1.9 m44 1976 😢

[Dazbag66]

Well had new camshaft sensor new idle control new plugs checked all vacum hoses replaced any split still misfire next check coil pack and plug leads anyone know best way check them or any ideas as z3 is getting beyond a joke now lol ????

 

[Dre0415]

Have you checked compression? It's a 2 secound check I always recommend doing when diving into misfires. I know it's a scary check but it needs to be done especially if it's a stick shift. If you want to check plugs and coils easily remove all plugs and coils hold the plug and coil you want to check to a metal surface ond the engine so it's grounded and have someone crank the engine over. You should see the spark. If you don't then there's your problem

 

[Dazbag66]

Have you checked compression? It's a 2 secound check I always recommend doing when diving into misfires. I know it's a scary check but it needs to be done especially if it's a stick shift. If you want to check plugs and coils easily remove all plugs and coils hold the plug and coil you want to check to a metal surface ond the engine so it's grounded and have someone crank the engine over. You should see the spark. If you don't then there's your problem

how best way check compression cheers

 

[Stevo7682]

how best way check compression cheers

You need a compression tester for this.
When we picked up our 2nd zed wasn't running right ( knew that when bought) throwing up misfire codes and poor starting. After other checks which checked out done a compression test down on 1 and 2 after removing the cylinder head suspected head gasket failure unfortunately mine turned out to be more serious as it had a cracked cylinder head which had to be replaced.
You need to get it diagnosed properly before you chuck any more money into it on parts that are OK.
Stephen.

 

[t-tony]

You need a specific compression tester to do this. Have a look on eBay or Amazon search "compression tester".

Tony.

 

[the Nefyn cat]

Were all the old plugs the same colour? And the right colour, too? Should be a digestive biscuit pale brown-ish shade. If there was one (or more) dark brown/black that'll point you in the right direction. If you've managed to get a few miles on the new plugs they may tell a tale, too.

 

[Kennethmilesthethird]

Start at the root - do you know what cylinder is misfiring?

Misfires happen within the cylinder. Cylinders need electrical, fuel, and air. Electrical and air are the easiest to check:

Spark - an inline spark tester. Don’t do the “test the spark by holding it against the frame” process. That test is binary - it will only tell you if you have a spark. A weak OR intermittent spark can still cause misfires, and won’t necessarily be caused by a bad plug. Compare the inline tester light brightness between plugs - if one is off or noticeably weaker in comparison to the rest, you’ve got your man. The spark tester should be BRIGHT and CONSTANT if operational.

compression - yes to the above, get a solid compression tester kit. Basically a pressure gauge that fits into the spark plug threading. Make sure you get the kit that fits your spark plug port. Remember that the “compression” reading itself is useless. There has to be a 1.9l compression chart out there (I have yet to run compression on my 1.9l, but now I’m interested!!). Compression should be comparable across all four cylinders, and greater than 90PSI.

Tell us you’re all green after compression and electrical, and we’ll go down the fuel root with you.

 

[Kennethmilesthethird]

You will want to do a leak down test too if you’re green in compression and electrical.

 

[t-tony]

It’s more important for cylinder pressures to be equal as much as reaching a required figure.

Tony.

 

[Kennethmilesthethird]

It’s more important for cylinder pressures to be equal as much as reaching a required figure.

Tony.

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