Hello all, while trying to find out why my wagon takes several seconds be fore starting everytime, i found out my car has 2 fuel pumps. One under the car below the drivers seat beside the fuel filter and one in the tank that seems to be dead. According to several wiring diagrams my car "Regina /Rex system" is supposed to have only 1, in the tank. Is this factory? a previous owners bodge? upgrade? what should i do? I'm having difficulty trying to find regina pumps from auto parts chain stores, unless i say my car is a 90/91 model.

 

Sounds like your car is Bosch and not Regina! Regina started in 1990, and has just one in tank pump. What makes you think you have a Regina? Best look at the coil: if it is normal, round one, it's a Bosch, if it is a weird square, finned job mounted on the driver's side, then it's a Regina. Post a photo if in doubt!

 

Big square ignition coil with built in amplifier attached on drivers side. no AMM on intake, MAP sensor in metal shield also on drivers side near the diagnostic interface. I know it sounds weird, i wonder if this is a early regina system or the previous owner kluged this together. I was going to put a amp meter inline with the fuel pump circuit to see if the pump is about to fail and noticed that the car was still running even with the pump fuse removed. and i mean i drove around the block to my surprise! i traced the inline pump circuit back to fuel pump relay and it connects like it should for a bosch system, fuse 11 is only for the tank pump and also the lambda sond heater.
At this rate i might have to rename my car the "Frankenwagen"

 

This sound interesting. I have never seen a regina in an 89 740 but as you say it could be a early 90. I am surprised you would have the 2 pump system and if so and it ran well before I would replace the pumps you presently have. The regina only has 1 FP in the tank so for someone to put in the 2nd main pump would be visible with wiring and fuel lines. Just for kicks please post a picture of the engine compartment.

 

Ask and you shall receive, i've included a partial scan of the builders plate, Is this a 89 or 90 model?
I added a full underhood pic as well.

 

Tenth digit of the VIN is a K, so it's an '89 according to the plate. 1990 have two big headlights, 1989 have four smallish ones, sealed beams. The photos show a Regina, so... I'd say that it's a Regina... I can't imagine anyone actually converting a Regina to partial Bosch but who knows? Anything is possible...

 

the single pump regina cars still have a fuel FILTER where the bosch main pump is.

but, both bosch and regina use the same fuel pressure and flow rates, so either pump configuration should work, just don't mix them (bosch main pump uses bosch booster pump).

I have heard/read that you can use the bosch in-tank-only pump from a late 960 or early 850 turbo in place of the regina pump. the same pump was used on late 960/s90/v90... I believe that pump is cheaper than the regina pump.

 

You CANNOT use 850 or 960 pump in a Regina! I just went through all that while searching for a less pricey Regina fuel pump. BUT, not inconceivable that some backyard "entrepreneur" did some mods along those lines. Anything is possible and hard to say for sure without knowing the history of the car. Also, this car is an '89 according to the VIN, and Reginas started in 1990. Who knows?

 

is that because the pump won't fit in the tank assembly, or what?

 

Well, the size is different, so it won't fit in the unit with the sender. Also, I believe the flow rate is different, the Bosch has another pump, a check valve, etc.

 

hello all again, i've spent a few hours searching the web again and i found a article from
https://www.volvoclub.org.uk/faq/EngineFuelinjection.html#BoschvsRegina

a persom named Chris Mullet/Chris Herbst wrote "Variable Fuel Pump Setups: Many Regina cars have only one main fuel pump which is in the tank and no under-car pump; this fuel pump is reputed to be not as high a quality as Bosch. However, some 1989 to 1992 cars have Regina FI and two fuel pumps (both in-tank and under-car) similar to a Bosch system. The fact that your car has only one fuel pump is NOT proof that it has a Regina system, as the exception above notes. In addition, later 940s have Bosch LH 2.4 FI systems but single in-tank Bosch fuel pumps)"
Now i have to try and figure out which pumps i have and which i need.

 

Well, I had heard of that but never seen it. But, well, OK... Now, I wonder if those are Bosch pumps then because there is no such ting as a Regina main under the car type pump. You have to get them out and compare--not a pleasant option!

 

as the volvoclub article says, there are regina/rex cars that have bosch 2.4 dual pumps. both systems operate 43-44 PSI, both systems need the same range of fuel delivery. turbos need more fuel than NA

I noted the regina book said the fuel pumps were rated at 2000 g/min at 43 PSI operating pressure. 2kg of fuel is 0.7 gallons or 90 fluid ounces.

so there's 4 sorts of fuel pumps.

1) non turbo bosch, with a low pressure feed pump in the tank, and a high pressure pump under the car.

2) bosch turbo, same as type 1 dual pumps but with more volume

3) regina rex, single high pressure pump in the gas tank.

4) 1994+ bosch single high pressure pump in the tank

 

OK, so the Bosch lift pump must be less efficient, smaller, than the Regina single in tank pump... To fix that one would have to add the main Bosch pump and assorted hardware like check valve, piping etc., wire it in. Then the sending unit would have to be from a Bosch car as well to make it all work right... Better to fork out the additional $50 for the Regina pump!

 

well i'm facing a dilemma either way i go, If i go with a normal regina fuel pump "one in the tank" i'm going to have to pull out the working inline pump under the drivers seat and replace the line that goes from the fuel filter to the fuel tank. If my system is the rarely encountered OEM "experimental?" two pump regina system, finding the exact regina in tank transfer pump will near impossible after 26 years. Plenty of normal volvo parts are being discontinued by volvo. It's looking like a Bosch transfer pump might be the less expensive, imperfect solution. next week when i get a chance i'll take pictures of the pump and see if there are any part numbers on the pump unit. mike

 

if its got two pumps, they are Bosch. use the Bosch 2 pumps from any year 940, should fit just fine.

the in-tank pump from a 2-pump system is completely different than the pump from a 1-pump system... its a low pressure high volume 'delivery' or 'feeder' pump, whereass the single pump system is a high pressure pump.

note that most all newer cars use a single pump in the tank.

 

Hello Again. Today i have replaced the in tank pump. It looks to be original it has a date code of 06-89 on the side of it But is not bosch, it is made by VDO pt#92151034 and volvo 3501928

i can't believe this pump has run 284000 miles who'd thunk it.

 

All I can say is I feel your pain, I read through, I was going to offer you the measurements, pics of the regina pump I just yanked and replaced, etc./recent experience of swapping my regina in tank pump, but it sounds like it's solved... I have a '94 940 but man, sounds like you've got one weird set up going on.

I'll be sticking to Bosch redblocks from now on methinks...

 

It really hasn't been much of a pain as i thought. I got the tank pump at a auto chain store and they gave me a airtex pump that fit almost perfectly. The intake was slightly larger than the hole in the cup it fits into, it required 30 secs of plastic trimming to work. It even looks like the original design.
I spent a few hours searching and figured out 1989 was the first year of the regina rex system. even most parts databases and ipdusa don't list regina rex for 89 . Oddly enough this system was a more expensive option as it got better fuel mileage than the bosch system. the other years they saved cost by using one pump in the tank.
I have found several the sensors , coils, coil pack and other parts used in GM cars so that saves alot on parts replacement. The ECU that will have to be found at the junk yard or by expending alot of money for a new or rebuilt one. I haven't been frightened away from my car "yet".
I like puzzles and i post all of my finds here incase anyone else runs into the same problem.

 

Now that you know, you are good! Just don't expect to go to any shop and not have to deal with a lot of questions, same for parts store--you have to ask exactly what you are after and not rely on the "experts" which is a good idea anyway.