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Greetings
I m trying to get old TPI system to work. As long as i know the pressure in the rail must be 43 PSi. I have new fuel pump, filter, part of the fuel lines, injectors are cleaned and they have no leaks but i only get 35 PSI in the rail, vacuum disconnected and engine not running. I just hardwire pump. I opened regulator, membrane is okey and spring is not sticking. Is it possible that over the years spring pressure rate have decreased and i shoult just buy new, maybe adjustable regulator?
Greetings
I m trying to get old TPI system to work. As long as i know the pressure in the rail must be 43 PSi. I have new fuel pump, filter, part of the fuel lines, injectors are cleaned and they have no leaks but i only get 35 PSI in the rail, vacuum disconnected and engine not running. I just hardwire pump. I opened regulator, membrane is okey and spring is not sticking. Is it possible that over the years spring pressure rate have decreased and i shoult just buy new, maybe adjustable regulator?
New doesn't always mean good unfortunately. Yes, springs can weaken over time. At least you are hardwired so you know you should be getting strong voltage. There is no drawback to an AFPR, even if it ends up not correcting the issue, it can always be beneficial later. Given what you have said, I would suspect the regulator and if I ever change one, I always go to an adjustable unit.
I got my hands on service manual which have troubleshooting charts. I blocked return and still got 35 PSI. I unblock it and put it in generic gas canister. No fuel in return line and pressure still 35 PSI. Another thing manual says that pressure should hold after pump shut down. Mine goes straight to zero. All that means I have to drop axle and tank. One thing i can not check is to pressureize whole system and pinch main line to see if system holds pressure. I changed all rubber lines with stainless steel braided lines and pressfitted fittings.
With troubleshooting, regulator seems to be okey. Pump i put there is Performance Electric P240KC from Rokcauto. Problem might be in that cheap pump or with in tank connections.
I got my hands on service manual which have troubleshooting charts. I blocked return and still got 35 PSI. I unblock it and put it in generic gas canister. No fuel in return line and pressure still 35 PSI. Another thing manual says that pressure should hold after pump shut down. Mine goes straight to zero. All that means I have to drop axle and tank. One thing i can not check is to pressureize whole system and pinch main line to see if system holds pressure. I changed all rubber lines with stainless steel braided lines and pressfitted fittings.
With troubleshooting, regulator seems to be okey. Pump i put there is Performance Electric P240KC from Rokcauto. Problem might be in that cheap pump or with in tank connections.
Sucks when you get a new part that is defective.
Kudos to you for doing troubleshooting before throwing parts at it.
I don't want to hijack your thread, but I have the same problem on my 92. I can't get the pressure over 35 PSI. But everything is stock, stock pump, stock lines, everythin. New filter of course. Even with an AFPR I am not able to get it over 38 PSI. The car runs good, but I "feel" it has to have a bit more power. It's just a feeling, can't proof it. And my pressure also goes to zero immediately after shutting off the pump. Very interested in a solution here. I have to drop the rear end this year for swapping to disc brake rear end. That would be a great opportunity to drop the tank also. Is it possible that the in-tank-filter is clogged or is the pump just "old" after 28 years? Why does the pressure drop within one second?
I don't want to hijack your thread, but I have the same problem on my 92. I can't get the pressure over 35 PSI. But everything is stock, stock pump, stock lines, everythin. New filter of course. Even with an AFPR I am not able to get it over 38 PSI. The car runs good, but I "feel" it has to have a bit more power. It's just a feeling, can't proof it. And my pressure also goes to zero immediately after shutting off the pump. Very interested in a solution here. I have to drop the rear end this year for swapping to disc brake rear end. That would be a great opportunity to drop the tank also. Is it possible that the in-tank-filter is clogged or is the pump just "old" after 28 years? Why does the pressure drop within one second?
Bad check valve, different pump architecture, punctured pressure regulator diaphragm, etc. Generally speaking, all the filters should be replaced when a pump is changed.
I don't want to hijack your thread, but I have the same problem on my 92. I can't get the pressure over 35 PSI. But everything is stock, stock pump, stock lines, everythin. New filter of course. Even with an AFPR I am not able to get it over 38 PSI. The car runs good, but I "feel" it has to have a bit more power. It's just a feeling, can't proof it. And my pressure also goes to zero immediately after shutting off the pump. Very interested in a solution here. I have to drop the rear end this year for swapping to disc brake rear end. That would be a great opportunity to drop the tank also. Is it possible that the in-tank-filter is clogged or is the pump just "old" after 28 years? Why does the pressure drop within one second?
I don't want to hijack your thread, but I have the same problem on my 92. I can't get the pressure over 35 PSI. But everything is stock, stock pump, stock lines, everythin. New filter of course. Even with an AFPR I am not able to get it over 38 PSI. The car runs good, but I "feel" it has to have a bit more power. It's just a feeling, can't proof it. And my pressure also goes to zero immediately after shutting off the pump. Very interested in a solution here. I have to drop the rear end this year for swapping to disc brake rear end. That would be a great opportunity to drop the tank also. Is it possible that the in-tank-filter is clogged or is the pump just "old" after 28 years? Why does the pressure drop within one second?
Hi, my old thread but if anybody is thinking which pump to buy. Some of them might have quality issues. Replaced Performance Electric P240KC with Delphi FE0110 pump. Pressure is now good and whole system passes service manual troubleshooting perfectly.
