menappi

ok so my car wont start, i checked everything (spark, fuel, timing, etc) and i just did a compression test now and heres the results. i did it three times each cylinder and the numbers kept changing so ill post each try.

1 2 3 4
50 50 55 85
30 70 65 85
80 90 60 100

i cranked the engine each time until the guage stopped moving, usually around 5 seconds. i have an 88 crx hf with a d16a6 in it. i need some help on what to do or how to fix it. i know its probably something pretty big. oh and the after the 1st tries, i put a little oil into the cylinder which made the numbers increase as you can see, for the most part. ECU throws no codes. oh and i did the test while COLD, becuase it WONT START! i dont understand why the numbers are soo random. ANY HELP would be greatly appreciated! thanks.

Sham

Crank it the same # of times for each cylinder, gotta be consistant (I think its like 3 or 4 times, for the # of cranks)

menappi

ok well, someone replied to this same post in honda-tech and said something abotu piston rings? also one person said that the same thing happened to him (no compressino tho) and he took thehead off and saw LOTS of carbon. but i thought that the more carbon u have the higher the compressino will be? anyways..what kind of a job is taking the head off and how hard is it to change piston rings?

S2Kev

Yeah keep doing it until you get consistent results. Make sure you're on the right stroke. It could be piston rings, valve seats, head gasket, or spark plug. Try using a soft rubber mallet and tap the valves to lift the dirt out of the head so that they seat properly and do another compression test.

To take the head off, untorque the bolts beginning from middle and move your way out in a circular pattern. To prevent cylinder head warpage, do NOT remove bolts all at once, instead loosen each bolt by two turns each.

Changing piston rings is easy. Remove the piston from the block, get a piston ring plier to spread the ring and take it off the piston. To install spread the ring and put it around the piston. And before you install your piston back into the block, you have to align the piston rings a certain way. The piston rings gap shouldn't be aligned together. It'll say in your manual. It'll show a picture of which way each piston ring gap should be faced.

Also, before you do all this, get a service manual. Good luck.

1stGenCRXer

How many miles are on the engine?

menappi

it has 90k or so the guy told me who had it in his car...how much work is it replacing the piston rings..? do u think someoen who can barely change the oil can do it with a gay ass chiltons manual, cause thast all i have and that thing is a piece of shit! if i had 80 bucks i would get a helms..

S2Kev

To replace piston rings, you need to remove the pistons out of the block.

For a person who can barely do an oil change, I recommend you don't try to attempt to do any engine work for now.

91_Hulk_Si

They call it a 4 stroke compression test because you unhook the spark plug wires and crank the engine 4 revolutions. By that time pressure should have gradually built on the guage. I remeber I did mine and they where like 90-120. Then I squirted some oil in the cylinder to get a better seal and it started reading 120-150. So I had great compression. When I took the block apart I saw that the head gasket was letting oil into the cylinders. But I replaced the rings just to be safe. Runs great now.

1stGenCRXer

No... they don't. It's a 4 stroke compression test because that's what kind of engine it is.

Make sure when you do a compression check you remove all spark plugs, hold the throttle at wide open, and crank until the guage doesn't increase any more. That's the only truly accurate way to do a compression test, period.

91_Hulk_Si

You are so wrong. But thanks for playing. And holding the throttle open will only increse the numbers. Which will make you think you have great compression. And once you have acheieved compression watch the decent of the pressure in relation to the other cylinders.