Nope a 240 will start with no in tank pump...to test in tank pump you can remove back line from fuel pump and then have someone turn it over if gas flows out it is working. When testing pressure you are testing the high output main inline pump. A bad in tank pump usually will cause rough idle or dying going up hill(sometimes) but would not cause it not to start...a bad main pump however would.

 

It's getting late here in Ohio, so I will be back at it maybe tomorrow, or it could be a few days.

My next plan is to get to the ECU- thanks to the person who pin-pointed its located- and see what is going on there.

If that does not get me anywhere, next I will be looking into the crank sensor that tony1963 mentioned. He said it was above the bell housing. What's the bell housing? Anyone want to enlighten me about anything they may know about the crank sensor?

Thanks again, and please stay tuned. Like I said, it may be as much as a few days before I update this thread, as school is still going until Monday, then I'll have 2 weeks to devote to working on the car.

 

You have no crank sensor on an 84..89-92 240's only. Your pick up is a hall sensor on the distributor but if you have spark that's fine...you spray starter fluid car starts...fuel problem not spark.

Here's another test you can do. Also, if you ran car completely out of gas and in tank pump is bad you will have a hard time starting...get more gas in that car..at least a quarter tank or more... For 75-84 place a jumper wire on the left side of fuses 5 and 7. For 85-93 place a jumper wire on the left side of fuses 4 and 6. Both the in-tank and main pumps will now run constantly, listen for them. If the car starts with the jumper installed then most likely the fuel pump relay is bad. For 85-93 the system and fuel pump relays are combined into one package, clipped on the firewall above the passenger's feet. As a safety feature the pumps won't run unless spark is present.

 

was the light blinking when you cranked ? thats the important part. they are all wired together, so any one is all you need to test.



re: pre-pump, even before that, if you're going to shotgun parts, I'd look at the fuel pressure regulator, easier to replace and cheaper. but I really really hate repair-by-shotgun.

 

I am going out to the car now to attempt a bit more troubleshooting. I need to know, though, what is a jumper wire so I can do the fuel pump test with the fuses? Where do I get this jumper wire?

Also, Pierce, the fuel pressure regulator is it that silver device with a hose coming out of it and running into the intake?

I'm also going to put at least ten dollars in the tank as well.

Going to check the ECU as well.
Hopefully I see some results soon. . .

Anyone feel free to contribute...

Also: No main ground or anything else is unhooked, I have triple-checked all the obvious.

 

Just removed the Jetronic Green-labeled ECU. How do I know if it is good or bad?

I overlooked everything in one thing caught my eye, but I'm not sure if it means anything or not.

The silver "teeth" - if that is what they are called- inside the female harness that connects to the ECU, it appears that 2 of them are missing. There are two columns of "teeth". I'll call the right side of teeth the side that is on the right if I were going to plug it into the ECU. This side has 12 teeth and the other has 13.

Well, the second and seventh tooth from the bottom are missing on this right side. I'm not sure if that is how they are made, or if that could even cause the car not to start.

I've attached a picture of what I mean.

 

the Fuel Pressure Regulator is bolted to the fore end of the fuel rail, and has the return line back to the fuel bank coming off the aft end of it, as well as a thin vacuum line back to the intake manifold. thats part #5 on this diagram...


(click for full size)

fuel comes from the fuel pump via the hose at the top-right, goes through the fuel pipe #1, down to the FPR #5, then returns to the tank via the hose 16. #15 is the vacuum line. if you had access to a fuel pressure gauge it would be attached between the intake hose (top-right) and the fuel pipe #1 (this requires volvo-specific fittings on the gauge).

A few other parts of possible interest on that drawing: #30 is the idle air control valve. #52 is the fuel injection ECU.

 

pretty sure thats normal. the best way to test one of those is to plug in another one thats known good. as someone else said, those early LH2.0 'green' ECU's are notorious for failing.

 

Anyone know about how much them special adapters cost to test for fuel pressure? Just a thought....


Also, with the ECU taken off I do not know which direction to go from here. Really, really did not see this coming.

I'm about out of things to test at this juncture, and about the only thing I can say is it's probably a fuel problem.

I think I'll take a shot in the dark and spend the $65 for a new fuel pressure regulator and $60 for a known working used ECU.

If this does not work I can always send the regulator back and just be out $60 for the ECU. At that point I may consider scrapping her for a few hundred bucks.

