Hello everyone! I've recently taken ownership of a '93 240 and enjoy it. However, I've noticed that it can be hesitant to start at times and have determined that the in-tank fuel pump is not working (wires corroded and snapped off at sending unit).

Car still runs and starts fine, albeit with slight hesitation now and then. Been driving it for a few days - I got a new sending unit assembly and pump.

I have a 700 mile trip and might not have time to put this in.. Aside from the risk of it not starting (will take extra gas) how much should I worry about that main pump wearing out?

I know this is a hard question to answer, looking for insight.
Thanks.

 

Do you like to tempt fate on such a long trip ? If the main pump burns out ( from cavitation ) on your trip,you'll have to replace both pumps alongside the road or tow it home. Imagine drinking through a straw that is partially pinched shut. That is what the main pump is doing when it draws fuel all the way from the tank through a dead pump. Volvo put two pumps in the system for a reason. I would spend the money and time to replace the in tank pump before venturing very far.

 

about a year ago my in-tank pump died. I drove without it for about less than a week(let say 150 miles).
2 months ago my car wouldn't start because my main pump died(it was original one from 1988) and i had to replace it.

So i don't know how well is that related, but there you go my experience.

Just remember that main pump is fairly easy to install but it cost little bit less than $200.

 

Thanks for your insight! I've dropped it off at a mechanic hoping he'll get it done quicker than I can. The rust is bad, couldn't get the sending unit out.

And yes I know if it breaks on the trip it would be bad. But being late to my event would be costly (paid for Team O'neil Rally school).

 

Did you purchase an OEM sending unit or the aftermarket unit? Be cautioned that the aftermarket sending units have a reputation for having the wiring incorrect. This needs to be checked prior to installation or it will have to come out again.

When I replaced mine, they had the fuel gauge and the transfer pump wires reversed in black connector. I have also heard of cases where the two wires running to the pump were reversed causing the transfer pump to run backwards. May want to warn your mechanic as he may not normally check these prior to installation.

 

I'll warn him. But he won't be able to get the sending unit lock ring, a part I forgot to get, in time. So it looks like I'll be driving it. If it breaks I'll get a rental car...

 

Don't worry about the lock ring, you can reuse the old one if you're careful not to destroy it removing it. I replaced my send unit/in-tank pump recently and could not get the replacement lock-ring to stay in place, so I ended up using the old ring anyways! If it gets bent removing, it's pretty easy to bend it back into shape.

 

I couldn't even *see* the lock ring because of the rust.
Anyways I made it 700 miles to my destination.

 

I didn't read this whole thread again, but if your' tank pump is out, don't let the fuel level get much below 1/2 tank and the main pump will probably be fine.

 

So I drove the car about 2k miles so far, and kept the gas tank above 5 gallons except for one occasion where it had less than a gallon left... I plan to sell it in a few days to a friend who wants it dearly (I only paid $500 for it, so passing it on).

Now. Issues... Sometimes the car will hesitate and stall every time I give it gas. Consistently. Then I let it sit for a half hour and called AAA. Then the car started and drove home just fine.

Will the car start without the main fuel pump? I'm thinking the relay is bad due to increased current draw, or maybe I've damaged that pump now too.

 

Car will not run without the main pump. Could be the relay but it may be that your main pump has had it. To test the main pump use the instructions on this site:

In the Tank - 240 Volvo Tank Pump and Sender

If it doesn't run when you jumper the fuse then your main pump is failing. If it runs then it may be the relay. It's not a definitive test though since the main pump may fail intermittently at this point. Relays tend to fail the same way. The best way to check is to wait until it won't start - then perform the diagnosis. If you don't hear the pump run for a second when you turn the key to the II position but it runs when you jumper the fuse then it is your relay.

 

the car won't run at all without the main pump.

with the tank pump broken, it will run very poorly, if at all, with less than 1/3rd tank of gas.

 

Actually seems like the AMM sensor, haha. Love this car.

 

I checked the codes and the plug to the AMM sensor was loose. Runs better now.

Oh, and the oil light seems to come on under hard acceleration from a stop and sometimes on warm stars. It had a recent oil change. This poor car, man...

 

oil light coming on in those conditions may mean a weak oil pump, or a tired oil pressure sender... or you're rather low on oil.

 

It had hardly any oil left...

 

Where did it go? If you are losing that much oil between changes then you must have a fairly large leak. This happened to my car once and I found my engine mount had collapsed onto the oil filter which sprung a leak. Oil was everywhere - very noticeable.

 

Yeah the mounts are bad so I'll take a look.
It might burn oil. It had about a quart left, and I put about 2k miles on it since i bought it this month, and was changed in June.

 

It ate the oil, in about half a year (4k ish miles, I'm guessing).

Gave it a seafoam treatment and sold to a friend who will do a v8 swap after fixing the rust and restoring it.

Thanks for all your help guys. Now I want to buy an old Volvo now that I'm back in California.