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No fire on #3 cylinder?

Do you mean you swapped over the injector itself, or just the connectors? I'd read your previous post as if the injectors had been in their original positions all along. If you really did swap the injectors themselves over, that puts a whole new complexion on it.

Injector cleaner down the inlet won't clean the injectors. The only way to get it to go *through* the injectors is to mix it with the fuel. Even then, if one is not opening at-all, it won't help.

Yep. I've no experience of poor compression (slightly or otherwise) so I'm still in two minds as to whether it might be an issue.

Cheers,

Colin.

Reply to
Colin Stamp
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Yes I had already swapped the actual injector around. The #3 injector worked ok in #4 but 4 still didn't fire #3 cylinder. Also swapped the electrical plugs over with the same result and cranked the engine over with the fuel rail lifted out to see the injectors all squirt so I think that pretty much rules out the fuel / injector side.

Reply to
redwood

I believe these are the same lumps as Vauxhall. Would a camshaft problem have shown up on a cranking compression test? I'm just off to do the running comp test now.

Reply to
redwood

A worn cam lobe could give good compressions but give bad running.

Also check any vac pipes that come off the no3 cylinder, inlet manifold runner. Often on Vauxhalls there was a pipe going to a small vac valve that gave problems. It used to split apart creating a vac leak. Also does the brake servo pipe come off no 3 runner?

Graham

Reply to
Graham

I am getting around 50psi at idle on #3 which I think is ok but the gauge on my Gunsons compression tester has broke so I can't complete all the tests. Will need to get a new gauge but the puffs of air from the compression tester valve appear similar across the cylinders.

Everything appears connected can't see anything coming off #3 inlet. Had a look at the EGR valve but that has it's own chamber going back to the main intake block.

Reply to
redwood

Bugger, I missed the "same with the electrical connectors". I assumed it was all with the connectors.

I'd now check the inlet lobe of the cam.

If the inlet is working, but the exhaust isn't, you'd get monster backfires.

If the inlet is not working, you'll get no fuel/air inside the cylinder, but there will still be the opportunity to suck exhaust gas back inside via the partially open exhaust valve.

Maybe :-)

Pete.

Reply to
Pete Smith

Ah. I mis-understood then - sorry. So we've got fuel, spark and apparently good compression but still no bangs - hmmmm....

One thing that might cause all these symptoms would be a stuck-shut valve, maybe a knackered hydraulic tappet or a broken rocker or something.

I think I'd be taking off the cam cover next.

Cheers,

Colin.

Reply to
Colin Stamp

The engine doesn't sound too bad considering #3 isn't working but I suppose the ecu & gizmos will be working overtime. From the exhaust it does make a pup pup pup sound.

Thanks for the replies, my local friendly mechanic is going to take a look Friday but I'm leaning towards it been a problem in the valves or that area.

Reply to
redwood

Had confirmation from the mechanic that it is a worn camshaft lobe. Now deciding if it's worth spending on!

Reply to
redwood

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