bad valves/seals etc?

reason im asking is my car misses on 1 cylinder.iv changed everything..and each time i change it, it hink YES ic fixed it and its normally ok for a week or so then all of a sudden it starts missing again.

list of things i havge changed, in order:

spark plugs
leads
dizzy
fuel injector (for the cylinder tht was missing)
then ECU!

checked impulse to injectors...even when its missing....that cylinder is STILL getting a signal to the injector.both power and an earth etc.

the mechanic/electrican said next best bet is try changing the injector again (just incase, but i think my old injector was actually fine too!)

(and all the old bits like dizzy ecu plugs were fine too!

i recently put a new engine in the car and before this all ancillaries were fine.

i changed the knock sensor because it was broken (the garage broke it but decided not to tell me)..when i changed it..the car ran fine for 2 weeks then AGAIN....started sounding like an impreza....

and its the cylinder closest to the dizzy.

when it missfires..sometime when i pull the injector plug off...it makes no difference....which would point to a dodgy injector( whyat r the chance sof having 2 dodgy injectors) (altho second 1 was second hand!?)

im gna swap over the injector with 1 from different cylinder tonight and see what happens.

iv tightened the clip to the plug too...but il change that too i guess!

but to be honest i think/know/feel its the engine.

the head is noisey and im thinking maybe valve clearance? do hydrualic valves in the b18c-4 have a clearance?

what could be the problem that what cause it to run ok sometimes...then really bad sometimes?

saying all this in terms of power the car has plenty.no engine codes etc either.

just a boggy cylinder that decides to start misfiring sometimes.

exhaust smoke comes outs in pulses when at idle and misfiring then at the other times when the cars ok comes out free flowing.

any help would be appreciated as im seriously UPSET and havnt slept wondering what can it be!

a compression test showed around the 170 mark (evenly, without the gas pedal fully pressed tho)

have also checked the timing with a timing gun.

 

could be oil leaking into the cylinder....are u valve cover seals good? sometimes when you change sparkplugs oil from around the seals in the tubes can leak down into the cylinder...when you do spark plugs make sure all seals are good...and if it was a machanical problem like a bent/burned valve it would be missing all the time not intermitten....so could be your injector/icm/ rotor inside dizzy and valve do have to be clearance using a feeler gauge with the engine dead cold...

 

wouldnt an oil leak be permanant tho? the seals r ok.the car does eat oil but i cnt say how much.....i top it up a litre every month but more sometimes after hard driving.and i drive hard often! lol.

yes bent burnt valves would be permanent but what about a sticky valve?

icm? is that ecu? if so ive changed that too.dizzy i put a new 1 on,but to be honest i know the first 1 was fine coz it was fine on the other engine.so was the injector and everything else.

i thought its pointless changing all these things but have done so just to 'make sure'.

its defo the engine OR the clip plug for the injector, im gona change that tomorow along with changing the injector AGAIN.but at this stage its bloody pointless!

im gonna swap the injector over to another cylinder....and also get a new plug, snip the wires and connect the new plug on.

it ran fine for almost like a week! when i changed the knock sensor it ran fine...whenever i change something it runs fine!...for a while.

the signal to the injector wires is there and shows up when i attach a small bulb to the end of it....it even goes brighter when i rev it and i also checked the the current etc and it was more or less a rally good solid signal.

earth was present too.

so...its injector....or somethin that changes in that cylinder.

il hope that the second had injector i bought is faulty but i highly doubt it as the 1 already in there was totally fine prior the engine swap.

if i had a leaky headgasket that would not be intermittent either.so it cant be that. (i hate when people just say oh its the head gasket)

i have a water leak some where too but its difficult to get to the bottom of it because its been raining alot here in the uk.tomorow im gonna park the car in a garage and see if i can find it.

all i can think of is stickly valves./bad clearances as the head is abit clickety clackety....but then some times fine.

 

Valves being too tight maybe? Have u checked the valve lash? Worn valve seats can cause the valve lash to get tighter and eventually cause a misfire.

Unplugging the injector and getting no rpm drop doesn't really tell u anything. If that cylinder is misfiring already, it won't matter if u take away the fuel.

 

Valves being too tight maybe? Have u checked the valve lash? Worn valve seats can cause the valve lash to get tighter and eventually cause a misfire.

Unplugging the injector and getting no rpm drop doesn't really tell u anything. If that cylinder is misfiring already, it won't matter if u take away the fuel.

