Engine miss firing 1 cyl

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Cars been great and running for a while but on sat night i took it out and we were parking up in a car park behind this bar i must of put 10% throttle on to get around someone and all of a sudden the car car starts miss firing but only on idle when i would rev it or drive it would be fine. So i thought it would just be ignition lead just not connecting to the dizzy 100% or something like that but on the way home on the freeway i thought i would give it a little squirt and see what happens. dropped it back from 5th to 3rd and put the foot down and then 1 cylinder just stopped firing completely. I managed to drive it home.

So far ive taken the plugs out and they were carbonized a fair amount so i cleaned them off with a wire brush on my bench grinder and made them look like new. Put them back in and still 1 cyl is miss firing.

In the arvo im going to grab some more plugs so i can rule out them completely but what else should i check? I got Top gun 10mm ignition leads which look still in good condition but with a volt meter is there any way i can check they are running 100%? I know u can get those crimper type volt meters that u just clamp onto the ignition wire whilst its running and it tells you specifics but i dont have that so i need to fine a way to make sure they are all in good cond.

Cant be dizzy rotor cos i had that go on me like 5,000km's ago so ive replaced that with a new one.

Any other idea's?

[TODA AU]

10k ohms per foot is ok for leads...

To determine missfire, start with a compression test.
If fail, do a leak down, determine fault (Top or bottom end)
If pass...
Use a noid light to test injector wireing, check spark, engine earths etc
Pressure test cooling system if no results above*
If you have access to a borescope, inspect the cylinder (inside via spark plug hole)

Also use the blue magic liquid to test cooling system

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Ok so i got new sparks, installed them and still got the same issue. After that i removed the sparks to do a compression test and realized the far right cylinder which i think is number 4 wasnt firing properly as the spark plug wasnt being used.

I did a compression tests on all 4 cylinders and these are the results below.

1 2 3 4

170psi 170psi 162psi 0psi

Thats in order from left to right with number 1 closest to the dizzy.

Ok so 4th cyl has the issue. I figure its top end e.g bent valve but ill do a leak down test anyways.

Toda can you explain how to do a leak down test pls?

[TODA AU]

The cylinders are numbered right to left...
So 4, 3, 2, 1
# 1 is the closest to the front of the engine which is the cam belt end...
Anyway, I digressed.

Re leakdown, do you have a leak down tester & compressed air available?
(I'm guessing you're at home so I'll move on to a DIY technique)
Get an oil can (with clean engine oil in it) & squirt approx 3~4 squirts down # 1 spark plug hole
Now repeat the compression test within a minute.
if the compression increases significantly, your rings/ring lands are gone.
No change is in the head or a hole in the piston.
Head issues are usually valve related, be that bent or burnt out.

If you can't figure it out, just double check the valve clearences.
If they are all correct, the head will have to come off anyway so the leakdown is really just accademic.
Once the head is off, the problem should be apparent.
Hope that helps

Cheers

[fatboyz39]

0 psi.. OH NO...

So what did you do? Over rev it?

[FastFwd]

0 psi.. OH NO...

So what did you do? Over rev it?

Nah man that's the thing. I was in a car park and i was trying to get around someone...probably doing 20k's max and i must of had it on around 3000-3500rpm max also and as soon as i let go of the throttle it felt like 1 ignition wire kicked off the motor cos ive had that happen to me in the passed. So i opened the bonnet checked the wires started it back up and still same issue. So i thought meh its prolly something small so i went into the bar for some drinks with my gf and freinds. Came back at the end of the night and when i would drive the car like under load all 4 cyl would be working. but when on idle it would kick back to 3 cyl. So i figured its nothing bad must be a fouled plug or something and it probably was that to begin with but i got onto the freeway and i thought maybe cos its rich i could clear it out with a bit of a squirt and went from 5th to 3rd and as soon as i put my foot down at around 5500rpm-6000rpm it just shat itself. After that i drove it home with only 3 cylinders running. I dont know if it was a combo of maybe the timing was off somehow, maybe one of my toda cam gets came loose a little and that was the idle issue and then afterward me giving it hurts just ruined it. Dunno but yeah number 1 cylinder isnt looking to good.

