Compression testing cost?
10-05-2007, 03:18 PM
#1
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Location: Columbus, GA
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Compression testing cost?
I was quoted from a Porsche dealer up in Atlanta that a compression test would run me $400!!! Does this sound accurate? I didn't think it would be but at most half that, then again I am new to this sort of testing.
10-05-2007, 03:54 PM
#4
Nordschleife Master
http://cgi.ebay.com/ebaymotors/Gas-E...spagenameZWDVW
http://autos.yahoo.com/maintain/repa...ques056_1.html
http://64.78.42.182/sweethaven/MechT...Num=7&modNum=6
For $400 , I will fly to Columbus, GA , do the test , then fly back to california . I will bring tools and a comp tester .
http://autos.yahoo.com/maintain/repa...ques056_1.html
http://64.78.42.182/sweethaven/MechT...Num=7&modNum=6
For $400 , I will fly to Columbus, GA , do the test , then fly back to california . I will bring tools and a comp tester .
this actually looks pretty simple!
10-05-2007, 04:31 PM
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To check compression, all the spark plugs are removed. The ignition coil is then disabled or the high tension lead is grounded. The throttle is also held open.
The above was taken from the DIY in a previous response. Couple more questions arise, and I am sure they are redundant and ridiculous to most, but please bear with me!
1. How do I disable the ignition coil?
2. To hold the throttle open, does that just mean that whoever I have trun the car over, that I also have them hold the throttle all the way down?
The above was taken from the DIY in a previous response. Couple more questions arise, and I am sure they are redundant and ridiculous to most, but please bear with me!
1. How do I disable the ignition coil?
2. To hold the throttle open, does that just mean that whoever I have trun the car over, that I also have them hold the throttle all the way down?
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10-05-2007, 05:23 PM
#8
Nordschleife Master
"To check compression, all the spark plugs are removed."
Your car has 12 plugs , only 6 need to be removed .
If you did remove all 12 , you would have 0 compression .
1. How do I disable the ignition coil?
Pull the connector off of the ignition switch thats in front of the coil .
2. To hold the throttle open, does that just mean that whoever I have trun the car over, that I also have them hold the throttle all the way down?
That will work .
That person , would be you .
Pull the plugs , screw in the gauge , walk up to the cab , turn the key , let it crank ten puffs , walk back and write down the number . Release the pressure from the gauge .
Unscrew the gauge , move it to the next cylinder , repeat .
Your car has 12 plugs , only 6 need to be removed .
If you did remove all 12 , you would have 0 compression .
1. How do I disable the ignition coil?
Pull the connector off of the ignition switch thats in front of the coil .
2. To hold the throttle open, does that just mean that whoever I have trun the car over, that I also have them hold the throttle all the way down?
That will work .
That person , would be you .
Pull the plugs , screw in the gauge , walk up to the cab , turn the key , let it crank ten puffs , walk back and write down the number . Release the pressure from the gauge .
Unscrew the gauge , move it to the next cylinder , repeat .
10-05-2007, 05:42 PM
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It is better to have 2 people.........you need to see what the guage reads on the first pulse and relate that to the final reading. And it is pretty hard to do it just right by yourself to get that one single pulse.
This is called the dynamic compression reading.......and is just as important as all the other readings.
If the first reading is only 40 PSI (for example) and after 10 or so cycles you could get it up to 175 PSI......you potentially have problems.
This is called the dynamic compression reading.......and is just as important as all the other readings.
If the first reading is only 40 PSI (for example) and after 10 or so cycles you could get it up to 175 PSI......you potentially have problems.
10-05-2007, 05:49 PM
#11
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Here is the procedure for a quick compression check. This lets you know if you need to run the full compression test:
1) Disable both ignition systems
2) Crank the engine. It will not start, but the chug-chug-chug of the compression strokes should all sound identical. If one sounds faster than the others, you have a bad cylinder. It is rare, but possible to have more than one bad cylinder, but if you have even one good one, the "even chugs" test will deterimie if there is a problem.
Spark plugs are supposed to be replaced every 15,000 miles. Why not wait, and have it done while that is done? I can't believe a shop would charge for more than an extra hour if the car is in for a tune-up.
1) Disable both ignition systems
2) Crank the engine. It will not start, but the chug-chug-chug of the compression strokes should all sound identical. If one sounds faster than the others, you have a bad cylinder. It is rare, but possible to have more than one bad cylinder, but if you have even one good one, the "even chugs" test will deterimie if there is a problem.
Spark plugs are supposed to be replaced every 15,000 miles. Why not wait, and have it done while that is done? I can't believe a shop would charge for more than an extra hour if the car is in for a tune-up.
