Hey there. Brand new to forum and volvos. Been readn a lot and I think I'm on the right path with this.
Might be buyn this 88 740 non turbo from this guy for 300$. He is the original owner. 82k miles. He just put new exaust,intake gasket, and some intake plumbing on it. Ran great for last 6 months then cut off and wouldn't start. He took it to mechanic and then it would start. Mechanic couldn't replicate problem. Guy drove it home, then it wouldn't start next morning. So there it has sat for 2 months. I turned the key and couldn't hear fuel pump, so I cracked fuel line open at rail, and cranked motor with no fuel coming out.
Next, I pulled the relay and put jumper in place and instantly heard online pump work. Then cracked fuel line open at rail again, and baam, I got lots of fuel. Checked spark on end of spark plug wire and I've got spark.
Really don't know where to go from now, asking for some help. I take it that realay is bad? So i've ordered a new one. Thanks just try to get home so I can dive in

 

When you jumped the FP relay did you try to start it? If you have spark and fuel it should start unless the crank sensor is dead. Did you hear both fuel pumps run? Also did you find and try to see what the diagnostic codes were if any.

 

Yes, tried to start and would not start , just turned over. I know for a fact at least 1 pump was working, it was very evident, felt like it was rite under driver seat and I could hear it, and it pumped fuel out at rail. Guy did not say anything about codes, I presume it's obd1, if so , I'll get a reader for that, all I have is a obd2 for my rover.

 

You don't need a reader , it's already on the car. Go here and it will show you how to read them. Engine and OBD Diagnostic Codes

 

Thanks jagtoes , itll be a couple days until I get back to car, I'll post codes as soon as I can

 

No diagnostic port in front of shock tower . Only power steering reservoir. Have spark and fuel, plugs are gettn wet from fuel, both pumps working with jumped relay socket

 

Ok. With fp relay socket jumped, fuel is getti ng to rail. I hear hear and feel fuel in the return line from fuel regulator. Have spark. No dig port to check codes. Ends up it's a late 87 model. Does have a halls sensor.

 

You didn't find this little plug.

 

No, there is a big gray Harness plug, a small 3 hole plug just lying there by power steering revs, and a 1 hole plug hanging behind brake booster

 

How big should this test plug be

 

Mine was behind the strut for info

 

I know y'all are trying to help, but for the life of me , I've have searched every inch of engine bay and cannot find diag port. However I did induce some starting fluid into intake and it fired rite up, but only until starting fluid was gone. Possibly injectors not firing, or bad for? Should I hear and feel fuel pressure on return line from regulator?

 

This was a picture of it with it's cover off. It should be by the drivers shock tower closer to the windshield. If you have a local Volvo dealer or someone who works on them go see him.
So if it started then you have spark. You will now need to go through the fuel system. Check fuel pumps , fuel pump relay , radio suppression relay , fuses, FP regulator. You need to find the diagnostic port.

 

Maybe 1 1/2"x 2 1/2" x 1" deep. I'm still looking on the web to see if maybe the turbo's didn't get this system until later.

 

Ok thanks, Just a reminder it's not a turbo. I'll keep looking. Thanks again

 

OK if it is not a turbo then you will have the connector unless someone cut it off. Start reading this Part 1 -1988 Volvo 740 No Start Diagnostic Case Study.

 

If you have an '88 then you will not have the diagnostic LED on your car. 88 had the LH2.2 fuel injection. The diagnostic LED thingy started with LH2.4 - which was installed on '89 and later models.

 

Aside from styling, 1990 marked a number of mechanical improvements to the 740 series. The B200 and B230 motors received larger 13 mm (0.5 in) connecting rods. The 740 Turbo switched from the Garrett T3-series turbocharger to the Mitsubishi TD04 series, which offers quicker spool-up and better boost at low engine speeds, albeit at the expense of top-end performance. The electronic fuel injection system was upgraded from Bosch LH-Jetronic 2.2 to 2.4 (in 1988 for naturally aspirated cars, in 1990 for turbocharged cars). The newer fuel system offered onboard diagnostics, which are accessible from the engine compartment and require no special equipment. For 1993, the final model year for the 740, the mechanical engine cooling fan was replaced with an electric fan. The 1990-92 Volvo 700-series cars may very well represent one of the most reliable 4-door passenger sedans of its era due to a limited number of engineering limitations and solid build quality

 

Well at least I know I'm not blind. No use to keep looking for that then, thanks for the info. Finally got it back to my house where I have tools and a garage to work on it. Pulled the fuel rail all was super clean and injectors appeared clean as well, however with the key on, I DONT have 12volts on green lead of #1 injector as I thought I read that I should, also checked suppressor relay on pass fender and I DO have 12volts on red terminal , all of this is being done with fuel pump relay out because it is bad, am I going about this the rite way or not

 

Something else I noticed is that there's no pressure at fuel rail when I crack it open after sittn a day from cranking on it, maybe main fuel pump is bad not pressurizing system enuff. Just asking, because my rover holds about 37 psi for days. Also what's the easiest way to install a permanent gauge at rail, just a tee and gauge , just trying to do some diagnostics to get this thing running again