Yet another P0442 post...

[BaconBandage]

the vehicle: '05 TB LT short wheelbase, 4.2L, ~133k miles.

During the summer, it threw a P0455 code. Replaced the vent solenoid, all was good. No garbage in the line or solenoid filter, just the usual dirt. Now I have a P0422- it could've been there since the solenoid swap, but the truck wasn't driven much during the summer (it's primarily a winter/hauler truck). I did a smoke test through the vent line, and the intake tubing with a home built machine, and wasn't able to find anything. I also tested the purge solenoid, holds a vacuum fine, and clicks while doing a bench test. Truck drives fine. So is it possible that the purge solenoid could still be bad? And will the light shut off if I refill the tank? Just asking, as my code reader shows that the evap monitor is ready, and I'm due for an inspection sticker this month

 

[mrrsm]

I strongly urge that you visit a Local GM Dealership and Pony up the Bread for a Brand New GM OEM ONLY Gas Cap. Then Clear the Engine Codes and start/warm up the Motor while eyeballing the Dashboard for any CELs. If none prevail... then this simple Part Replacement should solve the P0442 Issue and let you sail smoothly through your next Smog Inspection. However, if the P0442 Code repeats, have look at THIS TV Thread for more possible solutions:

Diagnostic Code P0442

forums.trailvoy.com

 

[BaconBandage]

Oops, should have said that the unknown cap that was on the truck when I bought it, was replaced with a OEM cap when the P0455 popped up a while back. Also tried the old cap, and the P0442 came back with that one as well. I did look around the tank where the filler neck attaches, did not see anything that looked like gas leaking out of it- though the metal parts of the neck are crusty. Also have never smelled gas around the truck at any time. I'll take a look at the top of the tank with a camera in the next day or two, as long as the weather cooperates. Worst case, I get a rejection sticker and 60 days to fix/re-test.

 

[mrrsm]

As you "Sneak & Peek"... Keep an ABC Fire Extinguisher close at hand just to be certain of no Electrical Shorts, Sparking etc.

 

[BaconBandage]

Well, this doesn't look too good . The top of the pump has some crust too, but I've seen far worse here on GMTN and elsewhere. Think it's possible to leak around the fitting where it goes in the top, and not the elbow itself? I would think that if the elbow had a hole, I'd be smelling/seeing gas...

 

[mrrsm]

Jesus Wept... What a Hazard, huh? Really Nice Camera Work!

@MAY03LT covers the Fuel Pump R&R very nicely in this Video:

...and for the Later Model Trailblazers-Envoys with the different piping and Venting set ups:

 

[Mooseman]

Yes, it is possible for the top and/or pipe to rust through causing a leak.

 

[Maverick6587]

I agree with @MRRSM I would replace the fuel pump. If you don't smell gas when you are close to the top of the tank, you might be safe for a little bit without replacing.

From my experience of replacing it three times in about 6 months.... Do NOT buy Delphi or cheap aftermarket fuel pumps.

Buy an ACDelco or Bosch fuel pump. It's expensive but, worth the money to only have to replace it once. Just make sure you take the time to empty the tank remove all the debris that is sitting on the bottom of the tank.

Also, make sure you buy the plastic connector retaining clips along with the fuel pump. They are VERY time consuming to remove and you are very likely to break them in frustration. You'll save at least an hour by just breaking the fuel line clips with pliers or a screwdriver to remove them. Try your best not to break the 5/8 evap clips, they are very expensive. You might want to try and grab a few of those from the junkyard first.

The little ones are about $5 for a pack of 6.

Dorman Fuel Line Clip 800-023

Shop for Dorman Fuel Line Clip 800-023 with confidence at AutoZone.com. Parts are just part of what we do. Get yours online today and pick up in store.

www.autozone.com

There are larger ones used on the evap connectors. They are about $10 for 1 clip.
https://www.autozone.com/fuel-delivery/fuel-line-clip/dorman-fuel-line-clip-800-041/318899_812190_0

I'm sure you can find the clips cheaper on Amazon or some other online store.

 

[mrrsm]

And...

@Mooseman once suggested getting "The Black POR-15 (Paint Over Rust) Sample Kit and Treating-Painting the Upper-Outer Flange and Piping Areas of the Brand New Fuel Pump BEFORE its Installation" ... to prevent any further Rust Out Issues from accumulated Brown-Ice and Salted-Snow Collection on the Top areas of the Plastic Fuel Tank:

Robot Check

 

[BaconBandage]

Way ahead of you on the Bosch pump and the pack of clips! Ordered those, along with a handful of other parts. Hopefully I don't break any of the large clips, but I've got a couple local stores that have them in stock.

Also, make sure you buy the plastic connector retaining clips along with the fuel pump. They are VERY time consuming to remove and you are very likely to break them in frustration.

Which clips are you talking about? The fuel line clips?

Thanks for all the help/suggestions, I'll keep you guys updated.

 

[Maverick6587]

Which clips are you talking about? The fuel line clips?

Thanks for all the help/suggestions, I'll keep you guys updated.

Yes, the fuel line clips and the evap clips.

Good job on the pump brand decision! Good luck to you.

 

[BaconBandage]

Quick update- the pump was definitely shot- far worse than I thought. And now for a tip- if you think your pump is anywhere close to super crusty, get the EVAP hose set (p/n 15909856) and fuel feed line (p/n 15200097). The pump end of the hose ended up getting mangled while trying to pull a chunk of metal out of it, and the feed line seals looked iffy after I finally got it off the pump. Ended up getting both from rock auto. As for the clips, the large ones are sold in 2 packs, at rock auto anyways- the EVAP line set had them all already, and I believe the feed line did as well. It took about 100 miles and 15 cycles for the monitor to reset after resetting the CEL, but it has been cold here. All that's left is the AIR monitor, but I'm allowed one here in MA, so I can go get a retest on monday