Just bought a '90 Metro XFi, have questions...

[ohmycivic]

Yeah, the silicone was a quick fix, I replaced the line today and it's all good.

About timing adjustments: do I rotate the distributor counter-or-clockwise to advance it? Can I make adjustments when the car is running? How do I know where the "stock" setting is? I ask because I'm having a problem with the car still running for a second or two after I kill the ignition (changing the plugs helped a bit). Any ideas what else could be causing it?

I had to lie to the car. The manifold bolts are frozen, as are the bolts for the exhaust header where it's cracked. This was messing with the o2 sensor, which is also frozen (making the mixture way too rich). Yeah, fun times. I'm trying to find a manifold, so in the meantime I bought a new sensor and plugged it in, but I sealed it with tape and secured it in the engine bay. Before everyone jumps on the "that's a terrible thing" bandwagon, know that it's only a temporary fix until I find a new manifold and flanges for the header.

I checked my control arm mounting area based on JM's guide. It looked slightly rusty, but a few minutes of sanding showed it to be just fraction of a millimeter of surface rust. I sanded it all down to the metal then hit it with some rust stop primer. Repeated the process for the control arms and a few other areas, then I ran out of the stuff. I'm going to pick up a few more cans and basically coat the underside of the car in it piece by piece.

I talked to the previous owner (and got in contact with the other two previous owners as well, I'm only the 4th) and found out that the car had actually been stored -- covered outdoors -- for 10 years, which explains why there's virtually no "critical" rust but the areas around the lower edges of the doors are so rough.

I also still need the wire color identifiers for the stereo install, so if anyone has those that'd be great.

[ohmycivic]

Okay, I'm planning on using the Coyote X method of interior improvement -- carpeting over the frame -- but I have a question or two.

After removing the interior plastics I have a bunch of space in there between the frame and the "skin" of the car. I'll certainly take the asphalt off, but I'd still like to dampen the road noise. Can I jam a bunch of polyethylene or polyurethane foam in there? There's a company which produces the stuff locally (in fact, they have recycled PE foam... go green kids) so availability isn't an issue, and unless I REALLY cram it in there the asphalt I'll be removing will still weigh more, meaning I'll have a net weight loss.

Does anyone know the +'s and -'s of PE and PU? I've found quite a bit of information online but I'd prefer it from someone who's worked with the stuff before. I'm assuming that low density will be the way to go (less weight) but again I have no experience with the stuff. Ideally I want something that's not going to rot and doesn't trap water since I have a rust issue (for now). Also something that's not going to burst into flames should I encounter a day or two over 100 degrees... yay global warming!

[ohmycivic]

So the JB Weld didn't hold... it's only rated to 600 degrees apparently, so it burned right off the manifold. I picked up some stuff at Auto Zone rated to 2400 degrees (Thermo Paste I think) and applied it... just need 3-4 hours for it to dry then a hit from the heat gun to cure it.

The O2 sensor cheat I employed didn't work. It seems that the sensor doesn't start working until it hits 600 degrees, which is why I needed to cheat the manifold instead. I'll eventually replace it (and probably most of the exhaust) properly, but before winter I just want to get it running.

I managed to figure out the wiring for the radio, too. Mostly trial-and-error and a bit of common sense.

My fuel leak also reappeared in roughly the same spot(s) where the line hooks up. There must be some teeny-tiny holes in the metal. Going to work on fixing that after I get the thermo paste cured.

I've been reading up on hydrogen generators. A few years ago I wrote them off as tomfoolery, and was all kinds of proud when independent tests agreed that they actually reduce FE. Now I've been reading that the trick to making them work (and what the independent tests WEREN'T doing) is getting an inhibitor of some type on your o2 sensor (most people seem to use modified spark plug defoulers) since the added hydrogen tends to throw off the readings and the the mix gets richened. Before I take the time to build one I was wondering if anyone who isn't trying to sell me something and has real-world experience with the hydrogen injection (plus o2 sensor modification) could chime in.

Also, yes I am aware of hydrogen embrittlement, but I know very little about it aside from what Wikipedia has to offer. Any additional information would be great.

[ohmycivic]

Okay, so I get the feeling the fuel/air mixture is running rich since I'm only getting about 30-40 mpg. The Thermo Paste is holding, so it's not an air leak into the manifold anymore. I even did a neat little trick to restrict airflow to the o2 sensor using spark plug defoulers. This seems to have helped a little bit in around-town testing, but I've yet to go on any substantial trips to really get a solid indication of how much. I'm still getting an amazing amount of sputter when I accelerate, and the engine still runs for a second or two after the ignition is turned off.

Sadly, I'm out of things to try since I'm not getting any ODB codes (then again, I wasn't in the first place so it probably never was the 02 sensor). Not really knowing what would cause this beyond a bum 02 sensor I once again throw myself unpon the helpful mercies of this forum. I've got a 1000 mile weekend coming up at 10AM tomorrow, and if I can't work out the kinks I'd really like to at least have some things to try during my stops -- so shotgun me with a bunch of ideas on things to adjust/check since I'll only have sparse internet connectivity. I'll be taking a mostly-full set of metric wrenches and sockets with me.

