Fuel economy?

The sidewall writing on the tires calls for 51psi, so that's what I go with. I figure I load it down daily with hundreds of pounds of mail and packages and then go curb hopping.

As for wear on the engine, yeah, it's the original engine. But the change in fuel economy shouldn't have happened over just a few months and 10k miles. Plus the oil stays pretty clean up until about 5k miles. With all of the idling hours I put on it, that's solid. And it loses very little oil. Maybe a quart between changes, and those changes aren't exactly on time. Also, while it's no powerhouse, I believe it has retained every one of it's miniature horses over the years. It runs quite well, even with the throttle wide open. Yes, I open it up occasionally on all of my route cars to try and keep the carbon buildup from getting so bad.

I have noticed 2 things over the last couple of days though. 1, it seems the idle is high when cold. About 1500. If I drop it in gear and just let of t of the brake, it'll pull itself up to 15mph and even shift to second gear. Maybe I need to look at the IAC motor and bore, and possibly clean the throttle body itself. Would you have any other suggestions on that end?

I also think 1 or both of my front brake calipers may be sticking just a bit. This happens on mail cars all the time. I say that because after just driving around a bit (normal errand running) I felt the front wheels and they were very warm. Warmer than they should've been, I think. I'll grease the caliper pistons and see what happens.

What do you think? Would you have any other suggestions? I hate wasting time pulling things apart and cleaning/fighting with them if there's no chance it'll work.

Just confirmed the front passenger caliper is sticking. After a 20 mile drive down I40, it's considerably warmer than the driver's side. Short term fuel trim stays between -2 and 1, mostly right on 0. I still want to look at that idle though. I know it should idle a bit higher when cold, but not 1500. I'm thinking 1000ish on most 4-cylinder cars.

I greased the passenger side caliper piston using PB Blaster and now it stays cooler than the driver's side. So I guess that means I've got to do the driver's side too. An old trucker taught need to pull calipers off, pull the rubber boot that goes around the piston, and stick the straw of the aerosol penetrating oil in there and spray until you can't get any more in there. That'll clean off the built up brake dust and the renew the caliper. Also do the same with slide pins. I've been doing this for years on my route cars. Works well. Especially in the front passenger wheel that takes all of the pressure all day long.

Never thought of that. Honestly though, the PB blaster seems to have worked. I took a short vacation on a budget. Since it's my most fuel-efficient car, even with the increased consumption, I drove it. 265 miles, mostly highway, the last 50 ranged from basically nonstop 25 MPH to 45 MPH. It used about 9 gallons. Not terrible, but still not what I'm looking for in the easy driving miles.

So, I scanned it when I got there, before turning it off, and just got the same old P0420 code, set and pending again. Nothing else. Live data showed nothing unusual except short term fuel trims around -7 and stable there. That's a rich condition, correct? But not enough to set a code. As I recall, most cars need about 9+ (-/+) to set rich/lean codes.

Fuel tank was near E, but no gas light. I know from when I bought the car there's at least a few gallons left when the light comes on. It was so low I thought the gauge was broken when I bought it. Didn't even move when I put a gallon in from my container. Anyways, whenever I got out and opened the gas cap, I got a pretty good whoosh sound. Not sure if it was sucking in or pushing out. Again, no EVAP codes. New gas cap as the old was leaking awhile back.

Left it idling for a bit and fuel trim held. This is new. Could that be caused by the "extremely high flow" converter and 420 code? Would a proper non-fouler fix it? And is there anything else that could cause this?

The air filter is clean and fairly new. MAF is new. The plugs are new and OE.

Sorry to fire off so many questions and be so long winded. It's how my brain works. Kind of going through a diagnostic process while typing and being thorough.

Hehe, okay, I'll just come out and say it. There is no converter. Straight pipe. Hence the "extremely high flow." Frankly, cars run so much better without them.

No, the fuel trim did change the one or two times I nudged the gas but returned to the -7ish number.

Sorry, I haven't got back to you earlier. I haven't been driving it lately, as it's the holidays and I've had to get out the big guns (99 Century) to fit the packages. I'll drive it one of these days and let you know.

The vehicle seems to have developed a tiny coolant leak. Can't find it atm (guessing might be heater core starting to go) so I used the micro mail machine for a day (this thing). I did notice changes in both upstream and downstream sensors. But downstream seemed to be a laggy. That could be the scan tool. Or it could be the sensor getting old and dirty (230k). I'm thinking I'll swap it. See what it does. If better, keep it and put on the non-fouler. No better, return and still stick that non fouler in. At least maybe I can get rid of that annoying p0420 code.

Okay, so it's been a while. Working for the post office through the holiday doesn't afford much time to fix the cars, even though that's when I use them the most sadly. Anyways, I got to tinkering with this issue this morning while waiting for my sister to come out of work, and I saw this. Haven't seen one since the early 90's and didn't think anyone used them anymore. It's an idle adjuster. I tried adjusting it but to no avail. The throttle wasn't touching it anyways, even with the cables loosened and me pushing it all the way back. Just thought I'd share.

I figured if it's holding the throttle open slightly, then it would bump the idle just a bit. The previous owner was a machine maintenance man at the post office and fancied himself a mechanic. You should see the horrors I've found, like the air filter that hasn't been changed in the 100+k miles he'd driven the car. I asked him when he changed it last. His response was. "What air filter?" Loose battery terminals? Stick a screw in there. Oh, any old fuse will work! As long as it has at least the right number of amps on it. I don't need to replace that cracked turn signal socket. A zip tie will work just fine. The signal will even work. Occasionally. Well, never, really.

You get the idea. Again, $300. You expect these things though.

That air filter was so dirty the MAF's filament was caked with crap. Unplugging it and running the car sans filter was better to get it home.

Anyways I'm about to drive the car with a passenger (lucky her gets to ride in my luxurious route econobox car) and will have them take video of the sensors live data. Will upload it later on today hopefully. Sorry I get so long winded. I like writing these things out in detail, so I don't miss anything and end up bloviating a bit.

Okay. I finally got around to messing with it again. Now it is showing a P0171 system too lean B1S1 code. Can't find any obvious vacuum leaks so I'll have to get out the spray bottle later and tinker. But I got the video. I took two because I was shooting them myself and unsure what the quality looked like as I went. Neither is terribly good. If you want, I can retry in a few days.

The files are rather large. If need be, I can upload them to YouTube and put links here to save the storage space on your servers.