No compression on cyl 4. working on dianosis, want input
#1
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No compression on cyl 4. working on dianosis, want input
might be a little long winded, just wanna get all the info i can in here.
Yes, I have done searching, But the REASON I'm posting asking first is cause what I have found is vague and requires steps I'm hoping to narrow out before I start.
First, the water pump, oil pump and t belt were all replaced. the timing was off about a tooth at the crank. It was freezing cold outside so I adjusted the distro to make up the timing diffrence, and it did it pretty well till it warmed up enough to fix the t-belt.
fixed the t-belt timing, put the distro back and set everything up right with a laptop and a obd2 tool. replaced plugs for good measure cause i had been running rich and they looked like crap.
test drove it on highway (didnt break any laws mods), got a CEL, passenger checked it with the laptop, vtec issue. checked oil with dipstick, was low but didnt throw a oil light. assumed that was the issue, wiped code, added oil. tested it again. went to about 7k in a few gears, vtec fired off each time without a hitch, no CEL (yet, i know they can take time though). stopped at a toll booth. started taking off again. started to accel fine. then felt power drop.
dropping a cylinder. tested by pulling plug wires. pulled cyl 4, cloest to distro, and no difference. handheld obd2 scanner read misfires in 1,2 and 4 and a p1300 manu. ignition control issue.
took home, did a compression test. cyls 1,2,3 all read between 170-190. cyl 4 read 0. did with fuse pulled and at WOT.
read that putting a little oil in the cylinder would seal it up temporarily if its a ring issue. did that. still 0 on the compression gauge.
popped fuse in, started it with tester on, read 30. not sure if its normal but i have a LOT more air than normal coming out of the oil cap when running, but maybe thats in my head.
ive read it can be a ring, hole in piston, unlikely a headgasket, broken valve, valve seat damage, bent valve or a valve seal.
Is there something else i should be checking? like maybe under the Valve cover to get a better idea first? any input before i go taking the head off would help cause this is new territory to me, never been inside an OHC engine of any kind before and these bastards are expensive to work on compared to a sb chevy.
any input would be greatly appreciated. i dont have the stuff for a leakdown test at hand so i havent/cant do one at the moment but i have plenty of other tools.
also, the head, especially at the head gasket level on the cyl 4 side of the engine seeps a lot of oil out compared to the t-belt side of the head.
found a bunch of threads but two most useful threads i found:
https://honda-tech.com/forums/acura-integra-6/no-compression-cylinder-four-help-3012788/
https://honda-tech.com/forums/acura-integra-6/compression-test-help-3010425/
Yes, I have done searching, But the REASON I'm posting asking first is cause what I have found is vague and requires steps I'm hoping to narrow out before I start.
First, the water pump, oil pump and t belt were all replaced. the timing was off about a tooth at the crank. It was freezing cold outside so I adjusted the distro to make up the timing diffrence, and it did it pretty well till it warmed up enough to fix the t-belt.
fixed the t-belt timing, put the distro back and set everything up right with a laptop and a obd2 tool. replaced plugs for good measure cause i had been running rich and they looked like crap.
test drove it on highway (didnt break any laws mods), got a CEL, passenger checked it with the laptop, vtec issue. checked oil with dipstick, was low but didnt throw a oil light. assumed that was the issue, wiped code, added oil. tested it again. went to about 7k in a few gears, vtec fired off each time without a hitch, no CEL (yet, i know they can take time though). stopped at a toll booth. started taking off again. started to accel fine. then felt power drop.
dropping a cylinder. tested by pulling plug wires. pulled cyl 4, cloest to distro, and no difference. handheld obd2 scanner read misfires in 1,2 and 4 and a p1300 manu. ignition control issue.
took home, did a compression test. cyls 1,2,3 all read between 170-190. cyl 4 read 0. did with fuse pulled and at WOT.
read that putting a little oil in the cylinder would seal it up temporarily if its a ring issue. did that. still 0 on the compression gauge.
popped fuse in, started it with tester on, read 30. not sure if its normal but i have a LOT more air than normal coming out of the oil cap when running, but maybe thats in my head.
ive read it can be a ring, hole in piston, unlikely a headgasket, broken valve, valve seat damage, bent valve or a valve seal.
