ok, after a million and one problems with my volvo (if i hadnt already spent 800 pounds on it i would have sold it by now) last night when i was parked for half an hour with engine running i noticed the revs started to dip below half a rev, did this a few times then the engine switched off. battery seemed fine. so i started the car and drove off, and every time the revs went to 2500rpm (exactly in any gear) the car would shuddder/jolt like the engine was going to cut off or the fuel supply was being strangled so to speak. this is the worst the cars been, so far ive had the usual hesitation but this, this was so bad that everytime it went to 2500 rev in wotever gear, it felt really rough, so much that my head would move back and forward (like when some one doesnt know how to drive and gives it too much gas then braking sharply? that kinda effect). i was embarrassed as everone one was looking like i had never driven a car before. my cars at the garage just now getting its springs replaced (both front and rear) time belt already replaced as well as a full 2 yr service 3 weeks ago. this morning on the way to the garage the car was absolutly fine, like it was brand new.

is this a sign of a faulty coil? having spent nearly a 1000 pounds (on the service inc new spark plugs, front brakes/discs, timing belt, and both front and rear springs) i have no money left to take it to a volvo dealer.
the car runs fine unless its btwn 2 and 3 thousand revs. (p.s is this also called missfiring)? engine management light doesnt come on (i wish it would so i can find out wot the problem really is)

 

Im about 95% sure the coil/coils are bad causing the Missfire.It is fine cold but once you get it hot it acts up.That is the typical sign of a bad coil/coils.

 

yeah thats correct! it was fine this morning and then i took it to the garage for ma front springs to be fitted, garage was only 20 mins away and the car was running fine. but after i got it back, it started jolting again, and when i was stuck in traffic, it just conked out( engine cut out), i restarted it and drove a bit forward and it started jolting and again the engine cut out, this happened a few times, so the only way i could stop this was by over revving and driving harshly , but you never know when the engine is gonna shut off completly.(pretty sure ive burnt the clutch by now). i parked up and started the engine again, it starts fine, no warning lights, but cuts out after 5-10 seconds! so i left it for an hour and drove off for 5 mins and then the same all over again!!! its like there no gas coming thru, but why does the engine cut off?

sorry to burden you with all this but this cars now dangerous. the rev needle tends to suddenly go up and down by 5 revs quid rapidly like its faulty, not moving smoothly at all. so you reckon its the coils? im gonna take it to volvo on my next day off, and in the mean time will just drive to work and back only.

 

They might want to check the fuel pressure as well.Or one of the coils has pretty much gone all the way.
One coils should run 2 cylinders.If the coil fails it will cut off 2 cylinders.
I would have them check the coils first.

 

Sounds like the same problem i have with it cutting out on idle but only when it is warm. The engine managment light came on so i took it the the volvo garage and they say i have a fuel pressure fault as it keeps loosing presure. they can put a new fuel pump on it but this might not fix it but they say i need to change this to eliminate this but it ight not be this and it only costs me £411 + VAT. so pretty cheap to change just in the offchance it might be that. they probable would have hit me with the fact that it needs to be de coked but the same garrage did that already 6 months ago under warenty. haha. as you said the car runs fine untill you are sitting still and let the revs drop.

i am looking for more advice before i need to fork out so much money on a whim.

the volvo garrage also said i would need to keep the bit even if it was not this.

great.

My car is the GDI engine not sure what yours is.

hope this helps

regards
Lee

 

yeah its the 1.8 gdi engine. ive done some research and its a known problem with mitsubuishi gdi engines. some one on another forum knows a guy who works for mitsubuishi, apparantly these engines were designed for the japanese market not the european market. anyway, im looking for a garage that can do the decoke for less than a £1000.

this is wot one of the guys said.

"If it needs a head off decoke then it must have been running very badly adjusted on the fuel side to build up such an amount of ****. I'd maybe find a independant garage as it's only really a matter of whipping the head off and cleaning the carbon off with a wire brush and reassembling so you'd certainly cut the labour bill probably in half. You could try an injector cleaner, I've even heard that a good fine mist of water sprayed into the throttle body can help as the steam loosens the carbon (do this with extreme caution, too much and you'll hydraulic lock the engine and break something expensive) but if it's this bad then only a manual decoke will probably do the trick. Parts you'd need would be a head set (this contains all the gaskets and seals that you'd need) and maybe things like new head bolts/studs if they are the kind that stretch when tightened. This really will take only a little more time than changing a head gasket."

then went on to say

"Carbon build-up is generally as a result of over fuelling and incomplete ignition, this could also be related to a coil pack problem. A lot of older cars 70's and earlier needed regular decokes and as such used to be a common problem, much much less so today as today computer controlled engines don't suffer from it. Carbon build up can also result in the engine running on when you turn it off as the carbon glows red hot like a lump of coal and ignites fuel without the need for a spark."

probably doesnt help either of us as were gonna have to spend lots of money to fix it, me being more out of pocket than you as youve already had the decoke!!!

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