tyne & wear
Default

Quote:
Originally Posted by catflem View Post
Bloody hell, they don't make em like they used to. I remember the days you could get 4 million miles out of a Volvo between spark plug changes :-).

Capt Jack has nailed it I think.

The only other thing I can think of to check out is the MAF sensor.
Evening! picking up from yesterday you mentioned the MAF sensor, what does this do and where would i find it? also is it a costly part?

Cheers.
marc850 is offline   Reply With Quote
Old Apr 18th, 2012, 19:32   #6
stuv7010v
Junior Member
 

Last Online: Sep 9th, 2012 20:47
Join Date: Mar 2012
Location: aylesbury
Default

I second capt jack, I had exact same probs on my v70 10v, after changing the obvious turned my attention to thermostat and ect sensor.
The car was juddering very badly from cold and had slight misfire under load when warm and felt "restricted"
I replaced both thermostat and ect and have noticed a difference immediately, like a new car!
stuv7010v is offline   Reply With Quote
The Following User Says Thank You to stuv7010v For This Useful Post:
Old Apr 18th, 2012, 21:38   #7
catflem
Master Member
 

Last Online: Oct 20th, 2023 13:15
Join Date: Jun 2006
Location: Expat in NW France
Default

Quote:
Originally Posted by marc850 View Post
Evening! picking up from yesterday you mentioned the MAF sensor, what does this do and where would i find it? also is it a costly part?

Cheers.
Oops, I didn't read your engine spec properly......... I don't think the 10V has a MAF.
__________________
Quick, someone flog me a V70 before I jump ship again
catflem is offline   Reply With Quote
The Following User Says Thank You to catflem For This Useful Post:
Old Apr 18th, 2012, 21:52   #8
capt jack
VOC Member
 

Last Online: Today 21:31
Join Date: Jun 2006
Location: Selby, North Yorkshire
Default

Not a MAF but it will have a MAP sensor, tucked just above the radiator with a couple of electrical connection and a vacuum pipe. There'll also be an air inlet temp sensor in the inlet air trunking between the air filter box and the throttle body.

The ECU has to work out how much air is coming into the engine. On a car with a MAF sesnor system, it does this by measuring air flow MAF = mass air flow. On a car with a MAP sensor it does this by measuring the the Manifold Absolute Pressure and then using information about the air temperature to calculate the mass of air. This in turn is used to work out how much petrol to squirt through for the calculated amount of air. Sounds complicated but it's actually quite straightforward and generally reliable. If something's amiss however, you'll get problems of either under- or over-fuelling and the engine will misbehave.

Faults should throw a code and light up the engine management light.

I reckon a Haynes book would be a good investment to help you find your way around the engine bay.

Cheers

Jack

One last thing - make sure the throttle cable can move freely. They do rust up once the plastic sleeving starts to deteriorate. An easy fix to replace - but if it is a bit grotty try running some oil down the cable first!

Jack

Last edited by capt jack; Apr 18th, 2012 at 21:55.
capt jack is online now   Reply With Quote
The Following User Says Thank You to capt jack For This Useful Post:
Old Apr 23rd, 2012, 20:28   #9
Nicks 850 broke!
Member
 

Last Online: Oct 13th, 2013 19:14
Join Date: Jan 2010
Location: Houston
Default

Hi Marc

In the last 3 years I've gone 2.3 T5 to 2.0 20v and then to 2.5 10v - the latter two are nominally same 140bhp output but 2.5 feels much more relaxed in its power delivery - I'd need to check the books but I think that not only the T5 but also the 2.5 have higher gearing than 2.0 - going from T5 to 2.0 I'd noticed I had to work the 2.0 harder (no s**t sherlock!) but that actually it was lower geared so revved higher at all speeds and not actually desperately good on mpg - the 2.5 is far more relaxed and I am seeing much better economy from it than the 2.0. I still miss my turbo though but have another about-to-be-17-year-old to put L plates on for this year and another one in 2014 so it's no turbos for the present.

Nick
__________________
Current Volvo (2012- ) - 1996 "P" Silver Volvo 855 2.5S 10v Manual Estate
Previous Volvo (2010-2012) - 1996 "N" Met Purple Volvo 855 2.0S 20v Manual Estate
Previous Volvo (1999-2010) - 1995 "M" faded red Volvo 855 T5 Estate (black ice victim)
Nicks 850 broke! is offline   Reply With Quote
The Following User Says Thank You to Nicks 850 broke! For This Useful Post:
Old Apr 26th, 2012, 17:56   #10
marc850
New Member
 

Last Online: Jun 11th, 2013 18:33
Join Date: Apr 2012
Location: gateshead tyne & wear
Thumbs up

Hi all!,

Sorry chaps but i've been working away and never had a chance to thank you properly for your very imformative comments, i've took every thing into consideration and it's nice to know that there are people out there whom really know there stuff!

One thing i didn't mention tho and i don't know if it will play a factor or not, but the service light is illuminated and was when i purchased the car. would this effect the cars performance? if so does anybody know how i can turn it off with out going down the obvious route of garages, some sort of sequence maybe?

Cheers.
marc850 is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +1. The time now is 21:31.


Powered by vBulletin
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.