Is there something else i should be checking? like maybe under the Valve cover to get a better idea first? any input before i go taking the head off would help cause this is new territory to me, never been inside an OHC engine of any kind before and these bastards are expensive to work on compared to a sb chevy.
any input would be greatly appreciated. i dont have the stuff for a leakdown test at hand so i havent/cant do one at the moment but i have plenty of other tools.
also, the head, especially at the head gasket level on the cyl 4 side of the engine seeps a lot of oil out compared to the t-belt side of the head.
found a bunch of threads but two most useful threads i found:
https://honda-tech.com/forums/acura-integra-6/no-compression-cylinder-four-help-3012788/
https://honda-tech.com/forums/acura-integra-6/compression-test-help-3010425/
#3
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Re: No compression on cyl 4. working on dianosis, want input
well since u ran the car with the belt off a tooth u mighta bent a valve.. was it the intake cam or exhaust cam that was off the tooth.. also i would do a leak down test now and see if its ur valves
#4
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Re: No compression on cyl 4. working on dianosis, want input
the tooth that was off was at the crankshaft, not at the cam gears, they were lined up correctly when we fixed the t-belt.
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Re: No compression on cyl 4. working on dianosis, want input
A leak-down test will tell you, my guess is a valve, either bent, burnt or broken, although you could get lucky and it is just a valve that is too tight, check the valve lash on cylinder 4 valves.
The other possibility is a hole in the piston, you will need to pull the head to confirm, or a borescope, you may be able to rent one. 94
The other possibility is a hole in the piston, you will need to pull the head to confirm, or a borescope, you may be able to rent one. 94
#7
Re: No compression on cyl 4. working on dianosis, want input
with it running, see if there's air coming out of the dip stick tube.
as stated, check the lash. it may be too tight. or if it's extremely loose, bent valve.
those are things you can check besides the leakdown. with zero compression, oil in the cylinder won't do anything. but because you said the oil didn't go anywhere, i'd suspect valve(s). check the lash.
as stated, check the lash. it may be too tight. or if it's extremely loose, bent valve.
those are things you can check besides the leakdown. with zero compression, oil in the cylinder won't do anything. but because you said the oil didn't go anywhere, i'd suspect valve(s). check the lash.
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#8
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Re: No compression on cyl 4. working on dianosis, want input
gonna go check the dip stick tube right now.
how do i check the valve lash? ive read 3 threads on adjusting valves but im not really too sure which part of that was checking them, they just tell you how to adjust them, use the feeler gauge, then tighten them back up, which actually sounds like a process im probably gonna need to do if this doesnt result in me having to get my head rebuilt :-/ im hoping to DIY this as much as possible.
how do i check the valve lash? ive read 3 threads on adjusting valves but im not really too sure which part of that was checking them, they just tell you how to adjust them, use the feeler gauge, then tighten them back up, which actually sounds like a process im probably gonna need to do if this doesnt result in me having to get my head rebuilt :-/ im hoping to DIY this as much as possible.
#9
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Re: No compression on cyl 4. working on dianosis, want input
yeah there's air coming out of the dipstick tube. im waiting for my dad and one of my friends to get off work to see if either of them has a leakdown tool for the compressor. on the upshot, i finally have an excuse to put my valve cover in the sand blaster since its coming off.
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Re: No compression on cyl 4. working on dianosis, want input
If air is coming out the dipstick tube it could mean a hole in the piston, a leakdown test shoud give you the same results, air out the dipstick tube and oil filler hole in VC. 94
#11
Re: No compression on cyl 4. working on dianosis, want input
do you have access to a compressor? remove the schrader valve from the spark plug fitting of your compression tester. put cylinder #4 at TDC (all valves closed). remover radiator cap and oil cap. thread your compression tester hose into #4 cylinder and connect air to it (<100 psi). you'll be able to hear where you are losing compression from- intake, exhaust, crankcase, cooling system....
