compresssion results


shooter mcgavan

shooter mcgavan

98 ek9
Joined
Sep 12, 2008
Messages
1,150
well.i did a compression test on my ek9 came out with 190psi on all 4 cylinders.would this be regarded as good,ok or rebuild time.thanks!
 
all 4 190? if so your doing ok. your gonna get people that say they get 200, 220, 230 across the board. i would worry about everyone elses #'s cause everybody uses a different compression tester. my snap on reads 205 on my jdm itr and a **** tester from the auto parts store on the same motor and it read 225 across. as long as your 4 cylinders are close your motors is running healthy and obviously your compression #'s vary with what psitons u have.
 
agreed, the tighter you screw it in the better the result you get - the fact that they are even is a good sign

why did you compression check it? are you losing oil?
 
no its not burning oil i just think it seems a bit sluggish so wanted to start testing the more serious things first.its down about 15horses according to dyna pack!(158bhp).he reckons decent 9 makes 175 on it. also it eats petrol and seems dead before the vtec.now im gonna replace 02 sensor and its missing the odd time when hot so ht leads are probably banjod also but 02 sensor dont effevt power does it?
 
O2 can affect power most definitely. Missing can also be as you said your ht leads, but also your cap/rotor on the distributor.

Have you adjusted the valves?
 
shooter mcgavan said:
no its not burning oil i just think it seems a bit sluggish so wanted to start testing the more serious things first.its down about 15horses according to dyna pack!(158bhp).he reckons decent 9 makes 175 on it. also it eats petrol and seems dead before the vtec.now im gonna replace 02 sensor and its missing the odd time when hot so ht leads are probably banjod also but 02 sensor dont effevt power does it?
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your saying your car has a slight miss after the car has been warmed up? it misses at idle? missing when your partial throttle? full throttle? how long has this been going on? check engine lights? u have a leak down tester or know someone with one cause that will 100% tell u if u have a internal problem. sounds like a bad coil, ignitor, or bent valves. more like bent valves if your car doesnt miss fire when its cold.
i need more info to give u a good respose.
 
190 psi hmmmm what compression meter/tester do you used?
 
comp tester not sure on brand but was 50 euros so cant be the worst!!ive replaced the dizzy cap and rotor.reason i think ht leads is because it misses worse when wet i think they arc off the head if you get me.at first it only hiccuped on partial throtle once,now on full throttle it does as well and worse than before and only below 3k rpm.i havent done valve clearance yet.i dont have a leak down tester however!
 
change your coil and ignitor. u ever come across a leak down tester grab one cause there's very useful to have when u think u have engine problems. can tell if u have bent intake or exhaust valves, bad head gasket, bad rings.
 
^^i presume these are inside the distributor?whats involved in changing them.appreciate everyones help.
 
Try changing your fuel filter? Also worth checking your timing and timing belt seen a sir down on power before was timing belt not been fitted correctly was off by 2 teeth
 
2teeth!wow thought that would have been enough to cause interference.fuel filter i havent done,looks fresh but no harm to change it.
 
It didnt cause interference but it was seriously down on power
 
shooter mcgavan said:
^^i presume these are inside the distributor?whats involved in changing them.appreciate everyones help.
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If you have a friend local to you with a healthy EK9 willing to swap out the distributor with you that would help diagnose the issue quickly.

Just ensure that the car is OBD2, twin cam vtec. Otherwise, the coil/ignitor is not too hard to replace.

Also, are any grounding cables missing? If they're all there, have you tried cleaning them and giving them a fresh grounding point? It wouldn't hurt to have them replaced either. They can be made up quite easily or purchasing aftermarket ones are also good if you have the means.
 
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RagingAngel said:
If you have a friend local to you with a healthy EK9 willing to swap out the distributor with you that would help diagnose the issue quickly.

Just ensure that the car is OBD2, twin cam vtec. Otherwise, the coil/ignitor is not too hard to replace.

Also, are any grounding cables missing? If they're all there, have you tried cleaning them and giving them a fresh grounding point? It wouldn't hurt to have them replaced either. They can be made up quite easily or purchasing aftermarket ones are also good if you have the means.
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so if i just get an earth kit will this do the job?i can get a dizzy out of a 96 dc2 but not sureif there the same.im thinkin now ots not dizzy as i got nology plug leads today and this has sorted the misfire problem!:clap:something went right for me!not too sure if power has improved fully
 
It sounds to me the culprit all along was your grounding cables. I'm willing to bet that if the nology wires solved the misfiring it's due to some pretty extreme corrosion on your grounds.

I'm all for spending money on the car, but start with the basics and clean all your grounds first before getting an aftermarket grounding system. After you've cleaned them, put your stock plug leads back on and see if it the misfiring reoccurs.

I've seen the missing grounds, severely corroded grounds (generally on the thermostat housing) cause the misfiring problems you've described - with owners going absolutely insane replacing almost everything short of the motor to get it fixed without paying attention to the built up corrosion/missing grounds.
 
RagingAngel said:
It sounds to me the culprit all along was your grounding cables. I'm willing to bet that if the nology wires solved the misfiring it's due to some pretty extreme corrosion on your grounds.

I'm all for spending money on the car, but start with the basics and clean all your grounds first before getting an aftermarket grounding system. After you've cleaned them, put your stock plug leads back on and see if it the misfiring reoccurs.

I've seen the missing grounds, severely corroded grounds (generally on the thermostat housing) cause the misfiring problems you've described - with owners going absolutely insane replacing almost everything short of the motor to get it fixed without paying attention to the built up corrosion/missing grounds.
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but could poor grounds be responsible for the lack of horse power which was the more concerning problem!!i will do as you have advised and give them a good going over.
i also put a diagnostic tool on it and as i was scanning the values i noticed the o2 sensor works between 0 and 0.4 volts.is this ok?also the map sensor value was increasing instead of decreasing when i floored the throttle.would i be safe in assuming the map sensor is faulty(ive no vacuum leaks)?
 
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