 

i havnt checked the valva lash just yet. it has something to do with water.

i pulled out plug 1 and it has a light brown colour....theres defo water in the mixture.

inlet manifold has a water port on it too.....my guess is...by looking at the gasket area.....the guy has broken the gasket...and has used the liquid/gel/rubber type sealer around that area.

the water port is 2cm away from the air intake hole on the block...so if theres a gasket thats not doing its job properly....water is leaking into the air/fuel mixture when pressure builds up in the coolant system.

the water port is right next to the first cylinder air port (the cylinder closest to dizzy) and thats the chamber thats missing. i....when it starts missing i get white smoke....i think the added water into the fuel chamber is causing a lean mixture hence abit of extra white smoke (condensation) through the exhaust.

does this make sense to any 1?

am gonna change the gasket and see what happens.im losing water..and when i turn the car off....i hear the vacuum...then at the end a burbling sound water/air sound coming from the water port/gasket/intake chamber. so im hoping and WISHING thats the problem and not a headgasket.

for 1 week the car run fine...(the weather was abit warmer then) and when it was running fine i WASNT losing any water.

so by judging the spark plug condition....theres defo water going into the chamber....

any opinions?

(p.s compression test showed 220psi on all cylinders, i think 1 was like 218)

 

is this obd2 or 1....if it's obd2 you have a pick up crank angle sensor mounted to the block behind the crank pully that sends a signal to another senor in the dizzy that have to match for each rotation......

there is also the t.d.c senor and anthor senor in the dizzy (i can't remember the abbrev. for it at the moment) ...........so a total of 3 in the dizzy and the one behind the crank pully, and all four have to read and monitor each other........meaning if ones off or not hooked up or what ever it will throw a misfire code......

 

i put a new dizzy on.even tho i didnt need to.and im not getting any misfire codes anyway.the car doesnt throw any codes.

...its obd2.

i jsut turned the car off and could hear water/steam escaping somewhere near the intake mani...i then loosened the rad cap and loads of steam was escaping from the over fill tank pipe....then there was no water in the radiator either hence the steam/pressure .

i cant wait to have a look at the gasket inside the manifold!

 

well it could of been the old dizzy that you replaced throwing the misfire code and the gasket problem is a separte issue all together.........just thinking out loud.....

so your thinking it's the intake manifold gasket leaking?.....at least it would be a quick fix and nothing major involving tearing the motor apart.....

it sounds like your on the right path...let us know....

 

i just wrote im NOT getting any misfire codes!!?

i could hear pressure escaping from the intake mani..i think it was leaking internal

http://img843.imageshack.us/i/imagephp1010.jpg/

theres a link to a similar manifold..u can see the small water port at the end....i think the pressur/water is leaking through the small gap and into the intake chamber that im getting missing/water fouled spark plug on...it would make sense....

also around that area the guys who installed the head used liquid sealer i can see it its red so theyv broke the original gasket at the end i guess....

i HOPE.lol.

 

That's actually cylinder 4 that you're talking about. Cyl 1 is nearest to the timing belt.

 

hmm thts what i was thinking lol.

 

I've got a similar problem with my 95 honda accord V6

Mine misses intermittently at idle, but only after the car warms up. While driving there is no miss, unless I'm at idle. It seems like the miss is less noticeable and less frequent if I put the car park and just listen to it, almost can't notice it when I did this yesterday.

My tach would also go crazy, so i figured it was the ignition coil. I changed the coil and only the tach got better. I had to take the cap off to get to the coil and I did see some dirt/grit/metal bits in it. I would think if it was a worn rotor or cap it would miss all the time. Any comments?

This has been going on for a while. I used to get a misfire code but I can't remember which one. It went away by itself after being on for months. Maybe the CEL burnt out??? haha I need to check that next time I drive it.

I am just starting to troubleshoot mine. The first thing I'm gonna do is run some fuel injector cleaner through a couple of tanks. I thought mine had a lot of white smoke (from water) so I ran some dry gas through and this seemed to help. Now you got me wandering how water or maybe coolant is getting into my fuel system

-Then I'm gonna unplug O2 sensor and see what happens.
-Inspect and clean EGR valve, I did this a few months back. It seemed to make it a little better at first but didn't hold. I'm not sure if I drove it enough after I thought it fixed it.
-I've got bosch wires and cap, NGK plugs, but I might replace them.

I will continue to see what you are doing and if I figure mine out I will let you know.