Low compression

[popwarbunny111]

I have had low compression for about a year.
I have had some weird problems regarding no starts because I kept thinking it
was something else.
The car starts now with some playing around with Power transistors. It just takes two people.
I did a Compression Test and got like 60 psi across the board. give or take 3 to 4 psi difference.
I did a oil cap tap test and it went up to about 70 psi. I was told that if it jumps up any mount of number that it is a good indication that is piston rings.
Okay, I knew that if it goes up it is a indication that its piston rings. I just thought that it had to go up a significant amount like 20-30 psi difference.
The car runs fine after it gets running. To me it seems to be boosting ok without any smoking from the tale pipe. There is a question in my mind about that as well. .
The main question about this thread that my buddy and I were wondering is if Compression was 60psi across the board would the car even start and run?
Because We have read people with 80-90 psi across the board wouldn't start.
I don't have bigger fuel pump, bigger injectors. Just 2g 450's. No air filter. haha. stock 14b turbo. the car is stock mitsubishi gsx awd. all stock.
Would the car even start with 60 psi across the board?

 

[talontd92tsi]

60psi is VERY low, there is a serious issue here. I would strongly suggest a leak down test.

 

[NOSLO2PT0]

Sounds more like your timing jumped a tooth if it's that low across all 4. Verify the engine is still in time.

 

[BogusSVO]

are you sure the compression gauge is accurate?

at 60 psi... I doubt it would start.....

 

[TFFC]

See, what did I tell you, do a leak down test, and seems like timing is off! If your still interested, I will come check out the car next week.

 

[popwarbunny111]

See, what did I tell you, do a leak down test, and seems like timing is off! If your still interested, I will come check out the car next week.

I never said you were wrong. I just don't know how the car is even running after doing the compression test. It was just a interesting thing to find out the if compression was 60psi across the board while doing a compression test the right way, I just don't get it.
I mean even if timing was off and it slipped a tooth, still the compression is 60psi across the board. Even if valves are bent or not seating right, the compression is still 60psi. A leak down test would just tell me where it's leaking out at. Either exhaust valves, Intake Valves, Intake seals. intake manifold gasket. or piston rings. It was just a post asking if the car would run with extremely low compression. Extremely low compression......
I do know that the car does run because I can drive it . It'll start almost every time in the summer, its just a looser in the winter.
and yeah buddy I'm still interested. Thanks.

 

[NOSLO2PT0]

Get another comp. tester. The cheap ones from Autozone go bad. I got one here that doesn't read any higher than 90psi. Borrowed my buddies and the engine comp. instantly went up to 150 across the board. Could be a bad gauge.

 

[popwarbunny111]

could be the gauge, I thought about that but i kinda pushed it off because it was fairly new and I was like nahhhh..couldn't be that. and by buddy did his like a few weeks before I did mine with the same one and mine was like crap.. Like badd..I was like dang baby. ...

 

[jking29]

could be the gauge, I thought about that but i kinda pushed it off because it was fairly new and I was like nahhhh..couldn't be that. and by buddy did his like a few weeks before I did mine with the same one and mine was like crap.. Like badd..I was like dang baby. ...

What??!! Can someone interpret?

 

[habitatguy187]

What??!! Can someone interpret?

Lol, try talking to him in person. He would seriously say that exact same thing . And yeah it was an autozone gauge, but I used it just weeks before as he said. Guess he could get a new one.

He took it to a tech buddy of mine at the Mitsu dealer to specifically check the timing and he said it was good. I also was shocked that the car would start with such low compression across the board. Looks like it's time to try a new gauge Austin.


The weirdest thing about this car is that once it starts (which can be really hard sometimes) it will drive just fine, boost just fine, absolutely no smoke out of the exhaust. No burning oil or coolant, no weird smells, nothing.

 

[popwarbunny111]

I know Brad. It's time to get a new gauge and check the compression all over again. I don't really get how it worked just fine on your car but when it came time to do my test the numbers looked like crap.
It is the strangest thing that the timing was perfect and runs and drives just fine when running. It just doesn't like starting in the cold by just cranking the key.
I say we take out the plugs and let the car sit longer to see if the flooding thing would cause compression to be that low. try to see if the gas would evaporate out of the cylinders. I don't think even if the car was being flooded that it would cause each cylinder to be 60psi. I know it will make the compression lower, but as low as 60 is crazy.
Brad we just need to talk to that TFFC guy, He said that he wanted to meet up and check this boy out to see how crappy it is.

 

[habitatguy187]

^^^ You need to talk to him . I'm busy enough.

 

[TFFC]

Don't worry about getting a new gauge, I have one, do you have a battery charger? Correct way to check compression is to run car, get up to operating temp. Take all plugs out, put on battery charger so you have equal battery voltage and amps to turn engine over at same rate, and disconnect fuel pressure.

 

[popwarbunny111]

Ohh ok ok. I don't have a battery charger though. I have jumper cable haha.