<10mpg! Running horribly rich.

[StvC]

Hi all, thought I'd start a new thread away from a intro post to encourage some more input although Paul has been helpful. Car is running very rough, at 1100 rpm. Then it drops to a very lumpy juddery 700rpm and you can just smell the fuel dumping in the system. Paul offered the below advice....but was puzzled by the result.

Originally Posted by Paul240480

Lumpy idle on an E will most likely be that iffy manifold gasket and/or the injector seals. When running lumpy spray summit like carb cleaner around the injectors, then the manifold gasket. If the idle settles, you have found the leak. Manifold gasket is easy, just do get all of the old one off, lol
Injectors, thin seals are a doddle, the fat ones can be a bit of a pain, but do-able.
Best news is that all of that work will come in at about £30 tops for proper OE stuff.

So using easy start, I had hoped to see this result, but when I sprayed the manifold with easy start it actually cut out.

Engine is a B200E, car is an 1988 244 Auto GL.

[Clan]

You need a set of injector holder to head O rings , whilst you are changing them do the injector to holder seal rings too . Air is being sucked in , then people have to richen the mixture to get the engine running better . So when you have changed these seals you will have to get the CO adjusted back to about 1.5 % ... to make the engine run as intended ..

[StvC]

So, the O rings and injector seals need changing and then would you expect the hissing to stop? Or not until the adjustment screw is altered?

[Clan]

Originally Posted by StvC

So, the O rings and injector seals need changing and then would you expect the hissing to stop? Or not until the adjustment screw is altered?

hissing from the injectors ? pour some water around each injector base , if you hear sucking noises they are leaking in air , the engine will probabaly stall . The engine will not run correctly until the CO has been adjusted , assuming someone has tweeked it to run properly with partialy leaking injector seals at some point ..

[StvC]

That's the thing, not sure if the hissing is from injectors or manifold. When I sprayed the manifold with Easy Start it stalled yes.
Maybe now the manifold gasket has been replaced, I just need to adjust the mixture to compensate for the, now correct, air flow. Just wasn't expecting hissing still which is why I assumed there was still a big leak from somewhere.

Could you envisage a scenario whereby adjusting the mixture would stop the hiss? If not, assuming Volvo engines don't hiss normally, I guess it's change the injector seals as a matter of course and if necessary, re-change the inlet manifold gasket again.
Where is the best place to order the seals and O-rings you speak of?

[Derek UK]

IMO not much point in changing things until you've found out the cause of the hiss. Might just be a split in one of the pipes under vacuum, possibly a servo hose but there are several to check. May mean you have to take them off one by one but a small split underneath is all it takes. With a leak the engine will think it's running weak and tell the ECU to add more fuel. Although things get hot pretty quick, a cloth in your hand can wrap round various joins an joints to show a change in the hiss or you can chase it with a length of hose. One end in the ear and the other moving around the top of the engine.

[Paul240480]

The seals will probs be available from your local dealer. Got mine that way tho' I'm in France.
Or from FRF Volvo on here, look in the forum home page for members discounts

As others mention, you have a leak...... Somewhere! That said, if I was you I'd change those injector seals as a matter of course, if they haven't been changed, even if okay they'll be on borrowed time now!

[StvC]

OK, thanks everyone, did the water thing and engine choked right up with the back two injectors.
Will change all 4 and see how we go. Optimistic. Will post back results.

[classicswede]

It is often not just the thick O rings on the injectors but the thinner O rings around the buckets that will also need to be changed It can be worth ordering new plastic buckets. All are still available from Volvo

[StvC]

Indeed, have bought a complete set from Volvo for £10 not sure if this includes the plastic buckets but it does include the seals and O rings allegedly, should be here tomorrow. See how that goes. Still not convinced by the manifold but one thing at a time.
When done and I want to measure the CO? Is it only a gas analyser that can do this? Several people mentioned it which had me wondering if there was multi-meter sized gizmo folk are using. What am I looking at for an ideal mix 1.5 -3%? Not sure where I got that from so could be miles off.