#12
Re: No compression on cyl 4. working on dianosis, want input
^^that's a nice little home made leak down tester right there. even though it doesn't gauge percentage lost, will still help pin point
#14
Re: No compression on cyl 4. working on dianosis, want input
yea, i was thinking that too. but because of the angle on the air blower, i thought maybe it would be hard to get down in the spark plug tube. but i guess it would fit.
or could just use a straight tip nozzle lol
#15
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Re: No compression on cyl 4. working on dianosis, want input
am i really in a thread where people are suggesting a leak down in a cylinder reading zero?
guys
there is no pressure to leak down!
based on what the op has said a bent valve seems the most likely. the head has to come off at any rate and then you will know for sure
hooking an air compressor to the adapter part of your compression tester will absolutely tell you where the hole is though. with the valve cover off, make sure the cylinder you're testing has all 4 valves closed...meaning the lobe is off them. then, add air and see where it hisses.
guys
there is no pressure to leak down!
based on what the op has said a bent valve seems the most likely. the head has to come off at any rate and then you will know for sure
hooking an air compressor to the adapter part of your compression tester will absolutely tell you where the hole is though. with the valve cover off, make sure the cylinder you're testing has all 4 valves closed...meaning the lobe is off them. then, add air and see where it hisses.
#16
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Re: No compression on cyl 4. working on dianosis, want input
^^Pull the head. Sitting there playing a guessing game is a time waster. No need to run other tests when one is already indicating possible catastrophic failure.
#17
Re: No compression on cyl 4. working on dianosis, want input
am i really in a thread where people are suggesting a leak down in a cylinder reading zero?
guys
there is no pressure to leak down!
based on what the op has said a bent valve seems the most likely. the head has to come off at any rate and then you will know for sure
hooking an air compressor to the adapter part of your compression tester will absolutely tell you where the hole is though. with the valve cover off, make sure the cylinder you're testing has all 4 valves closed...meaning the lobe is off them. then, add air and see where it hisses.
guys
there is no pressure to leak down!
based on what the op has said a bent valve seems the most likely. the head has to come off at any rate and then you will know for sure
hooking an air compressor to the adapter part of your compression tester will absolutely tell you where the hole is though. with the valve cover off, make sure the cylinder you're testing has all 4 valves closed...meaning the lobe is off them. then, add air and see where it hisses.
not sure how you figured bent valve(s) when he has intake charge puffing out the dip stick tube. that would point to a damaged piston or rings. possibly a broken ring land.
#18
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Re: No compression on cyl 4. working on dianosis, want input
valves are what usually go. it's somewhat hard to take out a piston this way but it can be done. the air compressor in a cylinder will tell you where the leak is. there's simply no need to guess
still LOL'ing at people suggesting a leakdown after zero compression has been stated.....think that one out people
still LOL'ing at people suggesting a leakdown after zero compression has been stated.....think that one out people
#19
Re: No compression on cyl 4. working on dianosis, want input
but just for the record here, myself personally, i would have pulled the head off immediately without a second thought. out of curiosity, as well as the repair, of course
Last edited by el crapitan; 02-11-2012 at 01:36 PM.
#20
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Re: No compression on cyl 4. working on dianosis, want input
Ditto the above,^^^ it is a quick easy way to show a customer that something is very wrong, "see sir, the only way the water would be bubbling in the rad is if you have a blown head gasket".
