Power and Speed Diagnosis

Dr_Colossus

Hi
I've a 01 Volvo S40 1.8i (GDI type petrol engine) with 110k miles on the clock. I have the car about 3 months and usually it's running fine but somewhat lacking in power and take off for a 1.8 petrol.

The problem though is that recently it's really lacking in power, for instance I made a return trip to Cork from Dublin two weeks ago and while on the motor way with cruise control set at 110km/h every so often it would drop in speed and really struggle up some of the hills. I'd have the shoe to the floor and it would struggle to get above 95km/h, dropping a gear didn't make much difference either. The revs weren't any higher than the normal 3,000 for 110km/h so I don't think there's any problem with the clutch. After a while the speed and power would recover but overall very inconsistent. Also on that trip it guzzled petrol with the mpg reading rarely getting above 11.1. I've done other longer motor way trips to Galway and Limerick and on those the power and mpg were decent.

I'm guessing that the engine may only be firing on 3 cylinders alot of the time or else the timing is off. Does this sound like a reasonable assumption, I'm no car or engine expert? For a bit of back ground the garage I bought the car off was supposed to do a full service before the sale but when I checked the oil and air filter it was obvious it wasn't done. Anyway after some agro with the garage they eventually agreed to take it in for the service and I left it with them last night. I told them the plugs would also need replacing since it wasn't firing on all cylinders and overall lacking in power and severely so when occasionally driving at speed on the motorway.

Any other ideas as to what the problem could be or advise in general? Don't want to be fobbed off with blatant lies from the sales man again when I go to collect during the week.
Thanks

Dr_Colossus

Bit of a bump, anyone have any ideas or recommendations on the above?

langdang

Dr_Colossus wrote: »

the garage I bought the car off was supposed to do a full service before the sale but when I checked the oil and air filter it was obvious it wasn't done.

Fairly common unfortunately. Try to get it on paper what they've done. I'd also be wary of the actual mileage after buying from one of these outfits that don't even change the oil after promising to service it... If you have a garage you trust take it there afterwards for a proper once over.

Does it "tick" loudly at idle, with the speed of the "ticking" increasing with engine speed? The valves on this engine can get coked up because of the GDI.

DublinDilbert

Could be any number of things, although cause it seems so low on power should be a little easier to spot. Will need the codes read, if that shows up nothing time to look at the various sensors, coils etc....

Dr_Colossus

langdang wrote: »

Does it "tick" loudly at idle, with the speed of the "ticking" increasing with engine speed? The valves on this engine can get coked up because of the GDI.

Thanks, no there's no ticking at all from it, it's fairly quite overall with no obvious sounds either while idling or at speed. One thing though is that occasionally while cold the revs while idling with drop to maybe 300 or 400 and it'll start to chug but I think that's more to do with the idle control valve needing a cleaning. Will be going through it after the service cleaning the trottle valve and idle control value anyway.

Dr_Colossus

Got the car back from the garage after the supposed service and checked the plugs, pics attached. They don't look obviously new to me and the gaping on one of them seems way off, any estimate as to how many miles these plugs have done? Also what would cause the gaping to be different on one.

Anyway hoping that the plugs may be cause of some of the power issues, it's the first step anyway. So can anyone advise what are the correct plugs for a Volvo S40 GDI 1.8 and what is the correct gaping. The existing ones are NGK R with code BKRGE 11 but not sure about the gaping.

VinnyTGM

That plug on the left is damaged, are these the new plugs they put in, if so this isn't on.

I'm hoping that they dropped it on the floor or something, and that it didn't get damaged in the engine.

Get a compression test done.
It will highlight if your engine is down on power. ie headgasket, piston rings etc. If your headgasket is gone check to see if there is oil in the coolant, or if there is coolant coming out of the exhaust.

Although it could be the plug not firing properly due to it being damaged, basically making one of your cylinders redundant, it could explain why it feels down on power.


This garage sounds like their cowboys.

Dr_Colossus

Yea the garage/sales man I bought the car from is just a liar and a complete gobsh*te. I wasn't going letting him off with the service though since it was part of the deal and he never bothered to do it hoping I wouldn't chase him for it. I told him to put new plugs in it as part of the service since it wasn't running correctly and he said he'd check it out but obviously never even took out the plugs to inspect them. If he'd told him he wouldn't cover the plugs as part of a full service and he'd have to charge me €40 extra or whatever I'd have alot more respect for him than all these lies.

Esel

Ianam, but those plugs look fairly black to me - or is it just the lighting?

Did you take any shots of the electrodes straight on?