What causes 1 fouled plug?
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What causes 1 fouled plug? Help me Please
Alright..
Here's the situation. I installed H/C.. I went to the track and sorta mis-shifted 1-2-3- 2... I caught it pretty quickly though. Got a blinking SES...
Pulled the plugs and only the #5 plug was bad. I changed the plugs. The SES light seems to only blink very seldomly and only at idle for 5 flashes and then it's just steady like it normally is.
I told the guy that was gonna tune my car about the #5 fouled plug, and he said that I may have damaged the valve seal or something on that cylinder.
Anyone else have a similar problem to this. Could a bent rod cause this also?
Thanks..
Here's the situation. I installed H/C.. I went to the track and sorta mis-shifted 1-2-3- 2... I caught it pretty quickly though. Got a blinking SES...
Pulled the plugs and only the #5 plug was bad. I changed the plugs. The SES light seems to only blink very seldomly and only at idle for 5 flashes and then it's just steady like it normally is.
I told the guy that was gonna tune my car about the #5 fouled plug, and he said that I may have damaged the valve seal or something on that cylinder.
Anyone else have a similar problem to this. Could a bent rod cause this also?
Thanks..
Last edited by Z28Venom; 04-22-2004 at 08:58 PM.
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Update
Alright..
I went down.. Pulled all of my pushrods to see if I bent any. None were bent (shrewwwww) thank goodness.
However, I changed my plugs on Sunday.. It is now Wed. and the same #5 plug is completely covered with some kind of soot. Not oil or gas, kinda like a thick black powder. I only start the car to let it idle and I took a 20 min drive on Mon.
I'm totally lost. Also the SES light only blinks at idle.
Could it be that my car just needs a tune. I've installed LT's, removed the cats, and done a h/c swap. I'm hoping that this is all that it is, but it just seems weird that it's only fouling one plug.
I also tried the feeling the header from that cylinder on startup to see if it was firing, and yes. It got hot quick as hell..
Any more ideas?
I went down.. Pulled all of my pushrods to see if I bent any. None were bent (shrewwwww) thank goodness.
However, I changed my plugs on Sunday.. It is now Wed. and the same #5 plug is completely covered with some kind of soot. Not oil or gas, kinda like a thick black powder. I only start the car to let it idle and I took a 20 min drive on Mon.
I'm totally lost. Also the SES light only blinks at idle.
Could it be that my car just needs a tune. I've installed LT's, removed the cats, and done a h/c swap. I'm hoping that this is all that it is, but it just seems weird that it's only fouling one plug.
I also tried the feeling the header from that cylinder on startup to see if it was firing, and yes. It got hot quick as hell..
Any more ideas?
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Originally Posted by 2xLS1
Run a compression test on that cylinder and compare it to a couple of good cylinders for starters. Did you put in hardened push rods with the H/C swap? If so, you may have slightly bent a valve on that cylinder when you did the misshift.
Just a quick question? Can you bend valves and not bend a pushrod?
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Originally Posted by Mark Campbell
Could be a slight leak in an injector. Those are tight tolerance pieces and a little leak could cause a problem at idle and still not cause a problem above idle!
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Originally Posted by AsianIce25
Agreed, could be an injector, but i doubt it. They dont go bad very often, but they can. Did you ever do the pcv mod? Make sure all the wires are on all the way, and those gaps looked really big. whats your gap at? I think stock on mine was .065 or .055, but theyre at .034 right now. What kind of plugs? a colder plug will take longer to reach self-cleaning temperature than a stock plug. but that looks like oil to me...
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After my h/c swap, I just continued to use my Mobil 1 synthetic oil. Could this have caused the valves seals or something to not settle properly. I'm just thinking of a lot of crap. The compression check is getting done tomorrow morning.
Still tryin to get this question answered. Can you bend a valve on a bad shift and not bend a pushrod.
Also how accurate is the rolling the pushrod on glass to verify whether or not it's bent?
Thanks
Still tryin to get this question answered. Can you bend a valve on a bad shift and not bend a pushrod.
