Let's talk about SC400 Ignition Coil Connectors
01-08-15, 08:34 PM
#31
I hope your car is more cooperative than mine was for changing the fuel filter and teeing in a gauge in the engine bay. My factory lines for both were basically welded on at the fittings from whatever %@!$ goop they use. Made for one helluva mess.
The only thing that sucks about changing the IAC Valve on yours is you have to drain the coolant, since the whole assembly has to come off, not just the valve like with the serviceable ones.
The only thing that sucks about changing the IAC Valve on yours is you have to drain the coolant, since the whole assembly has to come off, not just the valve like with the serviceable ones.
It comes off looking like this:
It's one of the higher points on the engine, so it shouldn't be a whole lot, but I get coolant spilling out any of the upper hoses even after draining it.
01-24-15, 11:38 PM
#34
Just to follow up on this thread:
I bought an IACV from eBay and finally got around to get it installed today. While disassembling everything to get the old one off, I noticed that one of my new NGK wires had been pinched pretty badly between the wire tray in front of the IACV and the wire cover, leaving it completely severed and hanging to itself by a tiny amount of rubber. I replaced it with one of the wires I took off a few weeks back and she's running like a top again.
Now, to sell this car...
I bought an IACV from eBay and finally got around to get it installed today. While disassembling everything to get the old one off, I noticed that one of my new NGK wires had been pinched pretty badly between the wire tray in front of the IACV and the wire cover, leaving it completely severed and hanging to itself by a tiny amount of rubber. I replaced it with one of the wires I took off a few weeks back and she's running like a top again.
Now, to sell this car...
01-25-15, 09:24 AM
#36
A severed spark plug wire would certainly be a bad thing, but I'm confused how it could explain the symptoms specific to low-RPM light throttle? Wouldn't the problem remain throughout the entire RPM range?
I don't know if you saw my update to the IACV thread I linked to earlier here, but I'm leaning toward the common issue actually being the connector, not the valve itself. Every time I mess with my IACV, even if I didn't really do anything that seems like it should have had an effect, the symptoms go away. When the brittle plastic clip breaks, I think it allows gravity and engine vibrations to push it down a bit and lose a good connection. So, by any chance did you brush up against the connector when removing spark plug trays and readying stuff for IACV replacement? That may have been all it took, and the severed spark plug wire was totally coincidental.
I don't know if you saw my update to the IACV thread I linked to earlier here, but I'm leaning toward the common issue actually being the connector, not the valve itself. Every time I mess with my IACV, even if I didn't really do anything that seems like it should have had an effect, the symptoms go away. When the brittle plastic clip breaks, I think it allows gravity and engine vibrations to push it down a bit and lose a good connection. So, by any chance did you brush up against the connector when removing spark plug trays and readying stuff for IACV replacement? That may have been all it took, and the severed spark plug wire was totally coincidental.
01-25-15, 06:34 PM
#37
A severed spark plug wire would certainly be a bad thing, but I'm confused how it could explain the symptoms specific to low-RPM light throttle? Wouldn't the problem remain throughout the entire RPM range?
I don't know if you saw my update to the IACV thread I linked to earlier here, but I'm leaning toward the common issue actually being the connector, not the valve itself. Every time I mess with my IACV, even if I didn't really do anything that seems like it should have had an effect, the symptoms go away. When the brittle plastic clip breaks, I think it allows gravity and engine vibrations to push it down a bit and lose a good connection. So, by any chance did you brush up against the connector when removing spark plug trays and readying stuff for IACV replacement? That may have been all it took, and the severed spark plug wire was totally coincidental.
I don't know if you saw my update to the IACV thread I linked to earlier here, but I'm leaning toward the common issue actually being the connector, not the valve itself. Every time I mess with my IACV, even if I didn't really do anything that seems like it should have had an effect, the symptoms go away. When the brittle plastic clip breaks, I think it allows gravity and engine vibrations to push it down a bit and lose a good connection. So, by any chance did you brush up against the connector when removing spark plug trays and readying stuff for IACV replacement? That may have been all it took, and the severed spark plug wire was totally coincidental.
I'm not doing anything more to this car besides listing it for sale. It's mechanically perfect now, with tons of new parts that would cost a new owner tons of time or money to replicate. I've already purchased two new cars so this one's just in the way, sadly. It was my first car and I've babied it for ten years. Hopefully it will go to someone who will continue to do the same, and not trash it like a beater like so many others on this forum.
01-25-15, 08:35 PM
#38
I did not even remove the wire tray before I noticed the severed wire. I'm not sure what you mean by light throttle. Are you referring to the symptoms I had when I was describing my driver's side ignition coil going bad? The only symptom(s) I had was a slightly rough idle and rough acceleration, but there was power.
The engine idles at a constant RPM. There's a very slight vibration at idle. If I add throttle slowly, there's a more pronounced vibration. It seems to clear up in the higher RPM range. If I put the car in drive or reverse and lightly hold the brakes, the vibration is enough to make the car shake a little bit.
Q: What about when you got the engine to higher RPMs? Did it get smoother? Did you still have power while driving?
A: Yeah, it always smoothed out over 35-40 mph, or ~1400 RPM, depending on the amount of throttle. There was never any loss of power evident. Like you, I could usually push through it if I gave it more throttle up front, but even so, I could usually feel a bit of the grumbly hesitation. Then it would be fine for a few days and make me question my sanity.
Exactly what I'm getting. Even if it's not jerking, I can still feel a little bit of 'grumbling'.
Q: What about when you got the engine to higher RPMs? Did it get smoother? Did you still have power while driving?
A: Yeah, it always smoothed out over 35-40 mph, or ~1400 RPM, depending on the amount of throttle. There was never any loss of power evident. Like you, I could usually push through it if I gave it more throttle up front, but even so, I could usually feel a bit of the grumbly hesitation. Then it would be fine for a few days and make me question my sanity.
Exactly what I'm getting. Even if it's not jerking, I can still feel a little bit of 'grumbling'.
At least Ali and I both lost the non-wager.
I'm not doing anything more to this car besides listing it for sale. It's mechanically perfect now, with tons of new parts that would cost a new owner tons of time or money to replicate. I've already purchased two new cars so this one's just in the way, sadly. It was my first car and I've babied it for ten years. Hopefully it will go to someone who will continue to do the same, and not trash it like a beater like so many others on this forum.
01-25-15, 08:45 PM
#39
I was referring to our back and forth on pg 2 of the thread...
I thought we were on the same page, but if not, I apologize. At least Ali and I both lost the non-wager.
I know you mentioned awhile back being frustrated with the direction of newer SC ownership. Sad to see it's gotten that far and you're throwing in the towel.
I thought we were on the same page, but if not, I apologize.
At least Ali and I both lost the non-wager.I know you mentioned awhile back being frustrated with the direction of newer SC ownership. Sad to see it's gotten that far and you're throwing in the towel.
I'm not selling the car because of the owner's group. Though, it definitely isn't a factor that would convince me to keep it. The car is 20 years old, not suited to driving through downtown streets, impractical for what I need now, etc. I sold my vintage 911 a few weeks ago and used that money to buy a 1985 MB 300D turbodiesel, and an E55 AMG. I drive the diesel as a daily (four doors, comfy, reliable, efficient, nearly mint) and the AMG is the new garage queen and fun car. The SC just doesn't fit any of my needs any longer.
Thread
Thread Starter
Forum
Replies
Last Post