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Won’t hold fuel pressure , won’t start, new spider , new pump
i need some help please , Fuel pressure acting strange.
key on ,pump primes, relay clicks , pressure goes to 50ish and then drops to zero,
replaced spider no change, replaced pump “Delphi “ then pressure climbs relay clicks and holds at 30ish.. now dropping to zero again,removing power to spider holds at 30 psi, Have tried 3 different fpr none make the 4.3 CPI blazer hold pressure. Anything at all would be very much appreciated
I went through three Delphi pumps, all from advance Auto, last year. Not a single one held pressure brand new from the box. The third one worked for 15 miles, and crapped out after two weeks.
I said screw the lifetime warranty, and ordered an AC Delco from rock auto. So far has lasted way longer than any of the Delphi pumps last year.
Don't know if that's your problem, but it's worth a shot
Thank you for advice mine is the Delphi from autozone. Is there a way to test pump to know for sure that you you know of please?
By chance do you think maybe the computer telling it to drain fuel somewhere ? I can not find any leaks and pump seems to climb to proper pressure.
also the new injector seems to spray allot into lower when key primed and also it drips from injector tips with electric disconnected from injector . But the old injector does not spray or drip.. when I rebooked that one back up, so old one is in now because does not drip. Is it supposed to spray allot and then drip out of spider do you know ?
So, first off. To check just the pump, you will need to separate the pump from the injector and regulator. You can either do this at the pump itself or at the fuel filter, whichever is easier.
You want the pump to go directly into your pressure guage. This tell you what the pump and only the pump will do. If this does not create 80-100psi, and hold pressure, the pump is not working correctly
As to your questions about the spider dripping fuel. No, there should be no leakage of any kind. If the poppets are dripping or leaking, the spider is bad and needs to be replaced
im going to drop tank in morning and pull pump and go have swapped to see if any changes at all and will post any new findings. And look into getting a Delco for he blazer
pics are of the test today swapping injectors and fuel pressure regulators. New holds none. Wire connected or not.
old holds none when wire on, off holds 10psi swapped fpr on side of old and holds 30
If the injectors themselves are leaking, why are you replacing the pump??!!
Have you checked the fuel pressure at the pump? Not at the service port by the intake manifold. By the pump itself. Until you have done that, you're throwing money at it.
The new eBay injector I bought “remanufactured” looked high quality/new.
put that in sealed it up with no luck.
opened it up , replaced FPR on side of spider. Thinking jus maybe fpr is making pressure drop.
but no luck there.
Today swapped around injector parts/ tested different things to see if any differences.
And found that the new injector sprays heavy and then tips all leak equally as pressure drops to zero very rapidly,and with electric off they don’t spray but all drip.
so put old injector back into the 93 4x4 blazer w vin 4.3 CPI.
and found that they do not drip with electric off and holds 10 psi swapped the fpr with one of the few new I have and holds 30 psi. But with electric connected to injector drains to zero. Pump is new Delphi get 50-55 at rail for few seconds relay clicks and drops.
i have no idea what to replace next. if both spiders are bad or just the new eBay spider that drips. Electrical?
Any ideas or test I can perform please let me know
going to go disconnect filter and test test pump from there problly tonight when rain stops
Idk if helps but I just bought it drove only twice. It sputtered last had to work pedal to keep from dying to get it home. Seemed to get worse when had idling in yard then it died and hasn’t started back. The guy I got it from has the plastic panels and wire harness cover in back of blazer as if someone was accessing the computer that is tucked up by passenger lower dash/foot area. Could computer do these things or does it seem I have a leak internally ,because have checked very close and don’t see external leaks.
I will check the pressure and post new , thank you to any who read
01-04-2019, 08:57 PM
Won’t hold fuel pressure , won’t start, new spider , new pump