Also how accurate is the rolling the pushrod on glass to verify whether or not it's bent?
Thanks
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Originally Posted by Z28Venom
When I did the swap, I used new stock pushrods. I knew that I would eventually screw up and shift. And it would be alot easier to change pushrods than valves.
Just a quick question? Can you bend valves and not bend a pushrod?
Just a quick question? Can you bend valves and not bend a pushrod?
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Originally Posted by blkbeaZ28
So you used stock push rods instead of hardened ones?
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Originally Posted by Z28Venom
I was told that the pushrods were the weak link. And if I miss shifted like I've done, then the rods would bend and not the valves. The last thing I want to do is to remove the heads to replace valves. So I used new stock pushrods on the new heads.
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Originally Posted by AsianIce25
The pushrods are the weak link, but that doesnt necessarily mean that they will ALWAYS bend before the valves, it just means most of the time they will. Anyways, id tighten the gap on your plugs to at least .050 if I were you. Then pull the intake bellow, maf, and lid off so you can get direct access to your throttle body. open the plate up and take a look inside with a flashlight. Id take a look and see if theres any oil inside. If there appears to be a lot id do the pcv mod and get a 2002 Z06 PCV valve from a dealer, usually like 3 bucks. if you look at the new pcv valve, theres no valve at all, just a lil (~1-2mm) hole in the end of it. it reacts a lot faster. keep the oil out of your car. then maybe run some top end cleaner though that bitcH. Why are you running tr6's? for juice? if so, gap them real small, like i said, mine are at .034.
So this is what I need to do this afternoon.
1)Run Compression Check on #5 Cylinder
2)Check PCV Valve
3)Move #5 injector to #3 Injector
What do you think the chances are that I have a shot ring or damage piston on that cylinder? If that's the case, how hard is it to pull a piston?
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Originally Posted by Z28Venom
I was running TR6's because I was getting ready for the juice. Now I'm gonna have to run NGK TR5's until the TR55's that I ordered get here.
So this is what I need to do this afternoon.
1)Run Compression Check on #5 Cylinder
2)Check PCV Valve
3)Move #5 injector to #3 Injector
What do you think the chances are that I have a shot ring or damage piston on that cylinder? If that's the case, how hard is it to pull a piston?
So this is what I need to do this afternoon.
1)Run Compression Check on #5 Cylinder
2)Check PCV Valve
3)Move #5 injector to #3 Injector
What do you think the chances are that I have a shot ring or damage piston on that cylinder? If that's the case, how hard is it to pull a piston?
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I would rule out PCV-based oil consumption or all plugs would be fouled. We know the cylinder is firing, so there is either oil being sucked down the valve guide, or through bad rings, or the injector is stuck open.
Compression test will tell you if there is a problem with rings or valve. Switching injectors will tell you if it's the injector. If neither of those 2 tests shed any light I'd settle on the valve seal.
To answer your question you can bend a valve without bending a push rod. In fact, I don't think you can bend a pushrod without bending a valve IF THE PISTON CONTACTED THE VALVE. Most of the time you bend a pushrod it's from simple valve float. The pushrod comes off the lifter or the lifter comes off the cam and when they meet up again, the lifter is coming up while the rod is coming down and you bend your pushrod...this is NOT due to valve hitting the piston or you WOULD see a bent valve also.
Good luck figuring out your problem.
Compression test will tell you if there is a problem with rings or valve. Switching injectors will tell you if it's the injector. If neither of those 2 tests shed any light I'd settle on the valve seal.
To answer your question you can bend a valve without bending a push rod. In fact, I don't think you can bend a pushrod without bending a valve IF THE PISTON CONTACTED THE VALVE. Most of the time you bend a pushrod it's from simple valve float. The pushrod comes off the lifter or the lifter comes off the cam and when they meet up again, the lifter is coming up while the rod is coming down and you bend your pushrod...this is NOT due to valve hitting the piston or you WOULD see a bent valve also.
Good luck figuring out your problem.