| MayanArch |
Posted
Monday, Nov 26th 8:32pm [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 1463
Florida, USA
Baur E21 2.7 1982, Baur E30 318i 1985, 323i 1978 |
OK, so are those auto parts compression test meters any good?
What are the steps to doing a good compression test on an E21?
Remove all spark plugs?
Start on any particular cylinder?
How would you disable the coil? Do you need to?
If anyone can help...please go into detail.
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| wayfast |
Posted
Monday, Nov 26th 10:34pm [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 15
Belleville, Michigan
81 323i |
make sure you have a good battery, pull all the plugs out, take out the fuel pump relay. when i did mine i just cranked until the gauge stopped moving. when you do it, do it WOT
you should disable the coil, not really sure how. when i did mine i didn't and it was ok. |
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| MayanArch |
Posted
Tuesday, Nov 27th 2:02am [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 1464
Florida, USA
Baur E21 2.7 1982, Baur E30 318i 1985, 323i 1978 |
What difference does WOT make......since you have taken out the spark, the electricity, and the gasoline from the system? What is it throttling?
I am confused as to how this works. |
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| wayfast |
Posted
Tuesday, Nov 27th 4:19am [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 16
Belleville, Michigan
81 323i |
to tell you the truth, i have no clue.
thats just what i've read, and what i've been told...
so thats how i did it. |
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| KenDanielson |
Posted
Tuesday, Nov 27th 7:06am [Edit] [Quote] [IMS] [View car] |
Junior Member
Post nr. 192
Petaluma CA
'82 320is, '78 320i |
The point of WOT during cranking is to allow the max amount of air into the engine for the best/most consistent reading.
Ground the coil wire that goes to the center of the distributor cap.
ken |
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| MayanArch |
Posted
Tuesday, Nov 27th 4:56pm [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 1466
Florida, USA
Baur E21 2.7 1982, Baur E30 318i 1985, 323i 1978 |
| KenDanielson wrote: | The point of WOT during cranking is to allow the max amount of air into the engine for the best/most consistent reading.
Ground the coil wire that goes to the center of the distributor cap.
ken |
I guess a better way of phrasing the question is....how is the engine going to produce air compression if it has no ignition, spark, or gas?
I guess I will try it. |
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| aussie323i |
Posted
Wednesday, Nov 28th 1:07am [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 597
australia
1979 323i |
because the starter turning over the motor will still make it go through the combustion cycle even though you have no fuel or spark!
Basically it is just a big air pump at that point  |
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