Testing Engine Compression on '94 E320 HFM engine
 

Hi Guys,

Any advice on the best method of checking engine cylinder compression on Ser 104 engine (with HFM controls) ?

I was proposing to :
1. Remove Fuel Relay
2. Disconnect low voltage inputs to the 3 coil packs. Then remove one plug at a time.
3. Use a screw-in Engine Compression Tester to check pressure.

Your comments would be welcome.

allan l

'94 E320 Coupe

RE: Testing Engine Compression on '94 E320 HFM engine
 

better remove all spark plugs to reduce load from the battery.

removing the connector from crankshaft position sensor on EZL will also disable the ignition.

yes, screw-in type is better.

crank 8 times is always better result.

do wet compression test too. you might need the value for making decission.

RE: Testing Engine Compression on '94 E320 HFM engine
 

Sleepwalker,

Many thanks for your advice on above exercise.

How do you do a "wet test" on cylinders ?

allan l
'94 E320 Coupe

RE: Testing Engine Compression on '94 E320 HFM engine
 

can spray a little penetrating oil on the cylinder wall.

RE: Testing Engine Compression on '94 E320 HFM engine
 

Sleepwalker,

Many thanks again for your latest advice.

allan l