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Discussion Starter #1
Back in 2003, my 96 6.5 was having an intermittent stalling/no start problem. Truck would either die while driving then not want to re-start or would just not start - it would crank over but not run. A peculiar symptom associated was that I would get lose dash warning/idiot lights upon stall or when truck would not want to start.

I found that if I slammed the steering wheel up & down through the full tilt range, sometimes the dash would light back up and the truck would start & run. Was told by someone over on The Diesel Page when I was a member there that I needed to replace a part of the ignition switch assembly, a p/n 26036311 and that should fix the problem. Got the part from my local Chevy dealer and had it installed and the problem was fixed.

Fast forward to 2007

Truck is once again randomly dieing with associated loss of dash indicator lights and refusal to re-start. This time, jarring the steering wheel column seems to do no good and the truck will only randomly start if the key is turned on and off or I leave it sit. Indicator lights will sometimes sit there and flicker faintly at times.

Does it sound like I need to replace the actual ignition switch or ? The part I replaced before is listed as on GMPartsDirect.com as the Ignition Buzzer Switch whereas AC Delco lists it as p/n D1481C, Ignition Starter Switch. I've read here on the boards that the Chevrolet design for this part sucks - could this same part be failing again after 4 years?

I really need to pin this down and fix the problem as losing power while driving in rush hour traffic on the freeway or towing my boat is not good as losing power steering and most of my braking power in these situations could lead to a very bad situation.
 

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Suspect the FSD\PMD this time, but go thru your wiring harnesses and battery cables for connectivity - oxidation \corrosion, loose, etc - the battery posts, the main harness grounds at the passenger-side rear intake manifold stud.

If you got aftermarket, may be the ign switch, but check the other electrical stuff first.
 

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Discussion Starter #3 (Edited)
Besides the manifold ground, are there others i should check? On the battery cables, how can you tell if they have internal corrosion? I've done the recommended battery post mods and will pull everything apart & re-clean with baking soda.

I've got Bill Heath's Super FSD setup so I'm covered if that turns out to be bad - would a failing FSD cause me to loose my dash warning lights though?
 

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quote"
Truck is once again randomly dieing with associated loss of dash indicator lights and refusal to re-start."quote


I would put my money on the ignition switch again, I don't think the PMD/FSD controls the dash indicator lights.
 

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That's one of the benefits of keeping your sig up to date, folks - any mention of location of FSD\PMD, or battery-post upgrades, or any info pertinent to diagnosis\troubleshooting.

Don't suspect the FSD\PMD at this time - got your ground in the correct position?

But do do the wiring\grounds checkout - move the harnesses around, in position, try to force the intermittent connection.

If you winter-ize the electrics and the symptom still occurs, suspect the switch.

But, that would be a first, in my experience - you indicated getting the switch from GM, but, as the aftermarket copies are flimsy versions of oem, they would be suspect in a case like this.
 

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gmctd;1607451; said:
That's one of the benefits of keeping your sig up to date, folks - any mention of location of FSD\PMD, or battery-post upgrades, or any info pertinent to diagnosis\troubleshooting.

Don't suspect the FSD\PMD at this time - got your ground in the correct position?

But do do the wiring\grounds checkout - move the harnesses around, in position, try to force the intermittent connection.

If you winter-ize the electrics and the symptom still occurs, suspect the switch.

But, that would be a first, in my experience - you indicated getting the switch from GM, but, as the aftermarket copies are flimsy versions of oem, they would be suspect in a case like this.
Are Sorensen switches any good? Are they aftermarket?
 

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Best thing in any case is compare what you get with what you pull out - for switches, oem contacts are larger, the plastic is thicker, the metal bracketry is heavier.

The switch is a known trouble spot, so the cheaper stuff won't give even oem service, there.

Would be even worse if switching a bunch of electrical add-ons, but first thing to suspect is the vehicle wiring, as that is well known for annual gremlin infestation.
 

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There's a simple test to see if it's the ignition switch. Check for power at the ecm fuses with the key "on". If you've got power, then the switch is good and you can save the $200. As gmctd said, check the ground at the pass. side rear manifold studs. This is where the pcm grounds to the motor. Also check the ground connection from motor to battery. You need to pay close attentino to the passenger side ground cable as well as the body ground.

I've had same symptoms that you describe. One time it was a bad PCM. The other time it was a bad ground for the pcm (rear manifold stud on pass side). It was very difficult to diagnose when I had the bad pcm because there was no ryme or reason as to when it would stall.

When the truck is running, wiggle the ground wires and see if you can cause the engine to stumble or stall.

Good luck with it. Electrical gremlins are a test of patience.
 

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Discussion Starter #9
gmctd;1607451; said:
you indicated getting the switch from GM, but, as the aftermarket copies are flimsy versions of oem, they would be suspect in a case like this.
I thought Delco made the electrical parts for Chevrolet? Is AC Delco not the same as the part you would buy from a Chevy dealer?
 

