Crank but no start-please help

[Blackie]

My 2004 Yukon with the 5.3L with 210K on the odometer died on me 2 weeks ago when I had the A/C full blast on a hot day. It started idling rough at the stop light so I pulled over and it died. It started up after an hour of multiple start attempts and seemed to drive home fine. Two days later I went to Autozone for them to test my battery and alternator. Guy had me start it with his tester connected to my battery and his tester said my starter was the problem (right after he had me start it!). While his tester was connected I told him it dies under full load so he had me turn the A/C on full blast and it died within 10 seconds. Had to have the truck towed home. Since then I've replaced the alternator and the battery to make sure it wasn't one of them. When you try to start the truck, you hear the starter crank like it should but it won't start. At first I thought it might be fuel but the weird part of it all is my gauge needles don't move at all like they do when you turn the key to "on" or "run" positions. Could it be a fuse or relay? Could it be the passlock system not allowing the start procedure to take place? I'm at a loss and hoping someone else may have had this problem in the past and has a solution?

Thanks in advance for any help/advice offered.

 

[Fless]

A couple of things to check: rent the fuel pressure gauge from the parts house and do a key on, engine off pressure test. Post results here.

Check and clean the grounds that are under the driver's door hinge, on the body mount on the frame, just behind the left front tire. One of those is for the body control module.

Apart from that, get someone to diagnose it before parts are shot at it.

 

[OR VietVet]

What @Fless said. Gotta start with basics. Spark when problem occurs? Fuel pressure when problem occurs? Cranking rhythm sound correct? Sounds like it is not handling a load and that may well be the fuel pressure.

How old is this contraption? https://www.rockauto.com/en/moreinfo.php?pk=360092&cc=1425327&pt=6200&jsn=894

 

[Blackie]

A couple of things to check: rent the fuel pressure gauge from the parts house and do a key on, engine off pressure test. Post results here.

Check and clean the grounds that are under the driver's door hinge, on the body mount on the frame, just behind the left front tire. One of those is for the body control module.

View attachment 406006

Apart from that, get someone to diagnose it before parts are shot at it.

Thanks for the reply @Fless. I just removed those 2 wires and cleaned them real good as well as the frame they were mounted to with no luck. Something I forgot to mention in my first post is that 2 weeks before my problem, my gauges in my cluster intermittently did not work. The truck would start up fine but none of the needles, PRND, or information display would work. Sometimes they would never come on during my drive and sometimes they would randomly come to life while I was driving. All the backlights/blinker lights in the cluster would work fine though. That is one of the reasons I am leaning towards an electrical issue over a fuel issue. I will try to get over to a parts store to rent the fuel pressure gauge later today to give that a shot.

 

[Blackie]

What @Fless said. Gotta start with basics. Spark when problem occurs? Fuel pressure when problem occurs? Cranking rhythm sound correct? Sounds like it is not handling a load and that may well be the fuel pressure.

How old is this contraption? https://www.rockauto.com/en/moreinfo.php?pk=360092&cc=1425327&pt=6200&jsn=894

Thanks for the reply @OR VietVet I replaced the spark plugs and wires about 3 months ago so unless I got some bad ones they should be good. I'll have to get the fuel pressure gauge Fless mentioned to test that. The cranking rhythm sounds like it always has in the past, it just won't fire up. My older battery was only showing 13.2 volts under load so I replaced it with a new one. I can't get a load test on the new battery since the truck won't start but the battery is showing 12.6 volts with my multi meter connected directly to it.

 

[strutaeng]

You probably have several issues going on.

1.) The cluster may be going bad (some solder reflow fixed the odometer on my 99 Silverado, although the 99-02 and 03+ clusters are different.)

2.) May have an intermittent fuel delivery problem. The commutators on the fuel pump motors start failing and sometimes they fail to start. So please invest in a fuel pressure gauge. $35. I can't tell you how many times I've had a crank-no-fire and a quick connection with a fuel gauge shows normal pressure: it ain't the fuel pump, so keep looking. It's shocking how some DIYers change a fuel pump without even checking for pressure! Continuing on this, check relays and power at the pump if the first test fails. Wouldn't hurt to replace the fuel filter if you haven't at some point.

3.) If the truck crank but doesn't fire, it obviously can't be the starter. Sometimes starters will start sticking and the engine won't crank at all. You can beat them with a hammer while cranking to get them to turn over. But it doesn't sound like this is your case. If it were to fail to crank, then you check with a test light (another must-have, underrated tool) to ensure you have power when the key is turned to crank.

4. Air and compression you only be suspect if the previous tests are all okay.

I hope this helps.

 

[Doubeleive]

verify grounds first this means not just the little ones, check the main ground off the battery to block & frame and block to frame
use a ohm meter

 

[Tonyrodz]

My 2004 Yukon with the 5.3L with 210K on the odometer died on me 2 weeks ago when I had the A/C full blast on a hot day. It started idling rough at the stop light so I pulled over and it died. It started up after an hour of multiple start attempts and seemed to drive home fine. Two days later I went to Autozone for them to test my battery and alternator. Guy had me start it with his tester connected to my battery and his tester said my starter was the problem (right after he had me start it!). While his tester was connected I told him it dies under full load so he had me turn the A/C on full blast and it died within 10 seconds. Had to have the truck towed home. Since then I've replaced the alternator and the battery to make sure it wasn't one of them. When you try to start the truck, you hear the starter crank like it should but it won't start. At first I thought it might be fuel but the weird part of it all is my gauge needles don't move at all like they do when you turn the key to "on" or "run" positions. Could it be a fuse or relay? Could it be the passlock system not allowing the start procedure to take place? I'm at a loss and hoping someone else may have had this problem in the past and has a solution?

Thanks in advance for any help/advice offered.

