Try something for kicks, it sometimes works.
Ever done a seafoam treatment? Do the same thing but with alcohol. Buy a bottle of gas line antifreeze, pull a vacuum line, stick it down in the bottle and let it sip while you rev it up and down.
We used to do that at our shop and it sometimes cleaned off enough carbon from the cat's fins that it worked to get it past the test.
Jay_W
HalfDork
1/12/11 3:31 p.m.
That engine eats plug wires unlike any other, and despises all plugs aside from NGK...
Picked up the OEM NGK plugs. My free retest ends Saturday (if they're even open by then, darned snow keeping everybody out of work), so I'm going back for a second attempt regardless...I'd like to maximize my chances of success!
So, changes that will be made since last time:
New plugs (NGK)
New PCV
Perhaps a bottle of G2P and some Chevron supreme
Optionally, I could also try to get the shop weld in that used cat, just for kicks...if it's not terribly expensive (my guess is it will cost me $50, all told?) it might be better than nothing.
I'm not sure about getting the refund on the G2P if it does fail. On the bottle it says you get your money back "...if all emissions equipment is working properly." Well, who fails when their emissions system is working? That's just silly.
I also like the alcohol idea, but my exhaust sounds pretty rattly, I wouldn't be surprised if I don't have much of a cat left at this point.
Type Q
HalfDork
1/12/11 4:50 p.m.
The other thing is make sure the car is throughly warmed up when they do the testing. I hope it works out for you.
Installed new plugs, and checked timing--my timing cover is on a little bit crooked (woops!), that is, twisted a bit out of the plane of the crank...but from the look of it I had a 13-14 degree advance. I retarded it back to 10 deg.
It does sound like it's misfiring slightly at idle, I think this happened with the old plugs which I had gapped a bit narrower. Using the stock pre-gapped .044 NGKs it may be slightly worse, so I'm thinking this might indicate a weary coil?
I had my local muffler shop put it up on the lift, the whole exhaust system looked like it was in surprisingly good shape...very little rust. I asked about installing a cat and they looked at me like I was a little bit crazy. But, who knows what got in there and fouled it up, I suppose? Hard to tell from looking at the heat shielding.
Test will probably be tomorrow. Stay tuned for results!
Well, as I was checking the timing earlier, the light seemed to be missing more than the engine did. Since it's a wasted spark system this might not be surprising, but I am a bit suspicious of this timing light...has anyone had one go bad and stay off a couple times when it should have blinked on?
I took it in to the inspection station and they read RPM off a similar pickup on the first spark plug wire--the test eventually aborted due to "too many restarts" i.e., trouble reading RPM. The guy at the station thought it was a problem with his machine, so I've got another month to come back and get it sorted out. Although, if it saw the same signal my timing light said it did, that might be an ignition issue.
In the meanwhile I might try to take the cat out and visually inspect it, clean fuel injectors, read resistances on the spark plug coil...you know, all the cheap things I can do.
Jay_W
HalfDork
1/15/11 2:08 p.m.
Set the plugs on the valve cover, unplug the injector harness, and turn it over. How strong are the sparks? That miotter ig coil can go bad, and when it does, you get a tiny lil weak pink spark that won't light anything, when what you want is an arc that'll jump half an inch to the valvecover. This is why my rallycar lost it's stock coil and is now running a Jacobs C4. The miata coil is harder to find in an aftermarket upgrade, but even a working junkyard stocker will get the job done if yours isn't..,