A few weeks ago I bought a 2003 Buick LeSabre for a remarkably cheap price given its value+condition (supposedly it wasn’t the owner’s car, it was his mother-in-law’s who had passed and he just needed it gone.) I figured there might’ve been some “catch” he didn’t mention, but generally it ran beautifully when I got it, but there are two issues that worry me slightly.
First of all, the gas gauge seems to fluctuate a large amount. Most of the time it’s not major, but the most extreme difference happens whenever I put it into park, the gauge immediately drops significantly. It “jumps” up and down a few times until resting at a much lower level, usually almost half the capacity lower than it was before. When I start driving the gauge raises again, and it gets at its highest after going on the freeway. It drops a little bit when I’m at a stop light, but it’s never as immediate or as much as when I put it into park. I wouldn’t be too bothered by this except for the fact that I can’t tell which level is more accurate. I can’t tell if the tank is halfway full when it says halfway when driving, but nearly empty when parked, and since I drive delivery for several hours a day I absolutely don’t want to end up out of gas because I thought there was more. I’ve been going off the parked reading just to be safe, but it would be nice to know if it is the driving reading so I can have some peace of mind—especially if I want to go on a road trip or visit another city with it where I’ll be on the highway continuously for several hours.
The second issue wasn’t there when I bought the car, it only started happening about a week ago. When I try to put in gas, the pump immediately clicks off due to resistance as if ti was full, even though it absolutely isn’t full (this can’t just be a gauge accuracy thing, it doesn’t leak and it happened even after refuelling haven driven 33 miles the night before). The only way I could fill up the tank is to barely pull the trigger down at all and let it drip in extremely slowly. Yesterday when I filled up, I had the same problem but I was able to use muscle to really shove the pump into the tank and from there it let me pull the trigger down all the way just fine, but I haven’t tried filling up since then so I don’t know if that was a one-time solution. Another poster on here had the same problem with their LeSabre and said it was likely a clogged EVAP system—assuming the problem didn’t go away after yesterday, is that dangerous to drive? If I have to continue forcing the pump in or slowly, is that going to be bad for the car?
Could these problems be related? How difficult/expensive would they be to fix? Would appreciate any advice, I only got my license this year and I’ve learned a bit about cars in that time but I couldn’t be farther from an expert.
Cheapest fix on worrying about fuel level is to fill the tank, set your trip meter to zero and then fill it back up at xx miles. Do the math to figure out how many miles you will get out of a tank full of gas, then make sure you fill it up 50 miles or better ahead of that. Example: car has 20 gallon tank and gets 20 miles per gallon, you know a tank full will get you approx 400 miles, so set the trip to zero, and when you see it around the 300 miles mark, fill it up again and remember to reset your trip to zero when you fill up.
As far as pumping gas in, cheapest fix on that is hold the pump handle upside down when filling the tank. So instead of the pump lever toward the ground, it will be pointed toward the sky. You will look a little funny pumping gas, but that should work for you. I am serious, this isn’t a joke, learned this trick many years ago from a gas station attendant when I had a vehicle with the same issue.
Yes, the “slow fill” symptom is probably an EVAP problem. Unfortunately, it’s fairly complex and can get complicated to troubleshoot. The ‘canister vent valve’ may be clogged or defective, which shouldn’t be too expensive to replace.
I’m going to take a guess that the gas gauge problem is voltage-related. The voltage regulator on the alternator may be shot; I’m thinking the voltage is going up with the RPMs of the engine and the gauge reads higher with the increased voltage. I’m not sure if you would notice other things (lights, blower motor) changing as well, though. There also may be a voltage regulator for the dash gauges, but I’m not sure why it would fluctuate with engine speed in that case.
You’ll need a real mechanic, not some kid at a chain shop, to diagnose the problems (I doubt they are related, but it’s not impossible). As far as car repairs go, these might not be too pricey-hundreds, not thousands, of dollars.
Fill the tank up, and set the tripmeter if you have one, or make a note of the odometer reading. drive for, say, 100 miles, fill the tank up, and note how many miles and how much fuel it took. You can figure out how far a tank will last you, and fill up when you get below 1/4 tank or whatever. Reset the tripmeter each time you fill up. If you note the gauge reading before you fill, you should be able to see if it’s consistent, and what it actually indicates.