1990 240/DL Gas Mileage Problem

vincent-1 · Post by **vincent-1** » 28 Jan 2011, 13:29

I have horrible gas mileage, maybe 15-18 MPG, and I've heard I should be getting 25+ MPG out of it. So, what gives? I can try and give you all the info I can. I can follow instructions! Maybe just a tune up???

THE WHOLE STORY
since I bought the car a few weeks ago...
(Note: I have no idea what information is relevant to my topic.)

I bought the car 250 miles away from where I live, before I got it home, I had to bring it to a mechanic because it wouldn't start after I parked it for a few hours (which got me stuck 250 miles away from home for a day.) The next day the mechanic (a Volvo specialist, in Portland, OR) told me it was bad plugs- it wasn't getting any spark. So obviously he replaced them. The car started and I was able to get home. Unfortunately the next day, when I go to start it, it does the same thing it did before, after having a friend look at it (who is mechanically inclined) he said that the plug wires weren't compatible with the plugs that the mechanic put in (the mechanic didn't look? idk)---Anyways, I also own an old beat up (but running) -87 240 So we pulled the old plugs out of that one, and put them in the 1990, since they were compatible with the plug wires already in it--- After that, the car hasn't had any problems starting at all. Though, it does get horrible gas millage, I'm estimating, based on how much I'm spending on gas, that it's getting maybe 15-18 MPG, and from what I've heard, it should be getting 25ish or more. And my gas gage is almost always in the red. I put $20, it goes up to a half tank, but before I know it it's back to red. And It's accurately telling me when I'm out of gas... As I have run completely out of gas once.

(Probably irrelevant information)
Besides the plug, I've also replaced the power steering pump with some help from afore mentioned friend. Steering is fine now. It had bad gas mileage before that though... Also, I've been replacing a lot of trim and other cosmetic pieces, taking them from the 87, to put on the 90

vincent-1 · Post by **vincent-1** » 28 Jan 2011, 13:59

Also, I just wanted to add. I sometimes smell gas fumes outside the car, though, I've checked (as best I could) for leaks. I filled the tank, and peeked under, and nothing is dripping... Sooo...? Thanks for any speedy replies! I rely on this car to get to school

lummert · Post by **lummert** » 28 Jan 2011, 14:13

Maybe a leaking or seeping fuel line? Another thing, do you smell the gas fumes near the gas cap? Is the gas cap making a good seal? Did the new spark plugs have removable screw-on tips?

vincent-1 · Post by **vincent-1** » 28 Jan 2011, 14:54

I'll see what I can find out, I'll have my friend help me check the fuel line. I think the gas cap is good, though I don't know for sure. I'm not sure if the smell is coming from the gas cap, but I'm pretty sure it's coming from the back half of the car, it's not a strong smell, but it's definitely gas fumes... Could a bad gas cap seal cause bad gas mileage? And the spark plugs have a solid tip, the new ones that is, which aren't in the car. The ones that are currently in the car, are from an older 240.

vincent-1 · Post by **vincent-1** » 30 Jan 2011, 22:48

Fuel line turned out fine,and the gas cap has a good seal. I was told it might be clogged injectors too... So, maybe that is it? It does start rough, though after driving around for a while it seems a lot smoother... How could i check the injectors?

Post by **billofdurham** » 31 Jan 2011, 11:48

The only true way to check injectors is on a specialist machine. If you just want to find out if an injector is working try this:

: 240 fuel injectors.jpg (16.74 KiB) Viewed 3845 times

Bill.

vincent-1 · Post by **vincent-1** » 31 Jan 2011, 16:25

I'm pretty sure the injectors are -working- just not efficiently? I'm going to run some injector cleaner through and see if that changes anything. If not, I might try and test with the Ohmmeter... If I know how. Anyways, I'll report back with any info- Thanks!

hawkboy647 · Post by **hawkboy647** » 01 Feb 2011, 18:02

Just throwing this one out, though it doesn't explain the gas smell, you might want to check and replace your oxygen sensor.

jjaV70T · Post by **jjaV70T** » 01 Feb 2011, 20:57

"Just throwing this one out, though it doesn't explain the gas smell, you might want to check and replace your oxygen sensor."
OR disconnect.

.I would check Vacuum,and hose, can the Volvo spec. solve it?? and 250 mi from home was it a deal or scam?..

best of luck GREAT cars they are..