Plug reading
- Thread starter LakeAnna
- Start date
allimax
Active Member
What's the NGK part # on that? It looks iridium or platinum. Yours is a "X" motor and maybe they run those on the newer 2.5's. You got me curios.
Look at it this way... if you toast it that gives you another reason to get a 280.
whipper
Well-Known Member
X2 on the money for every day use. Is that the leanest hole or richest hole? If thats the lean hole then great. You have to run wot then chop the power and coast to a rest then pull the plugs to get the best reading. if your motor is running after wot then you will wash the plug a little and you wont be getting a true color. Tanned is great. The dark spot is rich. White is boom.:big grin i used a heat gun to determine my hottest hole and coolest. Ussually the one furthest away in the cooling is hottest. I made the lean hole light tan and the rest tanned. Takes for ever and alot of testing get it just right but that plug looks real great. Are you testing an adjustable ACU or just checking? I was playing around with my acu adding fuel at different rpm,s when i was testing and plug reading. If they looked like yours at wot then thats golden.
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Hey James, I was not really planning on doing a plug reading per say. Before I put it on the trailer I nailed it from a 20 mph roll for about 800 feet. It idled in gear maybe 10-15 seconds or so to help get to the trailer.
I was having the injectors cleaned and checked out so after learning that almost all of them where going lean I decided to take a look.:confused
That plug in the picture is out of #6. All of the plugs in it look pretty much the same less the new one in #1 which I replaced after it fouling earlier this spring. I only ran the motor a couple miles so the new plug is still really clean.
I had the pcu done at Simon last year and he raised the limiter and did the flywheel at the same time. I think since the limiter is bumped up the fuel delivery was raised in the upper rpm range too(would seem reasonable to me??). I called but he is out until Monday. I'm not sure if the fuel curve was changed on not... waiting to hear back from Simon.
Trying to hold the chances of "BOOM" to a minimum whenever possible...
I was having the injectors cleaned and checked out so after learning that almost all of them where going lean I decided to take a look.:confused
That plug in the picture is out of #6. All of the plugs in it look pretty much the same less the new one in #1 which I replaced after it fouling earlier this spring. I only ran the motor a couple miles so the new plug is still really clean.
I had the pcu done at Simon last year and he raised the limiter and did the flywheel at the same time. I think since the limiter is bumped up the fuel delivery was raised in the upper rpm range too(would seem reasonable to me??). I called but he is out until Monday. I'm not sure if the fuel curve was changed on not... waiting to hear back from Simon.
Trying to hold the chances of "BOOM" to a minimum whenever possible...
whipper
Well-Known Member
Chris sounds like you have a nice motor combo. I remmeber when I was trying to set up the acu from Brucato for fuel dilivery at differant rpms useing plug reads as my guide and seat of pants. What a PITA.:big grin Theres a thread on hear about that. I went threw 10 sets of plugs because i didnt want to use the same plug for differant settings incase it was fouled from being to rich or lean from elier tests. i can only say a Pyro would have come in very handy at the time. I dont touch nothing now since so i DONT HAVE TO GO THREW THAT AGAIN!! :help Jay and Gary helped me alot threw the plug read thing. WOT chop or just pull the kill swith. Thats the best way just have to be carfull. i would run to round 80 and kill it. Kinda freeky the first time because you wonder if she will hook or not. Never a hint of any thing bad.
I should probably send a set of injectors for cleaning. i have a spare set Ive been meaning to send out.
I should probably send a set of injectors for cleaning. i have a spare set Ive been meaning to send out.
SLOmofo
Well-Known Member
" Before I put it on the trailer I nailed it from a 20 mph roll for about 800 feet. It idled in gear maybe 10-15 seconds or so to help get to the trailer. "
Not going to get it, with the second sentence......... Better would be to pull the kill lanyard and pucker. Then pop the cowl off and pull all the plugs. Then go longer and longer.
The longer you go the tighter the pucker!
I'm too old to pucker, so mine are always fouled. Then they go for a swim.
Not going to get it, with the second sentence......... Better would be to pull the kill lanyard and pucker. Then pop the cowl off and pull all the plugs. Then go longer and longer.
