I posted this on Newbies, but got no replies, so i hoped there might be more people to see the post here,
Been a few years since I was on here. In the past I had a 244, a 960 an S80, 1999 V70, a 2004 V70 and after a few years have gone by I have purchased another V70, (2001) 2.4, litre petrol 198000 on the clock.
The car has had the same owner from new until September 2019, The car was regularly serviced, any problem was quickly cured (by the look of all the receipts and work orders I received with the car), and was looked after by a Volvo dealership. It was then given/purchased by a friend of the family and left sorned on his drive until I purchased her last month.
I can't fathom out the problems she has though.
(Problem 1)
Keeps missing while sitting at around 30mph, I've put new plugs in, checked the coil packs by starting the car up and removing the connector to each coil pack, all seem to be working fine. I've filled up the petrol tank added injector cleaner and driven around until the tank is back down to quarter full, but it still has the same problem.
(Problem 2)
Thumping from underneath of the car. I have had the car in for an MOT and asked the inspector to take special note of anything that might be causing these thumps.
To my surprise, the car passed it's MOT and the inspector said everything was as it should be, nothing worn or loose.
None of my previous V70's have had either of these problems.
UPDATE
I took the car back to the garage and the mechanic drove the car , verified the noises, then had the car back up on the lift, 2 mechanics checked and re checked every moving part with no result.
Just can't find anything that could be the cause of the noise
Any advice will be appreciated
Thanks
JodyBeen a few years since I was on here. In the past I had a 244, a 960 an S80, 1999 V70, a 2004 V70 and after a few years have gone by I have purchased another V70, (2001) 2.4, litre petrol 198000 on the clock.
The car has had the same owner from new until September 2019, The car was regularly serviced, any problem was quickly cured (by the look of all the receipts and work orders I received with the car), and was looked after by a Volvo dealership. It was then given/purchased by a friend of the family and left sorned on his drive until I purchased her last month.
I can't fathom out the problems she has though.
(Problem 1)
Keeps missing while sitting at around 30mph, I've put new plugs in, checked the coil packs by starting the car up and removing the connector to each coil pack, all seem to be working fine. I've filled up the petrol tank added injector cleaner and driven around until the tank is back down to quarter full, but it still has the same problem.
(Problem 2)
Thumping from underneath of the car. I have had the car in for an MOT and asked the inspector to take special note of anything that might be causing these thumps.
To my surprise, the car passed it's MOT and the inspector said everything was as it should be, nothing worn or loose.
None of my previous V70's have had either of these problems.
Any advice will be appreciated
Thanks
JodyBeen a few years since I was on here. In the past I had a 244, a 960 an S80, 1999 V70, a 2004 V70 and after a few years have gone by I have purchased another V70, (2001) 2.4, litre petrol 198000 on the clock.
The car has had the same owner from new until September 2019, The car was regularly serviced, any problem was quickly cured (by the look of all the receipts and work orders I received with the car), and was looked after by a Volvo dealership. It was then given/purchased by a friend of the family and left sorned on his drive until I purchased her last month.
I can't fathom out the problems she has though.
(Problem 1)
Keeps missing while sitting at around 30mph, I've put new plugs in, checked the coil packs by starting the car up and removing the connector to each coil pack, all seem to be working fine. I've filled up the petrol tank added injector cleaner and driven around until the tank is back down to quarter full, but it still has the same problem.
(Problem 2)
Thumping from underneath of the car. I have had the car in for an MOT and asked the inspector to take special note of anything that might be causing these thumps.
To my surprise, the car passed it's MOT and the inspector said everything was as it should be, nothing worn or loose.
None of my previous V70's have had either of these problems.
Any advice will be appreciated
Thanks
Jody

 

A key for diagnosis is to determine when, under what specific circumstances, the thumping sound occurs. The most likely problem areas, IMO, are the suspension, drive train between the transmission and the rear axle, and the engine mounts. Due to the car's age, my guess is that some rubber-based seal or cushioning part is rotted and defective, which allows for a metal-to-metal contact.

You mentioned that the car was "regularly serviced" and "any problem was quickly cured". To me, there's three levels of service: (a) routine changing of fluids and common wear parts, (b) fixing problems when they occur and (c) preventive maintenance/replacement of common age-based wear parts, where needed. My guess, since the prior owner was dependent on high-cost dealer repairs, was that the last level of service may not have occurred, which is understandable.

Regarding your (first) engine performance issue, before replacing parts, my advice would be to scan for codes, and go from there. Investment in a scanning tool can pay for itself. Since you may already have access to the prior owner's repair bills, I'd also advise creating a spreadsheet to list the mileage, along with the associated repair issue and remedy enacted. In reviewing the prior repair bills, perhaps one of these may show that your engine performance issue occurred in the past, and was "fixed" by the dealer (sometimes replacement parts can be defective ... or the repair person could have replaced an part that was not the cause of the concern).

Some questions to ask about when the thumping sound is generated ....

While driving on irregular surfaces? (suspension?)
While changing gears? (drive train?)
Once a particular speed or gear is reached? (drive train?)
While car is in "park" and the engine is rev'd, does the thump occur? (motor mounts?)
Do you feel vibration in the steering wheel or gas pedal when the thumping sound occurs? (various sources)
Does your V70 have Haldex AWD? If yes, was it serviced (fluid change, pump screen cleaned, etc)?

Concerning the engine performance issue, my advise is to scan for codes prior to replacing parts.

PS: I am not a mechanic, just a person, to a certain extent, who has been-there-done-that.

PPS: One last suggestion. I would urge you to go the the Swedespeed forum (https://forums.swedespeed.com/). There, you will be certain to find enthusiasts would may have experienced similar issues and/or can offer more specific DIY advise. I've also found that the people at this site are far more proactive at communicating and more helpful.

 

Update
Sorted the thumping. It was the nearside front strut rubber mount.
Still unsolved is the engine problem.
Will hold back (as if lack of fuel), then pulls away.
If I drive it hard in any gear, the car picks up speed quickly, then go up a gear it holds back (as if lack of fuel) then pulls away
There are no faults showing, (Bought an OBD2 scanner)
Went out 1st thing this morning and checked the spark plugs. Number 1 and number 4 plugs were wet!
The car starts up 1st turn of the key every time
The other odd thing is when I take my foot off the accelerator to change gear, the revs will go up (as if I were engaging clutch before removing my foot off the accelerator), and then falling back again, but it doesn't do this while parked up and in neutral.
Has anyone else experienced this, and if so did you get the problem sorted?