440 Misfire

Hi everyone,

Bought my second Volvo a few weeks ago (first was a 460 which I unfortunately wrote off, best car I ever had too), it's a 440 SE 2.0i on an N-plate, with 90K on the clock.

Never noticed the misfire when I bought it, however a week or so later it seemed to start. Mainly at tickover/low revs (sub 2,500ish) but it could be quite severe. Took it to a garage (the exhaust was blowing too, but it was only £10 to get it welded). He said he didn't know what was causing it, but it didn't look like it's been serviced for some time (last service I'm aware of was about 55K), and recommended a new distributor cap + rotor arm.

I did that - no change. So I bought new plugs too - again, no change. Replaced HT leads, this seemed to almost cure it, but there was still a bit of a misfire present. Next thing I tried was putting redex in the tank when I filled up - nightmare!

The misfire now seems far worse than ever, the car sometimes judders like crazy and won't pull anywhere near like it should the majority of the time. I've only done about 30 miles since, and it did seem to improve considerably for the last few. Is this normal?

Anybody got any other suggestions?

[bob13]

Hi Sheffield.
Sounds like a fuel problem, if the problem has got worse since you put in red x it may have just loosened all the muck in the tank, pump, pipes etc. I would try the fuel fillter first but get a friend to help, did mine not so long ago and i took two of use as the connectors were rusted on good and proper. All the best BOB

Interested to read your reply Bob. I'm just about to change my filter and I'm wondering why it needs four hands. Is it to stop the unit twisting while one of you tries to undo a connector? Any tips would be much appreciated. Have to say I too thought the misfire sounds like fuel starvation or contamination. Cheers Sarumboy

[bob13]

Originally Posted by sarumboy

Interested to read your reply Bob. I'm just about to change my filter and I'm wondering why it needs four hands. Is it to stop the unit twisting while one of you tries to undo a connector? Any tips would be much appreciated. Have to say I too thought the misfire sounds like fuel starvation or contamination. Cheers Sarumboy

The fuel filter is under the car (1991, 440) which made it hard to get at on a jack, you stop the filter from turn by putting a spanner on the filter itself (18 or 19mm from memory). And then a spanner on the fuel conector. When i tried myself i could not get the power on both spanners to release the connector so with two of you, one can push one spanner and pull the other. My filter may not be the norm however. One other thing to watch out for, the fuel pipe is supposed to turn so when you undo it from one side of the filler the pipe wont twist. Not in my case the pipe would not move (to much rust road dirt etc) and we ended up cutting the pipe, cleaning the connector so it would turn and reconnecting it, a bit of wd 40 before hand may help.
Have fun Bob.

[Alec Dawe]

Does the 440 have such a thing as the old fashioned Ignition Coil?
I had an untracable misfire years ago which finally turned out to be an invisible, hairline crack in the INSIDE of the coil, caused by a slight bump, which had discomknockerated the insides.
New coil instant cure.

[740Estate]

discomknockerated

I have just sprayed my keyboard with Coffee!! Laugh? Im in tears

[Alec Dawe]

Originally Posted by 740Estate

I have just sprayed my keyboard with Coffee!! Laugh? Im in tears

Sorry! Its an old 'Family' word!

Thanks a million for the tips Bob, thats the sort of information you can only get by experience. My task is going to be easier as a result. Cheers, Sarumboy
PS This is turning out to be quite an entertaining thread!!

[Daniel M]

I had misfire on my 480. Check the sparkplugs are in at the correct angle-if they aren't and they've been cross threaded then the plug won't be in the correct place so won't spark correctly.

Also, another thing that might affect it is the king HT lead (from the coil to the centre of the dizzy cap). Sometimes it doesn't quite connect properly so causing misfire. This is often overlooked when changing leads. Also, have you tried doing the diagnostic? If you haven't, try this link and it could help you find your problem. The car's quite clever, so will identify where the problem is.

http://www.troublecodes.net/Volvo/

I'm not sure that a fuel starvation problem would cause mis-fire. I think your problem is down to an electrical fault. Also, check the wire going to your crankshaft sensor. I don't think it could be this, but a broken wire or faulty sensor could cause similar problems.

Keep us posted and let us know when you solve it.

OK, bit of an update:

First, I am by no means what you would call a competent mechanic, the bits I have done already are about my limit. I don't feel altogether comfortable changing the fuel filter, simply because I don't fancy working around fuel spillages (no matter how slight).

But as I always get the timing belt changed when I buy ANY car (irrespective of mileage, service history etc) I booked it in at a garage ("volvo specialist", they claim - not a dealership though) for this, and told them what's been happenning.

Now this is where I get a bit scared - the mechanic checked the coolant level, and noticed it was low. I told him that I had been topping it up a little more regularly than normal, but had assumed this was mainly due to the hot weather spells we'd had (honestly, we've had SOME).

Garage will be doing a compression test as well as a diagnostic as they think it MAY be the head gasket that's gone. Now I'm not sure if this is the garage trying to make some money out of me: I haven't heard any whistling, the temperature gauge hasn't gone excessively high (obviously a bit high in traffic, but nothing I'm overly concerned about), and the coolant looks "clear" - there doesn't appear to be any mixing. In addition, I haven't noticed it using any oil. Does anybody else think they're trying it on, or being fair? Obviously I haven't authorised that yet, and it is the first time I have used this garage so don't know much about their honesty yet.

Edit: Forgot to mention, spark plug tips were a nice brown colour when I changed them, pretty normal IMO, what would you be looking for there if the head gasket was leaking?