fuel tank clean, clean fresh fuel, new injectors, IAC and throttle body cleaned, new fuel filter --have not check fuel pressure..

car has hard start, like a flooded engine, starts on one or two cylinders, when warms up runs better.

slowly push accelerator car will RPM, but quick WOT engine stumbles exactly like an carb engine with no accelerator pump.

drive car and runs rough, 'pump' accelerator pedal and engine will RPM and somewhat drive normal. --have not gone over 30 mph (residential streets)

trans shifts and seems to work correctly.

no check engine light..

 

It sounds like it could be a fuel problem to me, at least from the symptoms you're describing. Your first step should definitely be getting a fuel pressure reading. You can rent a gauge at your local parts store, but it's pretty pricey. I paid over $100 to rent it, but the good thing is they give you a full refund after you return it. Just make sure you get it back to them in time, or they keep your money. Anyway, I don't remember what the exact fuel pressure numbers should be, and you didn't say whether your engine is tbi or tpi, the tpi has a significantly higher pressure requirement. If it's tpi there is a schrader valve to just hook up a gauge to, if it's tbi you would need to set up an inline gauge. Never done that before, so you would have to do some research if you don't know how.
Also check your spark plugs. I had a similar problem to this on my Suzuki, turned out to be a combination of low fuel pressure and fouled plugs. Would do alright as long as I didn't get on it hard, but if I punched it, it started stumbling and wouldn't rev like it was supposed to till 2500 rpm. If your plugs look bad, or even just haven't been done in awhile, I'd probably just go ahead and do them, cap and rotor, and plug wires if needed. Relatively cheap pieces that can work wonders for problems like this. But fuel pressure test first, don't go throwing money at it till you've done diagnostics and at least narrowed down what could be wrong.

 

I have TPI written in the heading...

but, going to check fuel pressure this morning as I went and got a tester last night.

I talked to the original owner of the vehicle, as I just bought it last weekend, and he said he replaced the injectors/pump/and filter roughly 10 months ago as the car has been sitting for some time.

i'll post back once I know more.

FERVERNT thanks for the reply

 

Yeah sorry about that I completely missed it. It could also be the regulator if he didn't replace that. Keep updating on here, I'll help as much as I can. Also, you should check the engine codes anyway, see if anything pops up. I had that happen once, light didn't come up but it threw a code for the MAP sensor when I checked it.

 

about 10pis while cranking, and 15-20 while running.
tried unhooking regulator while running and no difference, will replace pump and check back in..

 

Sounds like the right course of action.

I just went through dropping the tank. It's not THAT hard; my aftermarket exhaust gave me the most issues as it wouldn't drop down far enough. Cut it off and re-welded it. Everything else was pretty strait forward.

It's a good time to check your filler neck for leaks, too. That is why I was drop my tank as I was replacing it.

 

removed carpet found this awesomeness....

went ahead and removed old pump, installed new pump, starts runs near perfectly.

now to remove valve cover and investigate the lifter noise/tapping that started. Didn't make any noises until the oil change. must have flushed a piece of something into the lifter maybe causing it to stick. bummer...

 

removed valve cover and Number 3 cylinder has a very loose rocker, a bit of inspection and the stud is pulled out of the head by 1/8 inch or so..

not sure why this would happen, never seen a stud pulled out, but I have heard of it.

hope it didn't kill them cam, or worse....

oh, motor runs nice and smooth, had zero noises since I got it running, turned the engine off one night, came out the next day turned it on and the ticking was there. ran it for a minute or so to identify the location, added some 'sea foam' to see if it would clear up the sticky lifter, then pulled the cover and seen this.


fun, fun fun...

 

My worst nightmare.. the dreaded lazy-mans cut-out.

 

 

so one rocker arm stud on both heads pulled out an 1/8 of an inch. So I adjusted the rocker arm and the motor runs perfect, smooth, quiet, just as sweet as can be. The fuel pump really did the trick, this car spins the dry-rotted rear tires like it's on ice...

The concern I have is obviously the 2 rocker studs the pulled from the head. I don't want to pull the heads just yet to machine for screw in studs. with 148K on the clock, I might not even mess with the factory heads and just install some new ones. I haven't checked to see if the late model vortec heads are a direct swap, or if i'll some cheap aftermarkets.

todays new heads are cheap enough it's not worth rebuilding a set of stockers...

 

for an update, have had zero issues since readjusting the valves. nice quite smooth running engine.

had the ac converted to 134, and gets 38 degrees out the vents..

 

another update, got about 400 miles on the car now. runs perfect, hasn't skipped a beat, had to replace alt/water pump, but that was to be expected on a vehicle that sits.

over all been fun.. soon to start the body work and paint