Okay- I know there’s a lot of crank, no starts out there. I’ve got mine narrowed down. Just looking for some help with diagnosis.

Some background. This was my old man’s last truck. 1992 Pickup. I got it with a blown headgasket. It ran when I got it.

5 years ago I pulled the engine and was simply going to do an engine refresh and be on my way. Well I exposed a lot of rust on the frame and body.

Fast forward… truck went down to the frame. New fuel tank and pump,fuel and brake lines…New cab and bed… it’s been a long road.

Engine is back in. It WILL fire with starting fluid. Engine has good compression and oil pressure. It obviously has spark and air.

I primed the fuel pump with the diagnostic box and confirmed fuel at the filter in the line.

Installed a new MAF “OEM from EBay” as mine was damaged during removal. I am waiting on a new hose to connect into throttle body. But the MAF is connected.

I do not have the Injector Cold Start Sensor hooked up, as the connector was damaged as well. From what I can gather, that shouldn’t prevent it from firing through. I did order an OEM from eBay. Am I wrong in my assessment?

Questions-

I am 90 percent sure my vaccum hoses are correct, however are there any of them that will prevent it from running that I should check? I know I still have the charcoal box lower hose to get a few others like the 4x4 lines.

I did not take the fuel rail off the lower intake when I refreshed the engine. Could 5 years of sitting cause my injectors to clog?

What’s the easiest way to check if the injectors are working correctly?

What else am I missing??

 

Multimeter/test light while cranking would be the best way to test your injectors while cranking. That one in the front on the drivers side is possible to unplug just barely.

in my experience, 3.0 will work without vacuum stuff and cold start injector.

Otherwise you’re probably close to figuring this out. At least it’s not spark problems. Maybe try undoing the fuel feed at the rail to see if fuel comes out where it’s supposed to be. If not that then bypassing the fuel lines with a length of regular hose and a hardware store banjo bolt? It’s possible there’s a clog stopping fuel.

if you’re able to determine no clog for sure and you definitely have a working pump and injectors are pulsing. it’s time to pull the injectors out.

 

Don't disconnect a fuel line. Those pressurized lines are joined with crush washers (one-time use) which have to be replaced every time.

Instead, disconnect the low-pressure rubber fuel return line at the FPR. Use a 1/4"-6mm vinyl hose to a suitable container, and run the pump with the FP-B+ jumper. There is no spec, but I get 1/2 liter/min. If you get a lot less than that, you could have a clog or a weak pump.

While it will run without a lot of the vacuum "stuff," be sure that all vacuum leaks are covered. Otherwise, you'll lean out the fuel mixture and it can't start.

 

Alright- so I got a test light on 2 different injectors.

I have power to both wires on the injector with the key on. I also have constant power to the injectors while it’s cranking to both lines as well.

I gotta get my multimeter back from a buddy, but should those injectors be getting constant power? I thought they would be pulsing with the ignition timing.

 

Constant power on both doesn’t sound right to me, then again I haven’t done injector diag on my 3.0 in a few years.

I know they get constant key on power no matter what and that the ground is what pulses direct from ecu. Past that if you don’t have the ground pulsing the issue lies in the wiring harness or ecu most likely.

 

Injectors have constant power when key is set to run.
Injectors pulse when the ECM intermittently grounds the circuit.(s)
Not sure if all injectors fire simultaneously, or each bank separately.

 

So I got my new Cold Start Injector installed today and got all my air intake hoses hooked up and sealed.

Same deal. Crank, no start.

I pulled a plug and I have zero gas smell coming from the spark plug.

At this point I am guessing my injectors are clogged after sitting for 5 years. It’s just hard to believe all of them would clog so badly that I can’t get even a single cylinder to fire.

 

Quick update. I ran a line from the fuel return to see how much flow I had. I jumped the fuel pump in the diag box and let it run for 2 minutes. I had zero fuel come out of the line.


I knew I had fuel before the fuel filer on the frame rail, but hadn’t tested up to the injectors.

 

Fixed!

Well… it did had fuel at the filter. It must have clogged shortly after it started pushing fuel.

I had a clog somewhere in the pump/tank lines. Pulled the pump out and cleared it. Dropped it back in, primed the lines and she took right off.

Got a coolant leak I need to chase down.. but she’s running, for the first time in 5 years.