Alas, one last piece to add:

Like many of these volvos, the plastic insulation that covers the wires running to the small grey box toward the right side of the firewall behind the engine has gone bad on all wires. There is about I don't know, 6 or so wires that are now bare. I know it's not the right way to go about it, but I covered each one with black electrical tape as a temporary solution.

However, I do not think this is why she is not starting due to the following reasons:

The car ran excellent the last time it was drove and parked. The wires never touched each other to short anything. Also, I taped them and the car still starts with starting fluid.

 

Update:

Out of frustration and desperation, mixed with a dash of ignorance and blindnedness, I disconnected the fuel rail where it goes down and connects at the Fuel Pressure Regulator. Whether right or wrong, my rationale was to see if fuel was for sure getting to the rail at the injectors. It is. As soon as I loosened the hex nut fuel poured out.

Now I am confused. Does this tell me anything I didn't know before or get me any closer to identifying the problem?

If fuel is getting to and past the injectors, and down to the FPR, how could the car possibly not start, given that adequate spark is present.

Also- If fuel is getting to the FPR, why does it not come out of the FPR when I disconnect the vaccuum line?

Experts, please, please enlighten me...

O, also, is EGR Valve the same thing as Fuel Pressure Regulator? The guy at the Auto Parts store said the FPR was the "EGR" valve when I showed him a picture of it because I did not know what it was called.

 

no. the EGR is completely different, if your car even has one, in 84, I don't think so.

you said you had a test light on your fuel injectors, but it wasn't clear to me if you said it was blinking when the car was cranked over. that blinking part is really important.

fuel should NEVER come out the vacuum port of the FPR, if it does, that means the diaphram inside is destroyed. fuel goes in from the fuel pipe and exits via the return line to the tank that comes out the aft side of the FPR. the vacuum line modulates the pressure on the fuel rail so when the throttle is closed and you have a high vacuum (aka low manifold pressure), the fuel pressure is lower too... when the throttle is wide open (0 vacuum), the fuel pressure increases. it should always be about 43-44PSI above the manifold pressure, or 43-44psi total if the vacuum line is disconnected or the engine isn't actually running. of course, you only have fuel pressure when the main fuel pump is running (it typically runs for a second when you turn on the key, then runs when the engine turns over as detected from the crank angle sensor thats off the engine flywheel)

 

I didn't mean the vaccuum side of the FPR, sorry. I mean, I have my terminology incorrect, that's all. Looking at the diagram on the 3rd page, I understand fuel comes in from the line marked #1, then comes down and out the AFT side of the FPR. It then head up the hose marked #16. If that is in fact correct then all I am trying to say is, shouldn't I see fuel coming out of the AFT side when I disconnect hose marked #16?

The only reason I ask is because I disconnected it and I didn't see any fuel come out which I thought it was suppossed to go back up hose 16. Am I wrong?

New Fuel Pressure Regulator ordered from Oreilly's is coming from Michigan and should be in by 1030 am. Any suggestions for putting the new one on? Do I have to do anything special once I put it on?

 

I probably would have ordered that from TascaParts.com who sells real volvo parts at a 20-30% discount... but thats neither here nor there...

ummmm, according to the 7xx/9xx FAQ on volvo EFI systems thats on several sites (ok, those are newer cars than yours, they use LH2.2 or LH2.4 instead of LH2.0 like your 84, but the basics are the same on all the LH systems), you should see about 0.5 to 1.0 gallon/minute, or about 1/2 ounce per second, coming out of the back of the fuel pressure regulator when the fuel pump is running. Are you SURE the pump was running when you disconnected the line? it doesn't run but a second when you first turn on the car, you have to crank the car over or it has to be running, or you have to jumper the fuel pump per the instructions someone above gave.

of course, exert extreme cautions when playing around with gasoline and electricity, a little spark while gas is splashing around can burn the whole car down. and more.

 

Yes- fuel pump was definitely running I felt it run I heard it run- that's what everyone told me to check for as a preliminary way to see if its running.

I just plan to take the old FPR off, pick the new one up at 1030, then put it in place of the old one, put lines back on, and crank it see what happens... any objections ? ?