The longer you go the tighter the pucker!
I'm too old to pucker, so mine are always fouled. Then they go for a swim.
Well put it back together with fresh injectors, lines and filters and it fouled 1 then 2 and finally the 3rd plug was black and misfiring by the time we got to a dock. Put 3 more in it and it runs great again.... wtf. (it ran fine for about 2-3 hours on a couple different trips before this.)
Bpr8eix is what I been running. I know a few others have had issues with the x fouling plugs. What to do is the question.
Bpr8eix is what I been running. I know a few others have had issues with the x fouling plugs. What to do is the question.
I wonder if could have anything to do with the other sensors? There is a temp sensor and MAP sensor in the intake. The book shows the values for the temp sensor if you want to pull it and check the ohms.
If a sensor fails the motor will still run but will go pig rich because the computer then defaults to 32 degrees. (Something like that, I'll have to reread the manual.)
If a sensor fails the motor will still run but will go pig rich because the computer then defaults to 32 degrees. (Something like that, I'll have to reread the manual.)
SLOmofo
Well-Known Member
Is it the same cylinders that foul? Were all the plugs new and then you ran it.
I'd run it so all cylinders are firing , then change to new plugs. Use something equivalent but cheaper for now. Then run it, and check the plugs. Fouled or slightly fouled plugs won't tell you anything, but that it isn't running correctly!
One thing I do is pull the plug wire off/back so there is a gap between the wire end and the plug. What this does is increases the required voltage to rise = hotter spark. Now this spark has to jump across the gap from wire to plug. This sometimes will clear the fouled plug for the time being. Other wise the voltage that is applied to a fouled plug only will build to what is required to travel down the fouled area.
A coil only will supply what is necessary to travel to ground. If that requirement is more than the coil can put out spark doesn't take place. If the spark can find an easer path, that's the one it will take. Don't be that path! <;-)
I'd run it so all cylinders are firing , then change to new plugs. Use something equivalent but cheaper for now. Then run it, and check the plugs. Fouled or slightly fouled plugs won't tell you anything, but that it isn't running correctly!
One thing I do is pull the plug wire off/back so there is a gap between the wire end and the plug. What this does is increases the required voltage to rise = hotter spark. Now this spark has to jump across the gap from wire to plug. This sometimes will clear the fouled plug for the time being. Other wise the voltage that is applied to a fouled plug only will build to what is required to travel down the fouled area.
A coil only will supply what is necessary to travel to ground. If that requirement is more than the coil can put out spark doesn't take place. If the spark can find an easer path, that's the one it will take. Don't be that path! <;-)
fnshrmaster
Active Member
That sucks Chris, I hope you get that squared away. Let us know what you figure out.
SLOmofo
Well-Known Member
This is good info. Temp sensors can and will fail at certain temperatures. The way to find them is use a Graphing multi meter. One that will display the signal over time so you can see it when it goes bad/glitches. They will some times glitch for a split second and won't be seen on a normal meter. You could use a meter that has a Min/Max capability. Also you could use the correct OHM resistor (for normal running temp) in place of the sensor. A wire harness that shorts to ground or opens the circuit can also be the problem.
Map (manifold Absolute Pressure) sensors are best > Try Known Good.
Gary it has fouled different holes each time. Lets see... first this spring it fouled #1 and then I pulled it apart later and did the injectors, reeds and lines etc. So, I had 5 older plugs with maybe 30-40 hours on them and 1 new one in #1.
Today it ran fine and as we where going to plane I noticed it had dropped a cylinder and was misfiring. It got worse as I babied it for about a mile to the dock. Pulled em and 3 plugs looked like carbon foul and wet. None was the original hole from the spring.
Gary I was typing while you had already posted... What about the map sensor???
Today it ran fine and as we where going to plane I noticed it had dropped a cylinder and was misfiring. It got worse as I babied it for about a mile to the dock. Pulled em and 3 plugs looked like carbon foul and wet. None was the original hole from the spring.
Gary I was typing while you had already posted... What about the map sensor???
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