[FastFwd]

The cylinders are numbered right to left...
So 4, 3, 2, 1
# 1 is the closest to the front of the engine which is the cam belt end...
Anyway, I digressed.

Re leakdown, do you have a leak down tester & compressed air available?
(I'm guessing you're at home so I'll move on to a DIY technique)
Get an oil can (with clean engine oil in it) & squirt approx 3~4 squirts down # 1 spark plug hole
Now repeat the compression test within a minute.
if the compression increases significantly, your rings/ring lands are gone.
No change is in the head or a hole in the piston.
Head issues are usually valve related, be that bent or burnt out.

If you can't figure it out, just double check the valve clearences.
If they are all correct, the head will have to come off anyway so the leakdown is really just accademic.
Once the head is off, the problem should be apparent.
Hope that helps

Cheers

Ahh yep i know that test, i didnt know it was called a leak down test but ill give it a shot either way. I have a strong feeling its bent my exhaust value on the #1 cylinder. I removed the plug from that cyl and started the car and smoke was coming out from the plug hole so i gathered the exhaust value is stuck open. Could be wrong tho, and i dont think its rings either as the motors only had 5,000kms max since i last rebuilt her and its been running perfect since. Either way i gotta take off the head if its top or bottom end.

Ive never replaced my valves, much to it? ill be doing all the work myself and getting parts wholesale but will i be looking at replacing the single bent valve? or is it something that if you bend 1 you buy a whole set? how much you think something like this will set me back if im doing all the work myself?

[TODA AU]

Ive never replaced my valves, much to it? ill be doing all the work myself and getting parts wholesale but will i be looking at replacing the single bent valve? or is it something that if you bend 1 you buy a whole set? how much you think something like this will set me back if im doing all the work myself?

You only need to replace what is bent/burnt. The rest can be just checked... But if 1 exhasut valve is bent, chances are it's not the only one.
Valve cost off the top of my head is approx $30 per valve, that's aftermarket & OEM (Some US products are pretty good value at the moment - Supertech)
You'll need a VRS (upper engine gakset) kit as a minimum + once you've pulled it down, the valves or seats or whatever else may be stuffed.
Cyl head overhaul cost varies depending on how it's done... STD overhaul with 3 angle seats is approx $350 / CNC overhaul with 5~7 angle seats from $550

[lil_foy]

Adrian i'm never short of amazed at the free information you throw out there, kudos to you mate.

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You only need to replace what is bent/burnt. The rest can be just checked... But if 1 exhasut valve is bent, chances are it's not the only one.
Valve cost off the top of my head is approx $30 per valve, that's aftermarket & OEM (Some US products are pretty good value at the moment - Supertech)
You'll need a VRS (upper engine gakset) kit as a minimum + once you've pulled it down, the valves or seats or whatever else may be stuffed.
Cyl head overhaul cost varies depending on how it's done... STD overhaul with 3 angle seats is approx $350 / CNC overhaul with 5~7 angle seats from $550

Cheers for the info man. Much appreciated

Seeing as that ive had issues with my current head in the past. Minor things just stripped bolts on the cam caps and few other things i might see if i can buy a full head and just replace my cams and cam gears with it. Searching on here people are buying complete heads for around 300-500

again thanks for the info

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honda wrecker here in perth can do me a complete head without cams and cam gears for $350. Ill simmer on the idea for now...

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Complete head for $150 with 70,000kms on it. Its B16a Japspec head

http://imgur.com/bObMM.jpg

My current head is b16a2 japspec. I been told theres a difference in valve springs on the b16a2 to the b16a is that right? dual intake spring on the b16a2 and single spring for the b16a?

If theres no difference then i can just work and rebuild this current head and when im ready ill just replace heads. Ive currently got toda cams and cam gears which i can swap over also once the new head is on