Fuel Pressure From Hell
#11
07-15-2018, 06:17 AM
This post is over 5 years old so my memory is a little foggy on the matter. I do know, as mentioned above, that my stupid fuel pressure gauge was not reading right. So I actually did have the proper pressure. Also, I had the old (original) fuel spider in the car and I attempted to do a clean job on it by running fuel system cleaner through it. Long story short, I screwed up the spider and didnt know it so I think thats why the car wasnt starting. I went ahead and bought the updated spider and put it in and my car worked fine after that.
With that said, the problems you describe are nothing like mine. My car either worked or it didn't. Your car was running somewhat bad and unreliably. You will want to be real careful with those fuel pressure gauges. They dont always read accurately. Garbage in, garbage out. Personally, I would take off the connector right AFTER the fuel filter, have someone run the fuel pump with the jumper in the fuse box. If fuel comes blasting out, the pump is probably working okay. Be careful doing this test, fuel will go everywhere. It's not a definitive test, though, because if the little hose that connects directly to the top of the fuel pump is not tight, fuel will leak internally in the tank and you wont even know it. That could cause low pressure readings.
When you upgraded the spider, it should have come with the fuel pressure regulator so that should cross that one off in case the old one was causing low pressure due to leakage.
With that said, the problems you describe are nothing like mine. My car either worked or it didn't. Your car was running somewhat bad and unreliably. You will want to be real careful with those fuel pressure gauges. They dont always read accurately. Garbage in, garbage out. Personally, I would take off the connector right AFTER the fuel filter, have someone run the fuel pump with the jumper in the fuse box. If fuel comes blasting out, the pump is probably working okay. Be careful doing this test, fuel will go everywhere. It's not a definitive test, though, because if the little hose that connects directly to the top of the fuel pump is not tight, fuel will leak internally in the tank and you wont even know it. That could cause low pressure readings.
When you upgraded the spider, it should have come with the fuel pressure regulator so that should cross that one off in case the old one was causing low pressure due to leakage.
#12
07-15-2018, 01:10 PM
Thanks for replying John! Wow, I didn't realize your thread dated back to 2013. Glad you're able to update on what was the underlying issue though.
In my case, the 98 Blazer first died back in 2016 while coming home from work at 45 MPH. Happened all of a sudden while crossing railroad tracks. Towed it home and just as I'm doing now, checked Fuel Pressure with Auto Zone's OEM Brand Fuel Pressure Test Kit. It came with a lot of extra fittings but I just simply screwed on the end of the hose into the Schrader Valve and when priming the Fuel Pump, it showed Zero Pressure. So that's when I purchased a new Delphi Fuel Pump, AC Delco Fuel Filter, and AC Delco Fuel Spider that has a new Fuel Pressure Regulator attached as you mentioned. As I removed the old poppet style Fuel Spider, 2 out of the 6 poppets were clogged with brownish gunk. Upon initial start-up, it fired right up but what amazed me was that the Fuel Pressure Gauge still read Zero Pressure from the Schrader Valve.
Blazer ran fine for about 3 months but would always have a slight hesitation from a complete stop. Then as my emissions were due, it abruptly died again while going over an overpass in October 2017. I shut it off, and it started back up. But if my mermory serves me right, it was sputtering intermittently even with full acceleration. 'My gauge cluster lights were slightly flickering as well. It did throw a code of "Heater Sensor (Bank 1 or 2)" I believe for the Driver Side O2, but that was always on. I went through 3 Sensors (Denso, Bosch, and AC Delco) and the Code would reappear after a month or so. From my searching on the web, many mentioned it could be a problem in the PCM.
I'll check if any Fuel comes out from after the Fuel Filter. Also checking the Ignition Coil and Ignition Control Module. Hopefully I can fix this Blazer.
In my case, the 98 Blazer first died back in 2016 while coming home from work at 45 MPH. Happened all of a sudden while crossing railroad tracks. Towed it home and just as I'm doing now, checked Fuel Pressure with Auto Zone's OEM Brand Fuel Pressure Test Kit. It came with a lot of extra fittings but I just simply screwed on the end of the hose into the Schrader Valve and when priming the Fuel Pump, it showed Zero Pressure. So that's when I purchased a new Delphi Fuel Pump, AC Delco Fuel Filter, and AC Delco Fuel Spider that has a new Fuel Pressure Regulator attached as you mentioned. As I removed the old poppet style Fuel Spider, 2 out of the 6 poppets were clogged with brownish gunk. Upon initial start-up, it fired right up but what amazed me was that the Fuel Pressure Gauge still read Zero Pressure from the Schrader Valve.
Blazer ran fine for about 3 months but would always have a slight hesitation from a complete stop. Then as my emissions were due, it abruptly died again while going over an overpass in October 2017. I shut it off, and it started back up. But if my mermory serves me right, it was sputtering intermittently even with full acceleration. 'My gauge cluster lights were slightly flickering as well. It did throw a code of "Heater Sensor (Bank 1 or 2)" I believe for the Driver Side O2, but that was always on. I went through 3 Sensors (Denso, Bosch, and AC Delco) and the Code would reappear after a month or so. From my searching on the web, many mentioned it could be a problem in the PCM.
I'll check if any Fuel comes out from after the Fuel Filter. Also checking the Ignition Coil and Ignition Control Module. Hopefully I can fix this Blazer.
Last edited by Chevy_Blazer; 07-15-2018 at 01:21 PM.
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