Questions tagged [compression-testing]

Compression testing is the act of testing the air pressure generated by a cylinder in an internal combustion engine.

Filter by
Sorted by
Tagged with
13 votes
4 answers
5k views

Diesel runaway - stopped miraculously by itself

A little background (Little longer, please excuse): Few days before while we were driving Maruti Suzuki Dzire vdi (Engine: Fiat Multijet 1.3 DDIS, CRDI engine) around 40kmph. All of sudden there was ...
user avatar
  • 235
11 votes
3 answers
2k views

In Cylinder Pressure Testing With a Pressure Transducer and a Oscilliscope

Recently I've been looking into buying a higher PSI pressure transducer to do in cylinder pressure testing. I've encountered vehicles which would of benefited from this approach and wish I had thought ...
user avatar
  • 10.7k
10 votes
1 answer
398 views

More In Cylinder Pressure Testing Questions

So I was looking at a 06 Pontiac G6 2.4l with a complaint of low power on hills. Had been at another shop to have the transmission checked and they referred the customer to us. Road test confirms car ...
user avatar
  • 10.7k
7 votes
4 answers
3k views

Is it ok to plug in battery backward to do compression test?

On engines with compression release valves, the recommended method for testing compression is turning the engine in reverse direction. I'm working on a lawn tractor (with a Kholer K241AQS), so there ...
user avatar
  • 5,225
7 votes
1 answer
1k views

What are these two rubber-ended attachments used for in a compression tester kit?

I'm looking to buy a compression tester kit and am a little puzzled by the purpose of the two rubber-ended attachments shown below. Am I right in assuming that these two attachments can be jammed ...
user avatar
  • 39k
7 votes
1 answer
15k views

How to leak down test a cold engine?

I'm thinking of doing a leakdown test on an engine before I install it in my car. Of course the problem is that the engine will be cold and things won't seal the way they do when they are hot. So how ...
user avatar
5 votes
3 answers
16k views

Used Car Condition - Is a Compression Test a good proxy of engine health? (and what's a leak down test?)

I'm looking to buy a used car and aside from the advice here (which is mostly functional) I want to know if the oil has been changed "enough" to prevent gunk build up that could starve parts from ...
user avatar
  • 163
5 votes
1 answer
4k views

Engine consuming oil and white smoke comes out when starting the engine while cold

my car has been consuming oil for a while now but only recently has started to smoke when it is started while the engine is cold. I thought that maybe because I am using a synthetic oil in a high ...
user avatar
  • 2,750
4 votes
3 answers
5k views

Low compression on all cylinders - Flooded Engine - Maybe Washed Cylinders?

I just did a head gasket replacement on my 1995 Acura Legend. Before the replacement, compression was good on all cylinders except #3, which had blown. While the engine was open: I cleaned off the ...
user avatar
  • 153
4 votes
2 answers
485 views

If an engine starts does that mean compression is fine?

I am looking at buying a second hand 2-stroke engine. I have seen a lot online about checking compression before buying used engines. I don't have a compression tester, but will buy one if necessary. ...
user avatar
  • 43
4 votes
1 answer
53 views

Toyota corolla verso 1.794 petrol vvt-1-t2 [closed]

Recently Purchased Vehicle @milage 81.075 in the past vehicle has consumed 5.25 Litres of oil a full oil composition test was carried by my Garage. They also advise it is an uneconomical repair it has ...
user avatar
3 votes
3 answers
937 views

Are compression tests neccessary?

A friend told me when buying a car compression tests are not necessary since if there were problems you would hear the engine misfire so just listening to engine is enough. I'm currently ...
user avatar
  • 2,714
2 votes
1 answer
128 views

Where in a Haynes manual would the compression figures be for my engine?

Often I've read on Google to consult my manual for the compression figures for my engine but just can't them listed. I have a 1979 Leyland Sherpa 230 with a Morris "O - Series" engine 1.7l. I ...
user avatar
2 votes
1 answer
669 views

How to interpret slightly varying compression between cylinders?

I have a 99 Toyota Corolla with 255k miles. According to the service manual, cylinder compression should be 145-218 psi, with no more than 15 psi variation between cylinders. I tested mine and read ...
user avatar
2 votes
2 answers
179 views

Replaced Head on Propane Engine; Now I have too high compression. Why?

I hade a misfire in my propane burnisher (buffer). The Exhaust valve is stuck and wont move, as a result the push rods bent. Manufacturer recommended I get a new head. I replaced the head according to ...
user avatar
  • 21
2 votes
1 answer
72 views

Engine Burned Oil | Trying to Diagnose with Compression Meter

I changed the oil in my car (1997 Volvo S90 with approx 200k miles on it) about 2k miles ago, and recently took a couple long car trips (~400 miles each, up and down mountain roads, etc). When I ...
user avatar
2 votes
1 answer
2k views

Blown head gasket? (Decent compression numbers but cooling system doesn't hold pressure, no external leak)

I have a Mazda MX-5 and it was overheated due to the water pump belt failure. I replaced the belt afterwards and the car drove fine. I brought the car to the shop and they told me it has head gasket ...
user avatar
1 vote
1 answer
76 views

What would cause the two middle cylinders on my v6 to have no compression and the other four cylinders do?

Mazda 6 3.0 V6. Cylinders 2 and 4 have no compression and the other four do. What would cause this?
user avatar
  • 11
1 vote
0 answers
1k views

Help me understand the results of these cylinder compression and leakdown tests

I recently purchased a 2007 Subaru Outback 2.5i, with approx 146000kms on the clock. As its a recent purchase, I'm going through preventative maintenance to ensure its running as good as possible. ...
user avatar
  • 934
0 votes
1 answer
59 views

Compression testing a 2-stroke boat motor

On an outboard two stroke engine, what tests can I do with a compression tester, (and how to carry them out)? It's a Yamaha 200 hp V6 2-stroke boat engine.
user avatar
  • 428