1994 Chevy C1500 5.7 TBI, won't start, I need help!?!

[moonpie41]

I have a 1994 Chevy 2WD C1500 w/ 5.7TBI

I parked yesterday about 5 minutes after starting and running absolutely fine.
I went to go to work this morning, and all it did was turn over, no go.

I haven't ever really payed attention before, but now I notice
I don't hear the fuel pump kicking on when i turn the key to the on position.

Well, I looked in chilton and figured out electrical circuit i think:
I believe i've checked every fuse under hood and under dash, except for the WHITE inline fuses,
don't really know how or where to check them.


So I went ahead and replaced the cheap fuel pump relay to be safe $10. Still no start.

So what should i check before pulling tank and pulling pump out + $50 for a new one?
Open ears and in need of el trucko back in action. Using wife's new car, yep, you know how that is.

[stumpuller454]

do you know relays well enough to "jump" them? could do this to see if you can hear the pump not running, you can also try giving the tank a good boot or 2x4 trick maybe pump is toast, if you hit bottom of tank it may become "temporarily" unsized and you truck may run, if still nothing your gonna have to check for fuel pressure at engine, someone may have to help me out hear as to the location of the test port but i`m thinking near the throttle body anyway, should have a shrader type fitting with a plastic cap kinda like your tires do, anyways check for pressure there, 50-60 psi with key on of coarse, if no squirt very likley to pump, isa good idea to check for power and ground at plug in to pump, (is very ***tty to get at), actually easier with tank out but, you know,...Well this may help you"if" itsa pump problem, let us know how you make out!!

[fbhart@wk.net]

my truck did the same thing at 40K, just after warranty ran out

no fuel pump noise, at that time I did not know I could hit tank a few times and might get pump to loosen and run one more time.

GM fix about $600 plus tow bill

GM shop manager told me to change fuel filter every 15K and always keep tank 1/4 full or more. The fuel in tank keeps the pump cool and if you let fuel level get too low, pump can heat up and dirty filter cause excess load on pump.

I had never let the tank level get below 1/8 level, so I believe GM shop manager was just blowing smoke.

However, from that time forward I always keep a rubber mallet in my tool box, if pump ever locks up again, worth a try.

Have a good day,

[jimbo543]

spray carb cleaner in the tbi throttle plates, if it starts you have
1. no injector pulse(no fuel)
2. low/no fuel pressure(pump,wiring,out of gas)

spray carb cleaner in the tbi throttle plates, if it does not start you have
1.no spark, b/o ign coil or coil wire
2.no spark, b/o dist pick-up coil or ign module
3.no spark, timing chain(dist not turning)

[moonpie41]

that boot test worked, to find out i disconnected fuel filter from line. Turned key on, no fuel came out, no pump turning.

I got the wife to turn the key on while i banged the tank with my mallet from underneath and it started gurgling up fuel. Turned key off, reconnected filter/line and fired it up like nothing wrong.

I shut off, and tried to restart....nothing...back to same old ****. So i beat again got some gurgle, then nothing. I think its toasted, got $50 master brand pump/strainer from Auto Zone.

So instead of fooling with tank straps/lines and filler/vent hoses. I'm pulling bed off truck by disconnecting the tail lights and 8 bolts under upper lip of C-Channel of the frame.

That way I just get to pump from the top. So far I've noticed that the spare tire holder makes it difficult to turn a breaker bar. Also the rear bumper upper support bolts are in the way of putting a socket onto the rear bed bolts, will need to pull out top bumper bolts, or use a wrench. Suggested 6pt wrench and lots of PBuster/WD40. Rusty and dried mud.

The bolts are 18MM and are screwed into the threaded holes on the bed itself. not too bad it appears from visual. Gotta be careful cause stepsides/fenders are fiberglass.
Thanks for your posts, will keep you posted on results if u want them.

[stumpuller454]

i have never pulled the box off to do a pump just beacause of the usual mud, rust, or snow that may be onit, not to mention stuff in the box, but i always had a hoist, but at least when your done it`ll will be easier next time!!!(:. i always thought of making a trap door when i get to do mine, my truck is ten years old and still hasn`t needed a pump yet, altough my fuel pressure is 2-3 pounds less than nominal, but i`ll change it when i get drivability problems, anyways good luck!

[keithr0005005]

well just for future reference when checking fuel pressure on a tbi (88-95) the fuel pressure should be like 12 psi i believe. 50-60 psi is for the vortec 350s. lol when i did my fuel pump i just pulled my bedliner off cut a nice hole in my bed, replaced fuel pump, tacked bed cut back down, caulked, and reinstalled bed liner. took approximately 45 minutes.

[o3shortbed]

ive never had good luck replacing just the pump. i do the whole unit. the pipes tend to rust then leak. if u drop the tank do it all. no since doing it twice

[jdfenske]

well just for future reference when checking fuel pressure on a tbi (88-95) the fuel pressure should be like 12 psi i believe. 50-60 psi is for the vortec 350s. lol when i did my fuel pump i just pulled my bedliner off cut a nice hole in my bed, replaced fuel pump, tacked bed cut back down, caulked, and reinstalled bed liner. took approximately 45 minutes.

any multiport injection requires the 60+ psi; regarless engine or how many cylinder. . i've seen race injectors require at least 120, espiecally the high duty cycle ones that need to held open for more then 98% of the cycle. injectors have quite a bit to do with tuneups. if for some reason your getting poor gas milage and everything checks out, and you got 80,000-100,000 in the injectors, replace all of them, not just one. worn injectors won't flag o2 sensors, computer just adjusts to compromise. i replaced all 6 in my little 94 dakota and dammn the difference. 1/4 less throttle and back to the 25mpg. mind you always hauling 1200lbs of utility topper/tools

the face of the valve that opens gets worn from opening/closing against the injector nozzle; and they end up shooting like a squirt gun, not spray a mist, it's not the fact it's leaking, or 'burning more fuel', , but you find yourself giving it more gas to get the power you need since your loosing the atomization of the mist to get that 'hot' burn to push the piston down

[gmctrucks]

Stumpuller454 good idea about trap door my question is how would you determine where to make hole with out messing up I just might do that before I get bed sprayed with bedliner? Thanks!