I'll be going over vacuum lines after I finish typing this, though I'm pretty sure a broken line would produce an error code. I'm also going to toss in a new air filter even though the one that's in there is a K&N... never know, it might not be restricting airflow enough...

I'll report back with results, in the meantime thanks in advance for all your help!

[Coyote X]

On the old OBD1 cars before '95 it is pretty hard to get the check engine light to actually come on unless a sensor is totally dead or unplugged. If it is just not working properly the car probably won't give you a check engine code to look at.

The sputtering can be a few things but the easiest thing would be to get a new distributor cap, rotor, plugs, and plug wires. I just did all that on my car and it was about 50 bucks for everything. The distributor caps don't hold up long but since you don't know when they were changed last it would be best to just do them all so you know they are good. If the car is missing that will make it run rich because the oxygen sensor sees more oxygen and increases the fuel.

That should most likely get it running a lot better. Just make sure you keep track of where the wires are when you are swapping distributor caps so you don't get the wires put in the wrong places. If you want to smooth it out a bit more you can turn the distributor a tiny amount clockwise to advance the timing. Just turn it a very small amount like 1/16 of an inch. Just listen for knock while driving and back it down if you hear any.

If you think you have a vacuum leak the fastest way to find it I have found is get the car warm and idling. Use starting fluid and start spraying the hoses one at a time. If there is a leak the idle will pick up when you find it. Then you can look at the hose closer and figure out what is wrong and fix it.

[ohmycivic]

Thanks for the advice, Coyote X.

On the plugs/distributor/wires: This was my first thought, and I replaced it all last week. It got rid of a now-and-then miss, but the sputtering/chugging is still there.

On the vacuum hoses: Some of 'em looked shaky, so I replaced pretty much every hose that was in there and made sure they were all sealed up tight. No change, but there does look to be a "lead" where a hose should go that has nothing attached to it. Mr. Haynes has been trying to help me figure out wtf it's for, but he seems to have no idea. It's back behind the airbox closer to the passenger side of the car, pretty low in the engine compartment. It's not coming out of the engine, but rather the (firewall?) Haynes doesn't seem to have any pictures of it, and I'll try to snap one when it gets light out (40 degrees dark and rainy @ 5:30am right now)

[ohmycivic]

I found another naked hose lead (on the airbox -- damn near impossible to see, happened to accidentally feel it) and connected it and the previously mentioned naked lead with a hose. No change in how the car runs.

If I can't get it figured out by Wednesday it's off to the shop for a general tune-up. Hopefully they'll be able to at least find the problem.

[ohmycivic]

So over my five-days-away-from-home I essentially took apart and cleaned everything attached to the engine. Removed a lot of gunk from the parts under the air filter, cleaned my electrical connections, disconnected and cleaned hoses and the nozzles they attach to, etc. Essentially, everything that 8-12 sized wrenches and a couple screwdrivers could do.

While I can't nail down exactly was causing the problems, it's no longer a problem. I'm up to the high 50mpg range in town, which kinda surprised me considering that's above EPA estimates and this car is lacking in the aerodynamics department (plenty of rusted-through spots not visible in the pictures I took, pretty much the horizontal stuff around the bottom edge of the body).

I also have amazingly low acceleration over 55mph (which is perfectly fine with me), quite below what even a Geo should have. Putting two and two together, I figure that my o2 sensor spacer is doing a fine job of leaning my fuel mixture. It trips the check engine light for a few seconds every now and then, and I'm unable to correlate it with any particular aspect of driving, so I'm assuming that it's usually just barely getting enough oxygen to maintain the bottom edge of the requirement before a low voltage signal is sent.

For those interested, I used a 15/32 size drill bit to bore out the spark plug defouler. I did a piss-poor job of it since I didn't have immediate access to a drill press, but the sensor just fits (tight against one side of the hole, thermal expansion had me worried). Two defoulers came in the pack, so I might secure the use of a press to bore the next one out at the same size or go up to 1/2.

On a side note, my fuel filter is a pile of rust with hoses coming out of it, and the bracket isn't much better... I tried to fit a wrench around the bolts and they just kind of crumbled. Anyone have any bright ideas? I was considering a relocation...

[ohmycivic]

Took my car to a repair shop today to get an estimate on my rear brakes which have been squealing for a while now... essentially everything has to be replaced as my parking brake was locked up. Looking at over $300. I'll probably just pick up the drums, springs, and pads myself for less than $100 and do it myself.

While they were at it I had them look at the fuel filter/bracket. They said that salvaging it is pretty much hopeless. Can't even use the old bolt holes. So, does anyone know whereabout I should relocate my new fuel to and how I should secure it?

[Coyote X]

What I did was just rip the old bracket and stuff off mine with pliers then use large hose clamps to clamp the filter onto a piece of metal. I just ran a self tapping screw through a solid looking piece to hold it solid. Zip ties would probably work just as good and be easier to remove next time you change the filter. Just be really careful with the gas lines and try not to bend them much. They are probably really rusted and would be easy to break if you get carried away bending them around.