Compression Test

[jmkinmsp]

I am doing a compression test and I understand that the easiest way to get at all the spark plugs is to remove the intake manifold. My questions is, do you run the comression test with the intake manifold and throttle body removed from the engine? It just seems odd to me but maybe im just slow. (maybe thats why they made me ride the short bus to school).

Thanks...Jeff

 

[fred79]

since your not going to run the engine while you have a pressure gauge attached to your cylendars there is no reason to have teh throttle body on the engine and all the intake runners to is direct the air into the intakes from the TB/maf/filter.

 

[billyshoe]

Engine warm, plugs removed, wide open throttle.

 

[DavidT]

my sho dynod at 160 hp and 170 tq.
First thing I need to do is check the compression. \
I am confused, can you elaborate, billyshoe?
1. Does the intake manifold/ TB come off?
2. Would a cylinder balance test reveal any headgasket problems?
3. Mainly, is it even possible to check the 3 REAR cylinders WITHOUT removing the intake manifold?
4. I read that running the car in idle with a coolant system pressure tester (letting it get warmed up and revving it a bit) would tell of any headgasket failure. Is this true?

BTW, I am going through lots of oil, not sure how much of it is due solely to LEAKS... I do notice lots of smoke out the tail pipes upon heavy accel./high rpms. When I had it on the dyno, I got out of my car while it was in idle (after the 4th run). Lots of whiteish colored smoke was coming out of the passenger pipe. (this is the side that I speculate I may have a stopped up muffler shrug ). I smoked up the garage pretty good when I was accelerating on the dyno.

<small>[ August 30, 2003, 09:39 PM: Message edited by: DavidT ]</small>

 

[DavidT]

before this gets lost in the x files...
BUMP

 

[olympic]

#1- no it's not required to take the intake off if you can get the tester into the spark plug hole. If you do it this way, make sure the throttle is held wide open during the test so the engine doesn't have to fight for air.

#2-possibly. Depends how bad the leak is. The balance tests work best for cylinders that are completely dead. i.e-fouled plug, burnt valve, bad injector.

#3-should be possible, but surely easier to do with the intake off. The intake and TB are not required to be installed to do a compression test.

#4-yes

I'll just add to the above that all 6 plugs should be out before beginning a compression test.

 

[DavidT]

thanks thumb
Think I'll try just the coolant pressure tester test
question........ I think I am burning oil... would a blown head gasket cause that? In other words, would a coolant pressure tester show me THAT? OR do I need to do a compression test (to see if my oil loss is there)?
OR is the oil problem totally unrelated to this area?
I have lots of oil loss (1 quart/ 300 miles), but have not noticed ANY coolant loss (engine cold, the coolant level is ALWAYS up to the radiator cap) shrug
If I am only burning oil, should there be THAT much power loss?
In my case, do I NEED to do a compression test, or will the coolant pressure tester suffice?

<small>[ August 31, 2003, 12:36 PM: Message edited by: DavidT ]</small>

 

[olympic]

A blown head gasket won't cause oil burning. I'm betting you have 1 or more bad piston rings. A bad ring will cause oil burining as well as compression loss. So it looks like an engine tear down is in your future. Good luck....