V40 1999 P - Lack of power - Spark Plugs?

russell37uk · Post by **russell37uk** » 23 Nov 2009, 06:53

Hi all,

I have a Volvo V40 manual gearbox(P reg- 1999 i think) approx 168,000 miles, and I have this problem with a lack of power.

When the car is in neutral and idling the engine is fine, rev the engine and its not too bad but has a little lack of power like what you get on a really cold start but not too bad, the problem is when you put it into gear, the lack of power makes it hard to pull out unless you really rev the engine for the extra power.
This problem is in all gears when accellerating no matter what the speed of travel, and it does of course interfere with driving when it comes to going up hills as you lose 'driving' power even though the revs show otherwise.

The lack of power is more like having a cold engine (eg the phrase 'not firing on all cylinders'), and not the lack of power you'd get if the gear was too high for the speed of travel.

Also I have this problem wether the engine is hot or cold.

Does anyone have an idea of what the problem might be?
Spark plugs, Fuel pump, fuel filter etc?

I did at first think it was the gearbox playing up, but as it has the power loss (as in a cold start) when revving in neutral I have ruled that out.

Any advice you can give me would be helpful.

Many Thanks

russell37uk · Post by **russell37uk** » 23 Nov 2009, 13:22

I forgot to add that at about 3000 revs the problem goes (and I get a sudden burst of speed), but its back again as soon as the revs drop to about 2000 revs

Post by **billofdurham** » 24 Nov 2009, 11:48

Welcome to Matthew's Volvo Site.

Is the Check Engine Light (CEL) illuminated? Have you checked for fault codes that may be stored?

Some things to check are:
Defective airflow sensor.
Damaged ignition wires.
Blocked air cleaner/intake.
Low fuel pressure.
Blocked exhaust, especially the catalytic converter.
Fuel injectors.
Coolant temperature sensor.
Engine speed sensor.
Throttle switch and connector.

Bill.

russell37uk · Post by **russell37uk** » 24 Nov 2009, 13:34

Hi Bill,

Thanks for the welcome and your reply.

I do not have any warning lights showing, the power loss could be describes as a 'stutter' i suppose as there is no backfiring connected to the problem.

I have had the car for about 3 months, but i do know at around the time of the last mot (march 2009) a new catalytic converter was fitted.
The problem I have got though started about a week-10 days ago and everything was fine until then.

This problem is the 'stutter' that you'd get when starting on a cold morning before the engine has warmed up, but this is happening wether the engine is cold or hot.
Also this problem stops at approx 3000 revs (in any gear), but returns when the revs drop to approx 2000 revs - although you wouldn't notice unless you was going up hill.

Many thanks again for your reply and tips.

NB: I have also checked the air cleaner/filter which is clean (but this was new when I got the car.)

Post by **billofdurham** » 24 Nov 2009, 15:27

Not all fault codes will set the CEL so find a friendly local garage and ask them to run a diagnostic with a code reader.

The new cat could still be a cause of trouble depending on how it was handled by the fitter or, more likely to maltreat it, the delivery person. I have seen new cats dropped onto the shop floor on delivery and they weren't fit to be used. Again, your friendly garage can test this.

If these steps don't sort it out then you will have to go through the check list. Start with the easy stuff like the ignition wires, condition and possible bad connections. The airflow sensor may be dirty, although they are supposed to be self cleaning. You can buy an aerosol of special cleaner and give it a quick squirt. Check the connections to all of the sensors. Disconnect them and look at the pins to make sure there is no dirt or oxidation which would give a bad connection.

Bill.

russell37uk · Post by **russell37uk** » 24 Nov 2009, 16:10

Thanks for the tips bill, i'll give them a try and see what happens.

The diagnostics reader test - would any local garage be able to do this or a volvo garage?

Just saves me a few phone calls

Post by **billofdurham** » 25 Nov 2009, 12:27

Steer clear of the dealer as you will need a mortgage.

Most garages have a scanner now but the likes of Halfords, Charlie Browns and other national service chains definitely have them. Also check in Yellow pages for an auto-electrician. They will have the right kit.

Bill.