940 timing anomaly

Gunnar Eikman took the time to write...:

great idea - when the rain stops I will give that a try.... Thanks !!

Reply to
billy_bunter
Loading thread data ...

Although with the 1172 cc Anglia you needed three hands to adjust the tappets.

Cheers, Peter.

: : >>Ok, I used another timing light, same results, the timing mark is still at : >>about 3'o'clock, so about 30 degrees out ?? : : > Surely 3 o'clock would be over 90 degs out? This still doesn't make : > any sense. : : > I wonder if the crank pulley has been reassembled without it's key, : > depending entirely upon the bolt being done up tight enough to stop it : > slipping - which it has? : : Yes - 90 degrees, geometry never was my strongest subject... : I now have another clue - apparently there are a couple of locating pins on : the rear of the bottom pulley that can shear off, leaving the pulley to : move independantly of the shaft sometimes. : : I still fail to understand how it runs under these conditions, but I am : forced into seeking professional help now - It's beyond me. I have a local : man that thinks the bottom pulley is at fault, he is going to test the : ignition electrics and look at the pins.... watch this space ! : : Why are these volvos so damned complicated?? : Bring back the anglia !! : (a 9/16th and a screwdriver was all you needed for a full strip down)

Reply to
Peter Milnes

The fact that your lambda light was on was the most important piece of information. It's too late now, but when the lambda (or check engine) light comes on, the computer has something to tell you. Learn how to find out, and what it means at:

formatting link

Reply to
Mike F

Mike F took the time to write...:

Thanks for that link - The codes all come back as 1.1.1, and presumably removing the battery has NOT cleared the memory - so there is nothing there to find ???

Reply to
billy_bunter

No, disconnecting the battery for a period of time resets all the memories and turns off the light. If the problem persists, hopefully the light will come back on, give you a code and point you in the right direction for repair.

Reply to
Mike F

Mike F declared:

whoops.....

Reply to
Bigjon

billy_bunter declared:

Ok, after much huffing and puffing, the bottom pulley was removed, and it had slipped. The guy found a replacement, checked it all and the timing is now OK. I had the car put on a compy for ignition diagnostics, no problems. The readouts were all fine, bar a "slight misfire" that is STILL unexplained. - There is nothing electrically amiss. The fuel system is OK. The ignition is OK. The emissions are OK. Why is it still misfiring - albeit ever so slight, enough to still dip the revs from 650 to 400 on idle intermittently...and it still stalls in traffic queues. Once the revs hit around 2000 it seems 100% ok ...

Could this be something like a sticky valve or even a broken valve spring? If so, what would that entail to get fixed - am I looking at a main dealer jobby @£40 an hour ??

( I'm in the North West UK, Wigan area, if anyone knows a good Volvo mechanic local to me )

Reply to
Bigjon

Ok, after much huffing and puffing, the bottom pulley was removed, and it had slipped. The guy found a replacement, checked it all and the timing is now OK. I had the car put on a compy for ignition diagnostics, no problems. The readouts were all fine, bar a "slight misfire" that is STILL unexplained. - There is nothing electrically amiss. The fuel system is OK. The ignition is OK. The emissions are OK. Why is it still misfiring - albeit ever so slight, enough to still dip the revs from 650 to 400 on idle intermittently...and it still stalls in traffic queues. Once the revs hit around 2000 it seems 100% ok ...

Could this be something like a sticky valve or even a broken valve spring? If so, what would that entail to get fixed - am I looking at a main dealer jobby @£40 an hour ??

( I'm in the North West UK, Wigan area, if anyone knows a good Volvo mechanic local to me )

Reply to
Bigjon

Hmm.. If you have a misfire, then at least one of these is *not* OK.

650 rpm is a bit on the low side for idle. I'd tweak it up to 800 or more. This may help to even out any irregularities.

Maybe. But I'd do some more diagnostics first, before taking off the cylinder head. Check out all your ignition components. Check for induction leaks, run a compression test...

Don't even start thinking about this yet.

Reply to
Stewart Hargrav

My 740 had a slight misfire when the intake manifold gasket was messed up so the injector was spraying on it, you could have your injectors cleaned and matched, and check the gasket, it's cheap.

Reply to
James Sweet

James Sweet took the time to write...:

Ok, Injectors and gasket next then -

Many thanks for the continuing GREAT advice here !!

Reply to
billy_bunter

Stewart Hargrave took the time to write...:

I have now raised the idle, and replaced the Idle control valve... Still spluttering up to about 2000....

Reply to
billy_bunter

unexplained.

That still sounds like ignition though, my injector issue only caused a noticeable misfire at idle, but then again it's only about $40 to have the injectors cleaned and reconditioned, can't hurt.

Reply to
James Sweet

I have not tried it myself but "starting gas" (may not be correct English word) is supposed to be great for intake manifold leak detection (including gaskets and injector seals).

Let the car idle while spraying starting gas along possible leak locations. If idle rpm changes, you have a leak. Due to fire hazard I would do this outside on a day with little wind.

Reply to
Gunnar Eikman

Gunnar Eikman took the time to write...:

Hmmm... you are more daring than I am !! I think I will give that idea ( I think you mean "easy start" ) a miss. I'm off to find an injector seal set tomorrow, and a Gasket.

Watch this space....

Reply to
billy_bunter

Alternatively, just use water. I trickled water over my injectors and manifold gasket to find a leak. Usually a small leak will be temporarily sealed by the water and idle will improve for a short while. In my case the leak was so bad that the water was drawn in and stalled the engine. Either way, the leak is obvious.

Reply to
Stewart Hargrav

Or WD-40, which, by the way, also works as starting fluid and I argue is preferable for that use, because it is not as explosive as ether!

Reply to
Jim Carriere

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.