So, here's what happened, as far as I can tell (it's long, but every detail might be necessary for some genius out there to diagnose my problem):

I was only able to change five out of six sparkplugs because the boot on the one I couldn't get out came off the wire and remained on the sparkplug, preventing me from being able to get the sparkplug socket in there to get the old one out (any suggestions on this problem would be much appreciated, by the way). The other five came out nicely, and I replaced them just fine; I've done it before without incident. The next thing I did was change the oil; no problems there. Then I put brake fluid into the transmission fluid receptacle which was running low; my mechanically inclined brother told me that stuff is interchangeable with transmission fluid, so I trusted him and let him pour it in. Then I put Seafoam into my gas tank, and thought I was ready for my long trip to North Carolina from DC.

I was wrong.

I noticed after four hours of freeway driving, once I got onto the surface streets and started driving at lower RPMs, that there was a slight "chug" whenever I would lightly accelerate while going between 20 and 40 miles per hour. It happens between 1200 and 1900 RPMs, and then acceleration is smooth. It has the same feeling as running out of gas -- a few chugs, like its about to die, and then it perks up again and is fine from 2000 RPMs onward. If I keep my foot steady on the pedal, I can pretty much keep it chugging as long as I want; when I press hard and speed up, it goes away. Also, when stopped, it will do a single chug at irregular intervals, but I'd say about every 40 seconds to a minute, or so.

Any ideas? Is my car about to blow up?

Thanks,

jimmy

 

You put brake fluid in the trans? Is it an auto or 5MT? If auto, only thing I believe it'll do is make your seals swell up, old trick for quickly (and temporarily) curing a leak. If a 5MT, then you went through a fair amount of trouble, unless you just mean you put brake fluid in the clutch master cylinder, which is okay.

Hell, it could be missing from that old plug that's still in there, or since you broke the coil, a bad connection.

 

It's an automatic. If it's a misfire, then wouldn't the symptoms be a little more regular and frequent? I mean, why only in the low RPMs? And why are the chugs random when stopped? Either way, I do have to get that last sparkplug out and replaced. Problem is, it's one of the three in back (the middle one in back, to be precise) ... so does that mean I have to take the engine apart to get to it?

 

I'd start by replacing the coil pack and swapping in the last plug

 

Thanks to you both for your responses. I'm going to buy a pair of extended needle-nose pliers to see if I can reach the stuck boot.

Much appreciated.

jimmy