aftermarket fuel pressure regulator options for TBI

[vipergtrdj]

anyone know if this is true? in terms of the cap and rotor - http://www.rme4x4.com/showthread.php?83862-TBI-Hesitation-at-WOT/page2&

my cap and rotor are new, and i changed out the fuel filter still only getting 7psi pressure. Last time I dropped the tank I noticed I had a bit of dirt in the bottom of the tank, and plan on replacing it, but I want to troubleshoot if its definitely the tank, or apparently the distributor ? Any help, I am lost at this point.

 

[woody80z28]

If the truck runs well, I still dont think that 7psi reading is accurate. This is the gauge on your ebay AFPR in the return you are talking about, yes? If that is the case, your gauge reading in the return will not change when you adjust your converted stock FPR.

For my gauge I used this adapter with a 0-30psi 1/8NPT gauge from Summit. I have a couple pics in my build thread.
http://rvmorsemachine.com/product.htm

Do you have any pics of your setup I could look at?

 

[vipergtrdj]

The gauge that I am getting the reading from is the one on my pillar that has the electric sensor on the feed line to the TBI. Its a glow-shift gauge, and I tested it on a carb setup and it reads accurate. The eBay AFPR is no longer in the system, I took that out when I put in the stock adjustable regulator. I am thinking of grabbing one of those adapters so I can put a mechanical gauge in next to my TBI unit.

The truck seems to run fine. I think the dirt in the bottom of the tank may be the issue - it clogged up the new pump shortly after I installed it, within a few hours of running it. I did not have money to replace the tank so I was able to get some of the dirt out, but there was still some in there. I do have the money to replace the tank now, so I will be ordering a new tank tomorrow - along with a new pump strainer, and another fuel filter. I read somewhere that the rubber hose going from the sending unit to the fuel pump can crack under pressure and cause low pressure in the system. Hopefully I will know more this weekend when I swap the tanks around.

 

[woody80z28]

I've seen a friend's car have an issue with that rubber hose swelling in the fuel and causing pressure loss. It seems strange to me that it could be running well at 7psi, but I'll take your word for it.

 

[vipergtrdj]

at 7psi, It runs good until I get on the highway and WOT it, then you can hear some pinging around 3k rpms. I have not gotten to plugging in the laptop and doing some logging, but I did pick up a new tank, pump strainer, another filter, and some fuel line to replace that short piece with. I got the fuel injection hose thats good for high pressure - so hopefully it does good. I plan to swap the tank tomorrow night after I get home from work - I need to get a pump so I can pump the good gas out, got half a tank in there (just filled up the other day :/ )

So you have never heard about the distributor causing the low pressure?

 

[vipergtrdj]

well I took out the electric pressure gauge, and I put in a mechanical one after the fuel filter (easy to access and check for diagnostic purposes). The gauge goes from 0-140psi and I tested it with 20psi of air, and worked fine. The mechanical gauge now reads 15psi, wether I have the stock regulator all the ways open, or half ways closed (supposed to be a 15psi spring). I put in the new tank, new filter, new pump strainer, and I replaced the rubber hose with EFI high pressure hose. I am going to check the voltage on it tomorrow and make sure I am getting the right voltage at the pump. I ordered the pump which you recommended, and its supposed to be good up to like 40psi right?

Any ideas why my pressure is stuck at 15psi? I am tempted to try replacing the pump (maybe a bad pump?) .... Since I got the mechanical gauge in I feel that my pressure seems like its stock, altho I have a hick-up at idle again, but not as noticeable as it was before with the old pump.

 

[Joesgarage]

Have you tryed to reset the IAC and TPS? might help the idle problem.
http://www.thirdgen.org/tpimod2
Steve

 

[vipergtrdj]

Have you tryed to reset the IAC and TPS? might help the idle problem.
http://www.thirdgen.org/tpimod2
Steve

Yes I did that this morning but I think I am running lean at idle with all the mods, so I am logging it tomorrow am from a cold start and going to adjust the fuel. Right now if I cycle the pump on and off, and try starting it a few times, and let it stall, it will then start. Idles rough but then smooths out after a couple minutes.