2000 5.3L 2wd won't start - strange one I promise

[ws6jay]

Hey guys, I'm hoping to get some advice on something I haven't checked already. Before I ramble on about the history of this truck let me start with providing the symptoms:

- Truck will turn over, but not start or even hint at starting

- I have fuel pressure at the rail 55-60psi if I remember correctly (brand new fuel pump installed yesterday, along with fuel filter)

- I have spark, verified by removing a plug wire, stick a screw driver in and it arcs to a ground bolt

- I have a code scanner and the truck isn't throwing any codes at all

- All under hood fuses have been checked with a multimeter, haven't been able to check door ones because it's on a 2-post lift and I can't open the door enough to check them. I don't see any labeled on the cover that stick out to me as something that would cause this.

 

So a brief history on this truck and why no suggestion would be a dumb one:

- Purchased this truck about 5 years ago with no engine or transmission just as a project to put it back together. Kid I bought it from had aspirations of making it a race truck then quickly realized he didn't have the money to do so, so he sold the engine/transmission, realized he couldn't afford to build a motor, and then sold the truck because parents had already bought him a new truck.

- I purchased a motor from a salvage yard with similar mileage (84k miles where the truck itself has 80k miles). The donor truck was in a wreck and totaled, I actually got to hear it run and drive (well it couldn't turn but it moved forwards and backwards just fine) before it was pulled.

- I never really got the chance to work on it over the years, or rather I never had the drive to work on it, until my 40x40 shop was just completed about a month or so ago. I dropped in the motor/transmission, wired everything up. Flushed transmission lines, changed transmission filter, changed oil/air/fuel filter, flushed the fuel lines (because they were left disconnected all this time), installed a new radiator (it was missing), and also replaced the fuel pump because the first time I went to fire it up the fuel pump wouldn't kick on.

- I've even tried another ECM because I had the one that came with the truck, and the one that came with the motor.

 

So that's where we are, I've triple checked to verify that all grounds are good and tight, all wires are plugged in, etc. I'm at a loss as to where to go from here, the only other thing I can think to try is some starter fluid to see if it at least fires up a little bit, hinting at maybe clogged injectors/fuel rail or something that would cause me to get fuel pressure to the rail but not in the cylinders. I am going to give this a shot tomorrow evening but if anyone has any other suggestions I'd love to hear them.

 

Thanks for any help! I'm at a loss!

[anumber1]

Perhaps a security fault. Outside of using, hqving a real expensice scan tool or cheap/free access to a tech2, perhaps check if the injectors are pulsing.

[bubbanbrenda]

ECM should be programed to your specific truck engine combination, it is a security thing. PIA. just my $0.02/

[ws6jay]

On the new engine's ECM it was gettin security lights like crazy, but after I swapped in the original ECM for the truck I'm not getting security light. I'll update this evening after I try some starting fluid, I don't think it's a injector issue as I can smell gas from all the starting attempts but I should know for sure with this test. If that doesn't work I'll see what I can do to get my hands on a tech2 or similar scan tool.

[rjgti]

if you have fuel and spark, then look at cam timing or ign timing

[00Silverado4x4]

Check your fuel pressure regulator? While the engine is off you pull off the vacuum hose and check for presence of fuel. If there is, you need to replace the regulator.

[ws6jay]

FPR doesn't have any fuel leaking out of vacuum barb. I tried with starting fluid today and for the first time it attempted to start, it fired but obviously didn't stay running. So I'm guessing I've either got clogged injectors or an electrical issue causing the injectors not to pulse. The clogged injectors seems a little far fetched for all of them but the rail lines were open for 5 years so who knows.

[ws6jay]

Well I'm pretty sure it's just clogged injectors and bad gas in the rails, the injectors are plum full of crap, you can actually scoop stuff out of them, can't even see what I assume would probably be some sort of filter inside of them. I'm going to attempt to clean them with carb cleaner tomorrow, then test them before putting it all back together. Will post back with the results.

[muddkatt]

Since it tried to run on starting fluid, and now you found the crud in the injectors, you should be good to go once you clean the rails and the injectors. I would not try to test them, just clean everything good, reassemble and see what happens. You might have to pull the injectors again to clean anything that washes loose after running it for a while.

[ws6jay]

Just wanted to post an update, I ended up just spraying out the rails and injectors good with carb cleaner, then flushed the fuel lines a bit while I had them disconnected by just flipping the key on and off.

 

It attempts to start without starting fluid but still no dice. I took it all apart again, and since I had an extra engine harness I just cut off a connector for the fuel injectors to test with. Soaked them in carb cleaner and was surprised at how extremely dirt they still were, it turned the carb cleaner solid black. I did that a couple of times until the carb cleaner would stay clear after soaking them.

 

Then I put some carb cleaner in the injector, grabbed an extra tire valve and drilled a tiny hole in the cap just big enough to stuff the carb cleaner tube through and maintain pressure, and pressurized the injector that way. Then bumped a 12v battery a few times with each one. About 3 of them started spraying a brown mess right away, I just kept spraying until it came out clear. Then I had 3 that wouldn't spray but each time I bumped it, black goo would ooze out of them very slowly, I just kept doing it over and over and wiping the gunk away until they started spraying and eventually sprayed clean. I have 2 that are completely seized up, I can't get them to do anything, I soaked them overnight, still won't even click when power is introduced. I even tried boiling them for 10 minutes, still not getting any activity at all out of them. I went ahead and ordered 2 remanufactured injectors that will be here tomorrow.

 

I'll slap those in with my other 6 known working injectors and I'm fairly certain it will start right up. Now if I could just find a place to get some decent seats for this thing i'll be done with it! The truck has NO seats at this point!

[James Hymel]

One time on my 2000 the small vacuum hose coming off the FPR there's a elbow connection. Well my hose was worn out I rigged it with electrical tape but I pushed the vacuum hose to far into the elbow fitting was hard to start. Pulled it slightly out and fixed problem. But I ended up changing the hose once I finally found one and the fuel pressure regulator.