crank no start

[98vortec]

alright got 98 extcab shortbed with the 305 im getting a crank no start i got 55-60 psi of fuel press. at rail and got good spark and compression if i spray fuel into intake it start the n die... i did change lowwer and upper intake gaskets everything went good and everything plugged in. but before i change gaskets i put new fuel pump in to get truck running but after new gaskets now no start,,,

 

[east302]

Did you have this problem before the intake work?

With the starting fluid test, it sounds like a fuel issue. The fuel pressure spec is 60-66 psi and to hold for a few minutes. Does it hold pressure?

If it holds pressure and since you're so borderline (it could be an inaccurate gauge?) and have a new pump, I'd wonder if the VCM is firing the injectors.

You can test for power by disconnecting the main injector harness and seeing if you have voltage. With test light or multimeter to ground, probe the power feeds (pink wires) for each injector with ignition on.

You must be registered for see images attach

You must be registered for see images attach

To see if the VCM is grounding out each injector during cranking, use a noid light across the power and output for each injector at the main harness. A test lamp may do the trick as well. It should flash as the VCM grounds out each injector.

If those tests pass, then another way to see if it's firing is to disconnect the coil, pull the upper intake, reconnect the injector harness and pull each injector to see if it sprays fuel while cranking. I haven't done that before, but would guess that it's a fire hazard if you aren't careful.

Do you still have the old style poppet injectors or did you swap to the multiport style?

Did you reset the camshaft position sensor offset (CMP Retard) after reinstalling the distributor?


Sent from my iPhone using Tapatalk

 

[aaron33]

If it's not the fuel, go ahead and replace the key switch/ignition wiring harness. This is the connector and wiring that runs down your steering column. Mine failed too. It is connected to VATS and prevents the fuel injection from working. The sensor at the key is worn from 19 years of turning. It is not getting a strong signal. $100 repair. H
Hope this helps and is the same problem I fought with for over a year.

 

[Tom P]

I know the truck fires when you put gas to it, but how is it running when you do so? Stumbles? Or is it running normally for a few? The reason I ask, is because it sounds like if you replaced the intake gaskets, then you would have had to remove the distributor. Are you 100% sure you got it set to 1 on TDC? I think this is probably the most common issue when a distributor is pulled. It would explain why you have spark but no ignition. I agree your fuel pressure appears to be low enough to be a problem. You said you installed a new fuel pump? Did you change the fuel filter as well? A clogged filter can lower pressure enough to cause an issue. If the truck was running before you did the job, I do have a hard time believing, although its not impossible, that it can't be something simple that was overlooked.

Definitely run through east302's troubleshooting, but I'd double check everything under the hood while you're at it.

 

[superdave]

How was it cranking before you did the intake gasket?

 

[east302]

If it's not the fuel, go ahead and replace the key switch/ignition wiring harness. This is the connector and wiring that runs down your steering column. Mine failed too. It is connected to VATS and prevents the fuel injection from working. The sensor at the key is worn from 19 years of turning. It is not getting a strong signal. $100 repair. H
Hope this helps and is the same problem I fought with for over a year.

Did the "security" light come on when this happened?


Sent from my iPhone using Tapatalk