Wont start, Started troubleshooting tonight

[Don W.]

Re: Wont start, Started troubleshooting tonight

Along with everything else you're checking. Do a fuel pump test. You can energise the pump with a test connector you'll find near the dist kinda toward the pas side. Looks like a female elec connector with nothing in it. Put 12v into that and you should here the fuel pump run. (I'm surprised no one, including myself hasn't mentioned this yet.) Assuming you do hear it run then check again buy just turning the key on. Pump runs for 2 seconds when key is first turned on.

 

[boosteds10]

Re: Wont start, Started troubleshooting tonight

Well I def can hear the pump prime. Just did a fuel pressure test off the schrader on the rail. 10psi with the key on..no good right? Pump? Regulator?

 

[Don W.]

Re: Wont start, Started troubleshooting tonight

Squeeze shut the return line, I'm serious. If pressure come up it's the regulator. If it doesn't it's the pump

 

[boosteds10]

Re: Wont start, Started troubleshooting tonight

What about the fuel filter?

 

[Don W.]

Re: Wont start, Started troubleshooting tonight

With engine not running? Possible but unlikely because, unless it's totally clogged, and even then pressure would build as I believe there is valve in the filter that open when the restriction become to great. If you don't know when it was changed then prolly a good idea to change it anyway.

 

[boosteds10]

Re: Wont start, Started troubleshooting tonight

yeah Im gonna change it tonight and probly just order a walbro pump and an adjustable FPR. Part of the mod list anyway so I might as well just do it now.

Hopefully thats the only thing wrong

 

[sly dvl]

Re: Wont start, Started troubleshooting tonight

If the fuel pump is running for a few seconds after cranking (which he stated it was) then the ign. module is doing its job.
Bad Ign. module means no ref. pulse and no fuel pump (except for the 2 second KOEO prime).

 

[SY2932]

Re: Wont start, Started troubleshooting tonight

If the fuel pump is running for a few seconds after cranking (which he stated it was) then the ign. module is doing its job.
Bad Ign. module means no ref. pulse and no fuel pump (except for the 2 second KOEO prime).

I still wouldn't rule it out because when I had to get my truck flat bedded home (truck died at the bottom of an off ramp on a major highway) last Thanksgiving, the ignition module was dead. It checked out bad at Autozone and after I installed a new one, it fired right up. The fuel pump was working when I was trying to get it started too (I stll have the factory wiring, no exotic setup on my fuel system and stock ECM). I have had to deal with ignition module problems on every GM that I have ever owned... Right now, I'm on my third one in my syclone.

 

[sly dvl]

Re: Wont start, Started troubleshooting tonight

The Ign. module has two jobs.
1. Send a distributor ref. pulse to the ECM so it knows the engine is rotating.
2. Below 400 RPM the module controls when the coil fires (above 400 the ECM takes over).

If either one of these circuits fail then the truck won't start. Since the fuel pump runs and there is spark I strongly doubt it's the mod.

Mike, what coil are you running? What wires? If you've gone through 3 GM modules I'd be looking for a reason that they keep failing. :2cents:

 

[SY2932]

Re: Wont start, Started troubleshooting tonight

Mike, what coil are you running? What wires? If you've gone through 3 GM modules I'd be looking for a reason that they keep failing. :2cents:

For the past three years, I have been running an OEM GM ignition coil. I tried to use a MSD Blaster coil briefly with poor results prior to that. Wires are the tried and true 8MM Taylor Spiro Pros. The three ignition modules are just the kind of "luck" that I have with my truck and vehicles in general as far as that goes

.

Anyone who knows me personally knows how anal retentive I am about my truck. Everytime the ignition module gets replaced, the top of the distributor and and the bottom of the module get wiped clean with technical grade alcohol before applying the heat sink grease. And the screws that hold the distibutor cap on get synthetic grease (use a toothpick to get the perfect amount) to keep them from seizing.

The kicker is that I only drive my truck 6-7 months out of the year averaging less than 3,000 miles per season. Passes at the track can be counted on two hands (if I make any at all). The truck is garage kept and covered at all times. My truck has an EASY life compared to most but it still breaks. I can't put into words how aggravating that is. With the cost of gas what it is these days, I'm glad that I have other hobbies that don't cost a small fortune to enjoy

.

 

[sly dvl]

Re: Wont start, Started troubleshooting tonight

Anyone who knows me personally knows how anal retentive I am about my truck. Everytime the ignition module gets replaced, the top of the distributor and and the bottom of the module get wiped clean with technical grade alcohol before applying the heat sink grease. And the screws that hold the distibutor cap on get synthetic grease (use a toothpick to get the perfect amount) to keep them from seizing.

My God! I think I've just found my long lost brother! Someone who's as anal as I am, and has the same luck too. :rotf:
Glad I'm not alone... :tup:

 

[SY2932]

Re: Wont start, Started troubleshooting tonight

My God! I think I've just found my long lost brother! Someone who's as anal as I am, and has the same luck too. :rotf:
Glad I'm not alone... :tup:

Heh, I'll have to buy ya a drink at the MI meet

? I even amaze myself how much time that I can spend doing so little

. At the top of the list is removing the entire dash out of my old daily to clean the *inside* since it was "mouse house" before I bought it. Must have used about 250 Q-tips cleaning out all the nooks and crannies. Had a kid turn in front of me a few weeks later and it got totaled. That's 60 plus hours of my life that I will never get back

...

 

[sly dvl]

Re: Wont start, Started troubleshooting tonight

Heh, I'll have to buy ya a drink at the MI meet..

I'm gonna take you up on that offer. :tup: Just drive carefully, Mike.

 

[boosteds10]

Good News

Good News

Well after waiting for parts and such, new pump and regulator did the trick...dont know which one it was, dont really care, runs great now and I got to upgrade to the AFPR and the walbro pump.

Lookin forward to throwin some more mods on in the near future.

Thanks guys