Died and now won't start

[s-crazy]

Gotta problem.

I drive my SY only on the weekends and a couple of weeks ago when I went to start it, it started for about 1 second and then died. Now it just cranks and cranks and cranks and nothing.

I started the following diagnostics.

1) Checked fuses. All ok.
2) Check fuel pressure at the rail. ok.
3) Check for spark. ok
4) Checked for engine codes, No codes stored.

Check engine light flashes when ignition is on.

I ran another test to see if I was getting fuel to the cylinders, so I pulled a plug, had my buddy crank the motor, and after 2 seconds of cranking, the damn thing started. I was like whoaaaaa!!!!! I put the plug back in and tried to crank it, and it doesn't start.

Am I not getting air into the mixture??? What should I check?

 

[myclone]

Re: Died and now won't start

Pull the rubber elbow off the turbo and spray some ether (starting fluid) in the end of the turbo while your bud cranks it. If it starts then Id check the fueling side of the engine but if it doesnt then start checking ignition components since ign modules tend to die at random (even with the truck not running) and coils do go bad sometimes.

Of course this is assuming that a shop rag didnt get sucked into the intake system or varmits of some type building a new home in there. That would be an issue too.

 

[SY2932]

Re: Died and now won't start

Sounds like an ignition module to me #1048-2827 BTDT twice now.

 

[s-crazy]

Re: Died and now won't start

Hey guys, thanks for the suggestions. Sorry for the late reply, just got back in the Country.

Question? How would you test the ignition module to determine if it's bad other than replacing it?

 

[NecroWolf]

Re: Died and now won't start

Orielly's offered to test mine when i thought it went bad.

 

[gmcturbo]

Re: Died and now won't start

pull the coil wire going to the center of the distributor cap and connect a spark jumper to it and ground. if you got spark there your module, pick up coil, and coil are good. if not, get a paperclip and insert it on the negative side and positive side of the module at the weatherpack connector coming from inside the distributor . a scope would be best here but you can use a multimeter on the ac low voltage setting. look for voltage moving as cranking. if so pick up coil is good. then insert the paperclip to the negative side of the coil and to B+ and look for the voltage switching from ~0 to ~12. if no switching the module is bad as long as everything previously is good. if it is switching and youre still not getting spark the coil is probably bad. the only good way of checking the ignition module is by process of elimitation.

 

[s-crazy]

Re: Died and now won't start

Well I pulled the coil wire from the distributor cap and checked it using a spark jump tester and I've definitely got spark. The next thing I did was pull the rubber elbow off near the turbo, sprayed starting fluid in it, and cranked it, it started. It will run, but it dies out after it warms up and the idle drops below 1500 rpm. I can keep it running as long as I keep the throttle above 1500 rpm, but as soon as I let the idle down below 1500 rpm it dies. The other odd think I noticed was that I can restart it on it's own (no assistance from the starter fluid), but only If I just turned it off after it's been running. If it sits for a while I can not started with out the starter fluid. What would prevent it from getting the right amount of fuel during starting and/or causing it to stall below 1500 rpm after it's started? I also checked the air intake and filter and there's no air obstructions.

I checked the EGR valve and it's fine.

 

[s-crazy]

Re: Died and now won't start

Ok, she's starting to collect a lot of dust in the garage.

Since my last post, I've replaced the IAC since the symptons seemed to point to that component. I got it through Advance Discount Auto so I hope it's ok. I reset the IAC and she's still having problems getting started without the assistance of starter fluid. I have the idle adjustment screw cranked all the way in just so it doesn't stall. It will run all day long at 1500 rpms and I can rev it up with no issues. As soon as I back off the idle adjustment screw and it starts to fall close to around 1000 rpm, it stalls.

I finally broke down and bought a laptop and the Datamaster software. I got it hooked up and collected some data. I was wondering if someone could look at the data to see if they spot an issue. I get an IAC error, but I just replaced that sucker. Anyway, any help would be appreciated.

 

[Flyin Ryan]

Re: Died and now won't start

Did you try resetting the computer after replacing the IAC? if not the error code will stay until you do even if the problem's been fixed.. at least that's my take on it.

Also did you ever check your fuel pressure to rule that out?

 

[s-crazy]

Re: Died and now won't start

A couple of months ago when I replaced the IAC, I did reset the computer and the truck still showed the same issues. I didn't have the Datamaster available at that time and the battery has been very low from sitting. I will attempt to reset the computer again and then see if it clears the code.

I did check the fuel pressure at the rail and pressure is good. I'll give it a shot again and let you know what I find.


Thanks!