Greetings, my first post on this invaluable site, sorry it's a bit long. I hope someone might offer some suggestions for this odd situation.

My '89 240 has 216K miles and generally runs well. Several months ago I was having hot start problems and traced it to the pump relay which visibly had cracked solder joints. I picked up a few extras at the junk yard for spares, though I noticed they had a somewhat different number. I resoldered them all and and put the repaired original back in. It's given no more trouble till now. I might note that when I was having the previous problem, the main pump would sometimes run a bit loud but I haven't noticed it in a while, I've had to clean the contacts on the power stage a few times, I replaced a failed fuel pressure reg and the filter is probably the original and needs replacement.

Now the new problem is this: I came out of a store and the car wouldn't start. I pulled the fuel line at the pressure reg and cranked it, no gas came out though I could hear the relay click when I turned the key. I put a hose in the tank and listened as I cranked it but there was no sound from the pre pump. I then ran a set of jumpers across the tank pump fuse to the main pump fuse and could then hear the tank pump running. It sparked as I made the connection (key off). The car started and ran fine with the jumpers in place. If I disconnected them the car stalled. I drove home with jumpers in place and the next day I replaced the relay with one of the spares I had. The relay clicked but the car wouldn't start, pre pump again not priming or running. I checked the power stage and it had water in both terminals, I dried them and cleaned the connections, car still wouldn't start. I again used the jumpers at the fuse box and it started. I examined the original relay and saw that one of the traces was blown (like a fuse). I soldered a bridge wire on the relay and reinstalled it leaving the cover off. With the fuse box jumpers removed, again, the relay clicks on but the car still won't start. I put the jumpers back on at the fuse box and it starts. While it was running I disconnected the jumpers and curiously, this time the car remained running. After a few moments I put my fingers on the exposed coil of the relay and it was too hot to keep my fingers on. Though I Assume now there is a short somewhere, I thought the re-repaired relay may still be failing as indicated by the seemingly intermittant function, I again replaced the relay with the same spare used before and this time it started and ran ( with no fuse box jumpers). For the heck of it, I pulled the relay, while the car was running, expecting it to stall, but it kept running!. Since then (two days), the car starts and runs as normal with NO RELAY in it at all. No dash or warning lights come on. If that isn't bizarre enough, I pulled BOTH fuses for the pumps, the car STARTS and STAYS RUNNING without the fuses OR the relay! I fear there is somethings about to burn up and leave me stranded but I'm at a loss as to what is wrong and how the car can even run without the relay or fuses. A few final observations are that when the power stage fuse is pulled it will stall as normal, and the main pump is running and quiet. The spare relays have the #s (004-038-04 / 3523804) on the covers and one has the silver blades, the original relay is #(004-038-01 / 1347764). I'm pretty sure I'm messing with the pump relay and not the overdrive relay (which I couldn't find!). It was located behind the center dashboard under the radio just to the left of the glovebox. Tomorrow I'll pull the fuse panel to see if I can find a short there, I'm hoping for some other suggestions or similar experiences. I'd like to solve this mystery before I get stranded!

Thanks!!

'89 240, and formerly: '86 240 diesel, Two '71 1800e's

And why not register ? If you don't want to use your real e-mail address or anything, just leave them blank or put xxxx in there. It helps us get to "know" a poster by their handle and I personally know at least one knowledgable brickboarder (no, not me) who won't respond to anything by "claiming to be".
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Andy in St. Paul, '91 745 Regina 198K mi, '89 244 141K, '87 245 RIP

You have been playing with the OD relay as the other posters have told you.
OD relay is P/N 3523804.

Fuel pump relay is P/N 3523608 and it clipped to the electronic boxes located in the passenger side kickpanel.

Go take a look at that relay and see if it is not all shorted out, full of water, etc.

Hi Zoom,

Thanks for confirming what Jessie said and coming up with the part # data! I'll have to check the condition of the relay in the car tomorrow. I did grab one of the relays by the ECU from the graveyard when I got the others, and it is part #3523608. I just checked it and it did have a few questionable solder joints so I re-flowed them. I'll switch them tomorrow. That at least solves the question of why the car was running without the relay [overdrive] plugged in. But should the car be able to start and run without the pump fuses? I guess if the relay is stuck closed it would. Now all I have to do is figure out why the OD relay burnt out! I'd love to get that working again.

