Ran rich, then fouled plugs. Cleaned plugs, car exploded!?
11-28-10, 12:12 PM
#1
Ran rich, then fouled plugs. Cleaned plugs, car exploded!?
OK, maybe it didn't explode, although I am tempted to take a match to this car 
Pre-reading cliff notes: Car went leaned and sounded like a gun. I think the plugs are fubar, need more opinions.
Yesterday morning I took the car out. It started good and ran AWESOME. While it was warming up it was pretty rich. It was low 40's I think and it was idling first low 10's
but it warmed up and leaned out a little. It drove great in the 13's and was idling around 12.5. I went out later to tweak my thermowax & idle screws because the idle wasn't always dropping down when fully warmed up, still staying around 1200. So anyway I start the car and it's stupid rich like before. But this time it warms up, but the idle is weak and it's still absurdly rich! It was also pulling a little less vacuum, 15 rather than 19-20 I have normally warming up. I noticed two things. The thermowax wasn't warming up because the coolant line was pinched, and a vacuum cap had fallen off the back of the manifold. Well the thermowax is one issue which I fixed, and then I put a new vacuum cap on. After fixing both the car was getting harder to start and still running too damn rich. At this point after idling and running around low 10's I figured I must have fouled the plugs pretty bad. It got cold and late, so I called it quits.
Now I come out this morning and get to work. I pull the plugs and they are all CAKED with carbon. So I hit them with some cleaner and a little brass brush. This is not the first time I've cleaned them like this. However, it is the first time they looked this bad. So I put them back in and crank. Nothing. After cranking 3x for 10 seconds at a time I get a HUGE afterfire. I nearly gave my uncle a heart attack and every dog in the neighborhood is barking. Oh my! I crank again and it catches but dies instantly. I try again and the same. Then I crank and use some right foot to keep the car running. It's low 40's out and the wideband is telling me 16-18 and I just say "**** it" and let off the gas. WAY too lean. I get out and shake my head. Now my uncle comes to take his bike out and is yelling at me and reminds me how I really need to get rid of this car
I agree...
So I disable the fuel and injectors thinking my coil **** out on me again. I pull the CAS and spin it by hand and hear the coil ticking. But it doesn't sound like the plugs are ticking. Shouldn't I be hearing the plugs?
I try one more time to start the car. It cranks and cranks and cranks. Catches a little but is giving me that straining whine like it's just a tad bit lean to keep it running. It's right there and just needs a little more gas but it dies.
One more time and KABOOM. A serious ******* KABOOM. I never heard an afterfire this loud before. Dogs start going crazy, and I heard people screaming and sirens. I'm not kidding. I say aloud "OK! That's definitely it for a while!".
I pull the plugs one last time and they are covered in fuel. My conclusion is the plugs are shot. I think they aren't even sparking anymore. I say I filled the exhaust up with fuel and every now and then I'd get enough spark to blow the whole thing. That really was too damn loud...
What do YOU think?
Pre-reading cliff notes: Car went leaned and sounded like a gun. I think the plugs are fubar, need more opinions.
Yesterday morning I took the car out. It started good and ran AWESOME. While it was warming up it was pretty rich. It was low 40's I think and it was idling first low 10's
but it warmed up and leaned out a little. It drove great in the 13's and was idling around 12.5. I went out later to tweak my thermowax & idle screws because the idle wasn't always dropping down when fully warmed up, still staying around 1200. So anyway I start the car and it's stupid rich like before. But this time it warms up, but the idle is weak and it's still absurdly rich! It was also pulling a little less vacuum, 15 rather than 19-20 I have normally warming up. I noticed two things. The thermowax wasn't warming up because the coolant line was pinched, and a vacuum cap had fallen off the back of the manifold. Well the thermowax is one issue which I fixed, and then I put a new vacuum cap on. After fixing both the car was getting harder to start and still running too damn rich. At this point after idling and running around low 10's I figured I must have fouled the plugs pretty bad. It got cold and late, so I called it quits.Now I come out this morning and get to work. I pull the plugs and they are all CAKED with carbon. So I hit them with some cleaner and a little brass brush. This is not the first time I've cleaned them like this. However, it is the first time they looked this bad. So I put them back in and crank. Nothing. After cranking 3x for 10 seconds at a time I get a HUGE afterfire. I nearly gave my uncle a heart attack and every dog in the neighborhood is barking. Oh my! I crank again and it catches but dies instantly. I try again and the same. Then I crank and use some right foot to keep the car running. It's low 40's out and the wideband is telling me 16-18 and I just say "**** it" and let off the gas. WAY too lean. I get out and shake my head. Now my uncle comes to take his bike out and is yelling at me and reminds me how I really need to get rid of this car
I agree...So I disable the fuel and injectors thinking my coil **** out on me again. I pull the CAS and spin it by hand and hear the coil ticking. But it doesn't sound like the plugs are ticking. Shouldn't I be hearing the plugs?
I try one more time to start the car. It cranks and cranks and cranks. Catches a little but is giving me that straining whine like it's just a tad bit lean to keep it running. It's right there and just needs a little more gas but it dies.
One more time and KABOOM. A serious ******* KABOOM. I never heard an afterfire this loud before. Dogs start going crazy, and I heard people screaming and sirens. I'm not kidding. I say aloud "OK! That's definitely it for a while!".I pull the plugs one last time and they are covered in fuel. My conclusion is the plugs are shot. I think they aren't even sparking anymore. I say I filled the exhaust up with fuel and every now and then I'd get enough spark to blow the whole thing. That really was too damn loud...
What do YOU think?
11-28-10, 09:22 PM
#5
My last 1st gen that I ran a big bridge port 13B, RB Holley, full Crane digital HI-6 ignition with race coils, and a 150 shot would burn the ends of my BR9EQ14 plugs. If I let them go too far, the engine would detonate (sounding like a machine gun). Drop fresh plugs in and everything was good again.
Sound like you need to pull the plugs, spin it over to blow all the excess fuel out and let it sit. Drop some fresh plugs in there and try it tomorrow. I've had some really loud kabooms on my bridge ports.
Hope it all works out for you!
Sound like you need to pull the plugs, spin it over to blow all the excess fuel out and let it sit. Drop some fresh plugs in there and try it tomorrow. I've had some really loud kabooms on my bridge ports.
Hope it all works out for you!
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