4th DSM, and aa question on fuel pressure

[3aG1e_7a1oN]

I've read the stock fuel pressure in a 1G Turbo FWD was around 37 with the vaccum hose sealed off. I bought this DSM with a galant 420a fuel pump in it. I read the fuel pressure for those pumps were around 47-50 psi.

My car ran great for a few days with that pump in it, but now I'm expieriencing some fuel problems. I'm going to buy aa walbro pump on friday, but my question is: how should my car be running with that particular fuel pump in it? I'm not getting efficient fuel to cylinders 2 or 3, and i'm thinking an injector may be clogged.

Any input would be great.

 

[VETTE_50_TH]

FIRST of all, the base fuel pressure is controlled by the fuel rail regulator, not by the fuel pump. A fuel pump can flow that much, but we have a 1:1 fuel reg, so that means if what youre saying is true, that pump could flow enough pressure for 10-13 psi of boost. Flow in lph, which is the most important, is a different story.

Secondly, how do you know that injectors 2-3 are clogged? Have you tried to start the car with the rail off and see fuel come out of it? Which Walbro pump are you going with? a 190lph pump should be fine with the stock reg, but you cant just throw in a 190 and call it a day? Answer those questions first.

 

[3aG1e_7a1oN]

FIRST of all, the base fuel pressure is controlled by the fuel rail regulator, not by the fuel pump. A fuel pump can flow that much, but we have a 1:1 fuel reg, so that means if what youre saying is true, that pump could flow enough pressure for 10-13 psi of boost. Flow in lph, which is the most important, is a different story.

Secondly, how do you know that injectors 2-3 are clogged? Have you tried to start the car with the rail off and see fuel come out of it? Which Walbro pump are you going with? a 190lph pump should be fine with the stock reg, but you cant just throw in a 190 and call it a day? Answer those questions first.

Thank you for the input. My spark plugs on 1 and 4 fire just fine. 2 and 3 come out looking white, and 2 looks a bit wet. I've used various sets of plugs. When I pulled my rail the first time, the o-rings were hard and felt like plastic. I am going to replace these tomorrow. I'm also going to remove all the unnecessary emission vaccum lines and only leave the ones I need, using the taboo guide. The vaccum lines on this car are messy and some of them aren't even connected anyways.

I am going with a Walbro 190LPH pump, it's ordered and being shipped.

I'll post my results once I finish with that.

 

[3aG1e_7a1oN]

Okay, I have replaced my fuel injector lower seals, and capped of the vacuum lines and the car is running slightly better. Before I couldn't go over 15 miles, but now I can go at full speed, however the car is still misfiring and stuttering.

It only misfires at low RPMS, when I rev it up at idle, it'll catch around 2k and stop misfiring and run just fine for 10 seconds.

I've tested the CAS, the injectors, and the fuel pressure regulator. When I pull the vacuum line of the pressure regulator, the idle does not change. However there is no fuel in the vacuum line, so I believe it is operating just fine.

My coil to the closest side of the firewall, is completely rusted out. It looks as if someone took a bite out of it. However I am getting spark on all four.

My next step is going to be a boost leak test.