rs250

Sorry to bump this old thread up guys but I have a quick question! When I ordered my 2003 I spec'd it with the block heater even though where I lived in did not get cold...hey it was cheap! Now, seven years later I am using it for the first time since I am now somewhere it actaully snows and gets well below freezing! I plugged it in and came back a couple hours later, stuck my hand down and felt the block and it was slight warm, no sounds but putting my hand over the top radiator hose I detected a slight vibration with a barely audible sound. Is this normal, it seems to work as it gave heat very quickly and wamed up quick in 49 degree weather. As soon as I unplugged it the vibration stopped. Is this warm water trying to make its way around, or just a normal by product of the heating element doing its thing?

Well no real need to change the fuse I guess, the original 20 amp one is in there and the truck fires right up as normal with the new pump...quiet as can be!! Pulling the bed to replace the pump HAS to be the easiest way, very simple job!! So, at least in my case a hard start and low pressure must have been a faulty check valve in the pump!

So just to reiterate, do I need to bump up to a 30 amp fuse now? Thanks!!

Funny that I come back to this tonight....well I have been driving the truck for months like this including some long over the road trips. Finally got tired of the wait to start so I have the bed off right now and am replacing the pump with a new GM unit tonight...it is probably ready even if the check valve is the only thing wrong as the truck just turned a 130K over the weekend!! So, here I am replacing the pump, which btw was making stranger noises the last few days, and I am bit confused. I see this came with a new plug to splice in the harness, ok, no problem but it says to toss the 20 amp fuse and replace with new one included in kit, except there is no fuse...so what does it need, a 30 amp one now? Is it drawing more power?

Hey all...I used to spend a lot of time here back in 03 when my truck was new but have not been on in some time and forgot my old info so had to re-register... I have a 2003 1500 with a 4.8L. I just did a major tune up @ 120K last week and about two days ago I started having the hard start issue...wierd since I just did plugs, cleaned TB and MAF and lots of other stuff...truck is babied and very well maintained, has been flawless for 5 years and a 120K but now this! I put a fuel press. tester on it today and it cranks up to about 50 or so but then bleeds down to zero VERY fast...less than a minute. Tried changing the regulator with a new one but still same thing...I should be getting 55-62psi I think and little to no leak down correct? Could this be my check valve in the fuel pump going bad? I also just replaced the fuel filter when I did my big 120K tune up, I think it was the third filter I have put on and also ran some Techron....I doubt this caused anything though...my fuel pump is original and has 3000 hours of run time. So my questions...is my fuel pressure bleed off due to a check valve in the pump assy. since I swapped regulators with no joy? Is my somewhat low fuel pressure a result of my pump getting old and weak (not 55-62 psi) ?? Thanks!