95 3100 Starting/acceleration problems

[Luckymc420]

My DD 1995 3100 stock motor.

Starting having problem accelerating away from stop lights and signs. It would sputter and then kick in. A few times backing up it would stall out. Well after leaving the hospital last night I went to start her up and she was misfiring and sputtering. I got about 4 feet and she died. I got under the hood and pushed on the fuel pressure port and had gas. I also checked spark. While trying to crank it would sputter and die. I never did smell raw fuel. I checked some connections and such. As I waited for my dad to bring me the scanner and some tools I tried starting it again and it took off and I drove it home no problems.

Today. I went to the gym. No problems. After the gym started acting up again, but she started and sputter and such. When going into gear it really starts missing and choking out sometimes die. Basically when it has a load. After a little it would run decent at a higher idle. So I drove home popping it in N when at a stop. Once at my garage I changed out the spark plugs and wires. Changed oil. After that it still was acting up. I really didn't think that was going to fix it but they looked sad. So I checked the fuel pressure at the rail and prime pump pressure runs 20 Psi. I forgot when it starts what it runs at. I don't think it's much higher. I was being rushed by darkness. I started to troubleshoot low fuel pressure. Fuel filter is about a year old, but I am thinking about replacing it anyways. I pulled the fuel rail off and check for leaking injectors. All good. The GM manual says it should prime to 41 to 47 psi. I did the trouble tree that included blocking off the return line to the tank and putting power to the test port. 20Psi. I ohmed out the wire going to the pump to a ground and got 14.5. I have a used pump that came out of a Z26 and that ohmed out 20K. I also checked Active and history faults and nothing was there. Well some EGR faults.

So I guess is it poss. for a fuel pump to be weak. I have always seen them fail or work. Any ideas. I think 41Psi seems high but that is what the book says.

[3X00-Modified]

41 psi is not high that's what it should be. Pull the regulator vac line while running and see if the pressure is 41-45. Also the pressure regulator could be bad an not just a weak pump.

[Luckymc420]

I know I unplugged that vacuum line and no change in the way the car acted. I did not have a gauge on it though. The only reason why I don't think it's a fuel regulator is because I blocked off the return line and put 12 volts to the test port. Still only 20psi.

[ifixalot]

20 psi is too low, pumps have two stages, one can fail and cause low pressure.
It happens on high mileage fuel pumps.

[3X00-Modified]

We have a single stage fuel pump.

[Luckymc420]

So I did a price check. About 85 for a new pump. Doesn't come with a prescreen but not worried about that. I have two options Delphi or Bosch. The Bosch said it's a turbine pump.. It doesn't say the pump max pressure but that doesn't really concern me. Any thoughts on turbine pump? I'm gonna try a new filter before I do the pump but just preparing for a pump.

Bosch PN: BSH 69223
Delphi PN: DFP FE0077

[3X00-Modified]

I believe they are all turbine pumps but I could be wrong.

[Asylum]

Have a look on Rockauto.com

You can get a good quality pump for a less that $85. That said, I wouldn't suggest buying the cheapest. It's not a fun job.

And yes they all tend to operate the same way. If they want to call it turbine, so much for marketing.

[Luckymc420]

Rockauto is my first choice but since this is a time sensitive thing I need something today. I Googled both part numbers and can't find any psi or gpm specs. As far as the turbine pump deal I don't care. But i do think I'm going to get the Bosch one. It's around 85. I think your right Asylum that it's a market thing. Now that being said. Any good tips on doing these. It's a 95 and the tank has never been touched so I'm sure the bolts will be nice and rusty. I plan on spraying the crap out of it with Zep 45 but anything else?

[Asylum]

Rockauto is my first choice but since this is a time sensitive thing I need something today. I Googled both part numbers and can't find any psi or gpm specs. As far as the turbine pump deal I don't care. But i do think I'm going to get the Bosch one. It's around 85. I think your right Asylum that it's a market thing. Now that being said. Any good tips on doing these. It's a 95 and the tank has never been touched so I'm sure the bolts will be nice and rusty. I plan on spraying the crap out of it.l with Zep 45 but anything else?

Get all the gas you can out of the damn thing! Gas is heavy.
And lower it slowly til you get everything disconnected and be careful.
You may need new straps depending on how the rust issue is.
You will find out soon enough.

[3X00-Modified]

Straps are not available so try not to break them.

[ifixalot]

I admit never took a Beretta's fuel pump apart. But, I did take the fuel pump from my 1994 Lumina APV apart after replacing it and it was two stage. I took the fuel pump apart from my 1985 Turbo Regal and it was two stage.
So I felt pretty confident that the fuel pump in a Beretta is two stage.

[3X00-Modified]

What are you seeing that makes you believe its a two stage?

[Luckymc420]

Jskiguy. I will take some pictures for you of the new one so you can see. I also have never been into one.

Well just in case I need the straps they do have them. This is the PN I got ST52. Hopefully around 4 I will be in the garage if not sooner. I am going to get the pump and strainer first then start over of the low pressure steps.

[ifixalot]

"What are you seeing that makes you believe its a two stage?"

It's been awhile but on one end of the pump inside, there is an impeller that has straight fins
as the motor spins the fuel is thrown out by centrifugal force.
It then flows through the motor and into a second impeller with curved blades on the other end of the motor.
The fuel than flows out of the pump.
The armature shaft has two flats and the impellers slide over the shaft and have flats inside. On one of the impellers, I don't remember which, in the Turbo Regal, the flats wore off so that impeller did nothing because the shaft was spinning inside it and we only had about 18 psi.
So the first impeller on one end I consider is stage one and the second on the other end is stage two.