Thanks guys, I'm going to look around the board to see what I can find out about ECU's and interchangeability for my car, and maybe a little more about the overdrive.

should the car be able to start and run without the pump fuses?

Yes— fuse 4 is for the tank pump, car will run without it. Fuse 6 is NOT USED on U.S. Cars. Pulling it does nothing.

Main FI fuse is the 25 amp blade fuse up near the ignition coil. Make sure all contacts are good there, because the jumper that made it run bypassed that fuse, as well as the relay.

That 25 amp fuse and the Fuel relay are in series. You don't know, at this point, which one might be at fault.

Your jumper just picked up unfused voltage from fuse 6 (6 thru 10 are always hot), and applied it to fuse 4. Voltage at fuse 4 INPUT (Left contact) goes thru the fuse to the tank pump, and from the Left contact to the Main pump as well.

--
Bruce Young
'93 940-NA (current) — 240s (one V8) — 140s — 122s — since '63.

Thanks Bruce,

Looks like all the mysteries are now solved. What was bizarre to me was pretty much routine around here!

Just to update, The relay I was mistakenly messing with was the overdrive relay, as pointed out, which now works by the way. I did resolder it before thinking it was the pump relay, but the trace on the circuit board must have blown shortly after I put it back in. The OD relay coil does click on as soon as the key is turned and it gets hot. I'm guessing it will burn out again soon unless I figure out why.

As it turns out, when I soldered and put back in the OD relay, I also resoldered the terminals on the actual pump relay. I remembered doing that when I popped the cover off today and saw the cheesy solder work I did! Though it was ugly, it did hold up (I think) but I could plainly see another post that I hadn't resoldered before was now cracked all the way around. I put the one in from the junkyard since it had a later date (same part #) and looked in great shape. So far, no troubles today.

Thanks to all for the help, hope something good comes around for you!!

im confused,, if this was posted by someone claiming to be long gone, are we supposed to respond?
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mike, 1988 Volvo 240DL 114k , , previous 79 & 81 Volvo 244s

Hi Mike,

Yep, you can respond, please!, The protocall for this forum is to use the preface, "posted by someone claiming to be...." for anyone who posts a thread or reply who is not a registered member. Anyone can post a thread, even if they're not registered.
I'm a real person, the problem is real and as descibed, I'm just not registered. Been lurking here for years though, this is the first problem I've had that's been tricky enough to get me to post!

I'm Kurt by the way, Nice to meet you (all)!

'89 Volvo 240, '76 BMW 2002. Formerly: '86 240 diesel, Two '71 1800e's, '83 BMW 530e

Doh! Man am I slow! I just realized your joke. No wonder I can't figure out what wrong with the car.

You've been playing with the wrong relay. The fuel pump relay on an 89 is behind the glovebox usually clipped to the ez-k ingnition unit. It is white plastic and has to relay coils in it. One is the system relay the second is the fuel pump relay. It sounds like you are messing with the overdrive relay.
Here are three possible reasons for your nostart:
bad fuel pump relay
failing crank position sensor (causes no ignition which shuts down fuel pump)
failing LH computer (89s computer is known for breaking such that it does not activate the fuel pump relay

Hi Jessie,

Thanks for the suggestions. There is a relay clipped to the ECU, but it's much larger. That was my understanding of where the pump relay was located as well, but after visiting this site, I decide that it didn't look anything like the relays that were being pictured here and related as being pump relays. So I followed the "clicking" sounds when I turned the key and found the relay I mentioned above (white cover, app. 1 1/8"sq. x 2" high, with 5 flat prongs) like the ones picture around this site. After re-soldering this relay, hot start problems that I was having almost daily ceased (perhaps coincidentally?). That was about 10 or 11 months ago. Also, the overdrive worked intermittantly when I got the car (4 years ago) and hasn't worked at all for a few years. If that is the OD relay and that was the problem with it, I guess soldering didn't help! Should the OD relay click on when you first start up (as this relay does)? Am I correct in understanding that the OD relay and pump relay are virtually identical? Anyway, Assuming for a moment that I have the wrong relay, I still can't figure how the car can start and run without either pump fuse in place. Perhaps someone who has access to some books or tech data can identify the relays I have, #(004-038-01 / volvo #3523804) or (004-038-04 / hella? #1347764).

Thanks again!