 

I think before I even did that, I'd disconnect the other fuel line that goes to the skinny noodle on the aft end of fuel pipe #1, put it into a jug, and power the pumps for a couple seconds, and verify you get a STRONG stream of gas. As I said, it could be upwards of 1 gallon/minute, so you want a large container, and just a few seconds...

if you already did this test, I apologize in advance, I didn't go back and read all 4 pages of this thread :-/

 

Hate to be the one to deliver you the bad news but you have a bad wire harness my friend. Just because you think those wires never touched and car was running great before you worked on it does not rule out a bad harness. I can be perfectly healthy one day and then the next day whamo I have a heart attack. That's what happens with cars too...Also the harness wires may have been sitting in such a way that before you messed with the car and did all your work, were perfectly fine. Then you disturbed the environment and moved wires slightly and somewhere inside that harness where you cannot see the coating is crumbling and wires are bare this is most likely your case. Like I mentioned in my previous posts the 84's are notorius for bad engine wire harnesses. Volvo used an environmental friendly biodegradeable coating that breaks down over time and with the harness being so close to the motor if it's not taped up properly and secured properly to the firewall the heat kills it even faster. So if you see bare wires...you can stop all your testing because you are going to drive yourself nuts! You need to replace or repair your engine wire harness first and foremost. If you cut into the harness very carefully with a razor blade and remove the tape until you can expose the wire bundle you can inspected the condition of all the wires. Make sure none of the wires are bare and grounding out on each other and if they are which is likely repair as necessary. Now with this being said, it is a very tedious and without knowledge difficult job and really the whole harness needs to be replaced. To be perfectly honest you do not have enough experience or knowledge to be doing work on this car at all. You don't even know what a jumper wire is...Please I know you're low on cash but before you mess your car up even more than it is already have it towed to a Volvo specialist. The guys in this or any forum besides myself and very few others are not mechanics they are enthusiasts and diyer's just like you but have been either alive longer or have been messing with their own cars longer and surfing through the internet and forums and remembering what they did or repeating what someone told them to do. You are going to get incorrect information that will just have you chasing your tail I.e. an 84 240 DOES NOT use a crank angle sensor!! Only 240's from 89-93 use a crank angle sensor on the bell housing...84 uses a hall sensor on the distributor. I do applaude your passion and determination but you don't have the proper knowledge, tools, test parts or literature to be diagnosing cars. You don't work on your own teeth do you? Stop what you are doing, save your money and an invest in good mechanic that you trust. You will not only get back a driveable car but you will also learn and gain more knowledge. If you do miraculously get it started, I would still replace the harness because eventually it will leave you stranded and this time a lot further feom home. Good luck!

 

I agree that the wiring harness could be the culprit, but I'm not sure yet that I can agree that it is definitely the problem.

Thanks for all the help, but I'm going to proceed with FPR and ECR then see what I get.

After that, I just may pay to have the harness replaced, but it's too early to jump out of my seat.

 

I kind of doubt 1984 harnesses are available new. paying someone shop rates to do this sort of tedious and highly time consuming work of manually rebuilding new harnesses, recycling the connectors one at a time would be outrageous (around here, at least, mechanics bill $100/hour.... and I'm guessing this could easily be a 100 hour job).


volvoguy is right, if you're not a DIY type with electrical experience and a lot of time on your hand, you have a basket case.

 

eat my words. Tascaparts lists 9139217 which is the 'main' engine compartment <-> dashboard harness for a US model 1984 240 with the B23F engine, for.... $1300 list, $1056 discount. This harness goes all over the place, but it doesn't appear to include the injection wiring.

oh, then there's the ignition harnesses... lets seee... per Vadis (parts system), .... eeew, this is a bit confusing, there's about 40 choices... k, it might be 3515723, $500 or so.

seriously? if your goal is cheap transportation, and from what you said so far you have zero mechanical or electrical experience or understanding, basket case.

 

Here is an update just before I go into work for a few hours.

I took off the FPR, installed the new one and now the car barely cranked at first then the second and third try it doesn't crank only makes a slight noise and idiot lights come on , that's about it. I do still here the relays kick it though.

Did I do something wrong putting in the new FPR. Was I supossed to bleed something? I dunno, just throwing suggestions out there...

Anyhow, I am about to say to hell with it to this car and scrap her. I paid $700, I'll gladly take $300 or so.

First, I would like to get it back to at least cranking..
I just found a 1995 740 turbo that needs just brakes and interior cleaned badly. They are willing to take $500 as it runs but is very dirty inside.