scared to drive it/please, help with advice...

[cfan10]

OK, what are the signs of a failing fuel pump. Yesterday I was on the HOV (Houston folks know) and it kinda died, noticed it would not pick up any speed...luckily I was near a exit, and was able to coax it off, I put it back in park and it started right up. Made it almost home and it did it again, but started right back up. Not sure if it matters but I did a plug change the day before, but the last two of the plugs closest to the firewall on passenger side would not come out, so there still in there. Does this sound like a fuel pump failure. Its been daily driven without any major issues. But this was downright scary. I'm ready to throw in a towel. As always thanks for your time, it is greatly appreciated.

90 suburban 350tbi (previous owner says he changed engine, and fuel pump) I have no way of knowing.

[cfan10]

Changed fuel filter to drive works one from advance, maybe a week ago.

[Bigstevex4]

If its never been changed any thing over 120,000 its possable. Ans souds like its apossability.

[hatzie]

Fuel pump and pressure regulator issues will show up with a fuel pressure test. You won't get anywhere without a couple fairly inexpensive diagnostic tools.
Get a GM TBI fuel pressure test tap that replaces the fuel filter temporarily for diagnostics.
Tool Aid TBI Fuel Pressure Test Adapter 37650...

And a fuel pressure test gauge... Like this one.
OTC 5630 Fuel Pressure Test Gauge
If you have below 12PSI then block the return line by carefully pinching the rubber return hose with a pair of needle nose pliers.
If the pressure builds up replace the fuel pressure regulator.

If it's still lower than 12PSI check for leaks between the sender and the fuel filter connection. If there are no leaks replace the fuel pump and tank sock... I've seen the steel sender lines inside the tank perforate from rust so pay attention when you pull it.

[rich weyand]

I would do one more thing before replacing the fuel pump, which is a major PITA.

Check the soft fuel lines and see how the rubber looks. If they are old, old, old, replace them before you dig into the fuel pump. It's easy, and those lines can deteriorate inside, giving you little flaps of rubber that block the line above some threshold fuel flow.

[SCOTI]

Originally Posted by rich weyand

I would do one more thing before replacing the fuel pump, which is a major PITA.

Check the soft fuel lines and see how the rubber looks. If they are old, old, old, replace them before you dig into the fuel pump. It's easy, and those lines can deteriorate inside, giving you little flaps of rubber that block the line above some threshold fuel flow.

x2.

The short 'pick-up hoses' that are submerged were deteriorated on mine so it was hit & miss on consistent fuel delivery (the driver side hose was split). Replace them w/new hose that is submersible rated for ethanol fuels.

I swapped in new pumps while doing the work as a preventative measure too. That backfired on me as one of the new ac delco pumps already died (approx 6months old).

[hatzie]

Originally Posted by SCOTI

x2.

The short 'pick-up hoses' that are submerged were deteriorated on mine so it was hit & miss on consistent fuel delivery (the driver side hose was split). Replace them w/new hose that is submersible rated for ethanol fuels.

I swapped in new pumps while doing the work as a preventative measure too. That backfired on me as one of the new ac delco pumps already died (approx 6months old).

New pumps don't come with Ethanol rated hookup hose?? Chinese manufacturing at its' finest.

http://www.youtube.com/watch?v=pQSDfChxJJ0

[SCOTI]

Originally Posted by hatzie

New pumps don't come with Ethanol rated hookup hose?? Chinese manufacturing at its' finest.
http://www.youtube.com/watch?v=pQSDfChxJJ0

I'm not sure....

When I researched it, the info I read said submersible hose would have the rating printed on the outside of the hose (much like fuel injection rated fuel hose). When I opened my 'Made In Mexico' AC Delco fuel pumps, there was no printed info on the hose included. It's possible it was a section of the hose w/o the printing but there was nothing to support that it was submersible/ethanol rated in the literature that came w/it so I purchased some for peace of mind.

[hatzie]

If it's not marked then it likely is not. It'll do what the hose in the video did fairly soon.
The stuff you're looking for is SAE 30R10 rated hose. It's submersion rated for Alcohol, gasoline, and diesel.

SAE J1527, J1527 Type A1, & J1527 Type B1 reinforced Marine fuel hose is not submersion rated but is good stuff everywhere else in the fuel system. I use it for older trucks and cars with carburetors and low pressure fuel injection like the GM TBI systems. SAE J1527 Type A1 hose has a fire resistant outer jacket.

SAE J1527 Type A2 & J1527 Type B2 is for vent lines only A1 & A2 can be used on vent lines.

[SCOTI]

Originally Posted by hatzie

If it's not marked then it likely is not. It'll do what the hose in the video did fairly soon.
The stuff you're looking for is SAE 30R10 rated hose. It's submersion rated for Alcohol, gasoline, and diesel.

SAE J1527, J1527 Type A1, & J1527 Type B1 reinforced Marine fuel hose is not submersion rated but is good stuff everywhere else in the fuel system. I use it for older trucks and cars with carburetors and low pressure fuel injection like the GM TBI systems. SAE J1527 Type A1 hose has a fire resistant outer jacket.

SAE J1527 Type A2 & J1527 Type B2 is for vent lines only A1 & A2 can be used on vent lines.

Bingo. I was going to try & pull up this info as I remember reading it & why I specifically purchased it. it's not cheap either.... I got a 1' section & it was like $30.

[hatzie]

Datasheet of sorts for the SAE 30R10 hose from Gates.
http://www.gates.com/products/automo...fuel-line-hose

Here's the Gates C5M fuel hose that meets SAE USCG J1527-A1
http://www.gates.com/products/automo...fuel-line-hose

I usually use Fuel injection hose clamps rather than the cheap Ideal Worm clamps for these small hoses. They're still removable, unlike the crimp on clamps, but don't damage the outside of the hoses because the inner sleeve goes all the way around the hose with no gaps to extrude the rubber through.

[cfan10]

Does a 90 suburban 350 TBI have a fuel pump fuse and a fuel pump relay? Thanks. I think if it is the fuel pump I'll just cut a small hole in the floor to access it.

[esbstuff]

If you keep the truck topped off and it runs ok, then its the fuel pump hose.

[SCOTI]

Originally Posted by cfan10

Does a 90 suburban 350 TBI have a fuel pump fuse and a fuel pump relay? Thanks. I think if it is the fuel pump I'll just cut a small hole in the floor to access it.

Uhmmm.... it won't be as small of a hole as you're making it sound.

[cfan10]

Lol I thought about that after. But why not...since this seems to go wrong a lot. Anyone have any experience with the Napa unit for $219? Thanks.

[hatzie]

My A1 VW Rabbit GTI had an access plate under the rear seat for the fuel sender. It was pretty big but it was under the seat. Darn handy when the sender died.
You can get 4" to 8" boat deck plates with screw in covers from West Marine. http://www.westmarine.com/deck-plates
I use them for antenna access plates in the interior ceiling of transit buses.
For a TBI Suburban that I intended to keep I might look into installing one. It'll be hidden under the cargo carpet or mat and no more pulling the %^#%$ fuel tank to access the fuel pump or sender.