I don't care how long it takes to "leak down" or how much, just where it is going or even just the fact that it is going, I am in a better position to quote the customer whht it will cost to fix.94
I don't care how long it takes to "leak down" or how much, just where it is going or even just the fact that it is going, I am in a better position to quote the customer whht it will cost to fix.94
#21
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Re: No compression on cyl 4. working on dianosis, want input
i want pix when you take it apart if you look at my post I have about Bad compression in my 91 Teg with B18C1 swap you can see the burnt valves i had. also not knowing how long you have had the car if you have low compression already (more the 15 PSI deferance between highest and lowest reading) I would just pull the whole thing out a do a Rebiuld on it. if not atleast rering it while your there it's not that much work to rering the motor with the head off pluse you can look at the rod bearings and if any of them have copper showing you know your mains will not be to far behind.
https://honda-tech.com/forums/acura-integra-6/95-b18c1-weak-compression-3018510/
https://honda-tech.com/forums/acura-integra-6/95-b18c1-weak-compression-3018510/
Last edited by Solster; 02-12-2012 at 12:04 AM. Reason: Add link
#22
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Re: No compression on cyl 4. working on dianosis, want input
Yeah. This is gonna be fun. Been driving a silverado around, with all of its gas guzzling glory. we got our first real snow a few days ago so pulling the head off hasnt been something ive rushed to do. all the tools etc are at my parents house so ima get it over there then start taking it off, just gotta wait for it to warm up a bit. i got everything i need HERE but the workspace isnt ideal and on the off chance i DONT have something i need, my dad has almost every tool i could ever need.
ill actually move it tomorrow and probably blow some air into it with the vc off since i dont have a compressor here.
ill post pics once i have the head off.
this is annoying because i was planning on doing some minor repairs then getting rid of this car in the spring.
ill actually move it tomorrow and probably blow some air into it with the vc off since i dont have a compressor here.
ill post pics once i have the head off.
this is annoying because i was planning on doing some minor repairs then getting rid of this car in the spring.
#23
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Re: No compression on cyl 4. working on dianosis, want input
snow melted. should be taking to a garage tomorrow.
looking at trading it for a white LS 4 door locally once i get this fixed unless anyone knows of a 4 door that someone would be interested in trading for this. should have a fresh headgasket, new rings and fixed valvetrain once this is all done, im kinda going off solsters thread. it makes sense to just do what he did since its not much more and i wanna get rid of it. either way this car and me are ending our relationship soon.
looking at trading it for a white LS 4 door locally once i get this fixed unless anyone knows of a 4 door that someone would be interested in trading for this. should have a fresh headgasket, new rings and fixed valvetrain once this is all done, im kinda going off solsters thread. it makes sense to just do what he did since its not much more and i wanna get rid of it. either way this car and me are ending our relationship soon.
#24
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Re: No compression on cyl 4. working on dianosis, want input
man there is a lot of talk here sheesh.....a bent valve or something of that nature....you would think that there would have been some kind of valve noise...interference engines tend to tell you what is wrong...the timing was off a tooth, i put everything to TDC, and it ran great..i also did the compression test....i am still thinking a piston/ring issue....ill be helping him take the head off here soon
#25
Re: No compression on cyl 4. working on dianosis, want input
You could just take your header off, put cyl 4 at TDC, and poke in with a flashlight. You should be able to see a burnt or bent valve if you are lucky.
Ive also done this before, be careful when driving around on 3 cylinders. I did it in my DA for a while and I swear to god I destroyed my cat with all the gas I was pouring down the cylinder.
Pop the valve cover off and do a valve lash just in case. If you are extremely out of spec, that will tell you something (if you are still curious).
A very high gap spec on an exhaust valve would cause it not to seat properly, and it won't be able to dissipate heat (burnt valve). Maybe a valve lash can bring your compression back
Not sure if really bad valve specs could cause 0 compression? Someone should chime in
Ive also done this before, be careful when driving around on 3 cylinders. I did it in my DA for a while and I swear to god I destroyed my cat with all the gas I was pouring down the cylinder.
Pop the valve cover off and do a valve lash just in case. If you are extremely out of spec, that will tell you something (if you are still curious).
A very high gap spec on an exhaust valve would cause it not to seat properly, and it won't be able to dissipate heat (burnt valve). Maybe a valve lash can bring your compression back
Not sure if really bad valve specs could cause 0 compression? Someone should chime in