Any luck with your no start issue?

 

[Blackie]

Any luck with your no start issue?

Not yet. I ran the fuel pressure test and it was on the low side at 46psi. I took it to a small repair shop and they got 49psi on their pressure test. They said that is within range to start the truck so they don't think it's a fuel issue. They found that their was no spark at the coils. I replaced the plugs and wires less than 6 months ago but I've never replaced the coils. It's at the local Chevrolet dealer so they can diagnose what's wrong. Hopefully they will have something for me next week.

 

[Doubeleive]

Not yet. I ran the fuel pressure test and it was on the low side at 46psi. I took it to a small repair shop and they got 49psi on their pressure test. They said that is within range to start the truck so they don't think it's a fuel issue. They found that their was no spark at the coils. I replaced the plugs and wires less than 6 months ago but I've never replaced the coils. It's at the local Chevrolet dealer so they can diagnose what's wrong. Hopefully they will have something for me next week.

one thing that happens to these on rare occasion is the coil and/or injector harness develops a bad ground, unless it starts and dies right away within a second then it's proably not vat's, could also maybe be a problem with the harness at the ecm/pcm such as water intrusion or corrosion

 

[Tonyrodz]

Not yet. I ran the fuel pressure test and it was on the low side at 46psi. I took it to a small repair shop and they got 49psi on their pressure test. They said that is within range to start the truck so they don't think it's a fuel issue. They found that their was no spark at the coils. I replaced the plugs and wires less than 6 months ago but I've never replaced the coils. It's at the local Chevrolet dealer so they can diagnose what's wrong. Hopefully they will have something for me next week.

I doubt it's all, or even 1 coil. They all don't quit at once. If it was only 1 coil coil, you'd get a random misfire code for that cylinder--if it was cylinder 2 it'd be a P0302.
If it's no spark--I'm definitely no expert here--possibly could be a wiring issue. I can't wait to see what they find. Hopefully it won't be crazy expensive.

 

[Doubeleive]

running fine and dying under a load would point me to look for a poor ground, start wiggling wires and inspect all over, sometimes a wire harness rubs on something and wires get rubbed and break or are exposed and causes issues, sometimes a wire can break internally.

 

[Doubeleive]

for any one else you can always try to be preemptive and look under your hood and check all your wires and harness to be sure they are secured properly and not rubbing on anything over time wires droop, clips sometimes break and let the wires hang, engine movement pulls on them, always a good idea to take a close look at everything and adjust as needed

 

[Blackie]

running fine and dying under a load would point me to look for a poor ground

I did take off the grounds (except the one that's wedged between the engine and the firewall) as you suggested previously and cleaned the contact points good before reconnecting them and no luck. I believe it is a bad ground or wire that came loose but could not for the life of me find one!

 

[Doubeleive]

I did take off the grounds (except the one that's wedged between the engine and the firewall) as you suggested previously and cleaned the contact points good before reconnecting them and no luck. I believe it is a bad ground or wire that came loose but could not for the life of me find one!

the coil pack harness has it's own ground, so does the injector harness.

 

[lyncht1967]

If coils all arent delivering spark i would suspect a wiring fault in ignition coil circuit. most likely ground (g102 ground on side of engine is known for getting corroded and is the common ground point for all coils) or power but maybe reference low. all coils share a common wire for each of these three and an intermittent short in any one of them would take down all coils. Here is a good video showing this exact problem on a 2009 Sierra but GMT800s are the same configuration on coil wiring. You can skip to around 15 min mark for coil section. Shows how to test each wire.

 

[Blackie]

If coils all arent delivering spark i would suspect a wiring fault in ignition coil circuit. most likely ground (g102 ground on side of engine is known for getting corroded and is the common ground point for all coils) or power but maybe reference low. all coils share a common wire for each of these three and an intermittent short in any one of them would take down all coils. Here is a good video showing this exact problem on a 2009 Sierra but GMT800s are the same configuration on coil wiring. You can skip to around 15 min mark for coil section. Shows how to test each wire.

Thanks for the input lyncht1967. The truck is currently over at my local Chevrolet dealer. I talked to the service advisor yesterday. He said the truck is in the repair bay and the tech working on it is on vacation all next week! Luckily there's no rush on my end for me to get the truck back. He said with the bit of diagnostic tests the tech was able to do, he thinks the problem is in the passlock 2 system/module. At one point, I did get a code for the passlock system so it seems he is on the right track. Once I get more info and the truck fixed from the dealer I'll be sure to post what the problem was in the hopes it helps someone else in the future.

 

[Blackie]

So I finally got the truck back today. According to the dealer, it turned out the Passlock and the PCM modules failed and had to be replaced. So, $2,191.15 later my truck is running like a champ again!

Thanks to everyone who posted in efforts to help out.

 

[Tonyrodz]

So I finally got the truck back today. According to the dealer, it turned out the Passlock and the PCM modules failed and had to be replaced. So, $2,191.15 later my truck is running like a champ again!

Thanks to everyone who posted in efforts to help out.

Pretty expensive, but at least it got figured out. Strange, the pcm went bad on the pcm in my old 01 work van. It actually was the same condition--it would start fine all during the work week, but if it sat over the weekend it wouldn't start. Did your old pcm have corrosion on the wires? I never understood why GM would put the pcms under the hood instead of inside the vehicle.

 

[Blackie]

Pretty expensive, but at least it got figured out. Strange, the pcm went bad on the pcm in my old 01 work van. It actually was the same condition--it would start fine all during the work week, but if it sat over the weekend it wouldn't start. Did your old pcm have corrosion on the wires? I never understood why GM would put the pcms under the hood instead of inside the vehicle.

I didn't get to see the old one as they kept it for the core and I didn't think to look at it before I took it to the dealer for repairs.