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Yes, oem DELCO or DELPHI would be correct replacement, but would be hard to imagine that a new oem replacement would crater within several years.

That is why I suggested looking elsewhere - your symptoms are not identical, where it will only crank after sitting awhile.

Batteries, connections, even a bad starter would seem more like it, now, but winter-time usually brings on wiring problems, starting with oxidized\corroded battery connections, etc.

I'd try that stuff, first.
 

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Discussion Starter #11
I'll check out the grounds, battery connections, etc. tomorrow now that we're getting a break from 3 days of rain. If it is that ignition switch again, I'm still unclear if AC Delco is the same part I would buy from the dealer? I can get the AC Delco p/n D1481C online for $115 whereas GM list for the equivalent p/n 26036311 is $215 or $114 at GMpartsdirect.com.

One thing I forgot to mention is that sometimes it will lose the dash lights & die as I shift the transmission from Park going into gear. Don't know if that means anything but thought I'd throw it out as related.
 

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Same part, different vendor - I'd make sure the other stuff was functional B4 spending 115bucks on a 'nuther switch.
 

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grab the wire cluster under the dash and wiggle it around. see if you can reproduce the problem.
 

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Discussion Starter #14 (Edited)
As joispoi suggested, I checked for power at the ECM fuse locations in the underhood fuse box. When truck wont start with loss of dash lights, I am getting power to ECM-B but no power to ECM-I - when truck will start, I get power to both ECM locations.

I also found that by beating on the underside of the steering column with my fist, I can get the dash lights to come back on & truck to start - sometimes.

I'm going to check the grounds over but it is sure looking to me like that ignition switch part again. If the cause was a bad ground at the PCM, engine, or battery, I can't see how beating on the steering column would cause one of the grounds in the engine compartment to let loose or re-connect.
 

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If it helps you, when my ignition module went to crap, my fuel gauge would peg out at max when my truck stalled. Sometimes I could drive for days, other times it wouldn't start. I finally had it towed to a garage I use work at when my wife was in labor and I couldn't limp it home like I would always due. Difference for me between ignition module and PMD failure was gas gauge pegged out max when stall. PMD failure probs I had didn't due that. Unfortunately ignition module isn't cheap for these trucks.



Fishnfool;1606730; said:
Back in 2003, my 96 6.5 was having an intermittent stalling/no start problem. Truck would either die while driving then not want to re-start or would just not start - it would crank over but not run. A peculiar symptom associated was that I would get lose dash warning/idiot lights upon stall or when truck would not want to start.

I found that if I slammed the steering wheel up & down through the full tilt range, sometimes the dash would light back up and the truck would start & run. Was told by someone over on The Diesel Page when I was a member there that I needed to replace a part of the ignition switch assembly, a p/n 26036311 and that should fix the problem. Got the part from my local Chevy dealer and had it installed and the problem was fixed.

Fast forward to 2007

Truck is once again randomly dieing with associated loss of dash indicator lights and refusal to re-start. This time, jarring the steering wheel column seems to do no good and the truck will only randomly start if the key is turned on and off or I leave it sit. Indicator lights will sometimes sit there and flicker faintly at times.

Does it sound like I need to replace the actual ignition switch or ? The part I replaced before is listed as on GMPartsDirect.com as the Ignition Buzzer Switch whereas AC Delco lists it as p/n D1481C, Ignition Starter Switch. I've read here on the boards that the Chevrolet design for this part sucks - could this same part be failing again after 4 years?

I really need to pin this down and fix the problem as losing power while driving in rush hour traffic on the freeway or towing my boat is not good as losing power steering and most of my braking power in these situations could lead to a very bad situation.
 

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Troubleshooting is the process of eliminating all the good stuff - what's left is the bad stuff.

If you're satisfied the Ign switch has failed again, replacing it would be the next step.
 

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Discussion Starter #17
No, I'm not certain it's the switch again but wiggling wire harness's, connectors, etc, does nothing to indicate a cause whereas direct shock to the area housing the previously replaced part does.

Would really like to know what the significance of losing power at the ECM-I fuse means and if it could be directly related to the ignition wiring and my problem. If the design of this electrical part is so weak then I would think more people would be experiencing this same problem and therefore easier to diagnose.
 

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ECMB is hot anytime the battery cables are connected to the batteries - the other fuse is hot thru the Ign switch in Run and Start.

Faulty wiring and connections can cause the same symptom - checking the other stuff is free, and if it all proves out, then the 115 dollar switch will heal the symptom.

And, vice versa
 

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Discussion Starter #19
A.C. must stand for All Crap

After checking all my grounds, battery connections, fuses, etc, the problem turned out to be the ignition switch going bad AGAIN after only 4 years. Have put over 500 miles on truck since replacing the switch and have not had a single hiccup. I tore the old switch apart and three of the contact levers had moderate pitting/oxidation - apparently enough to cause my stalling/starting problem.

I ordered the AC Delco D1481C Ignition Switch from www.oehq.com for $114.46 with no tax and free shipping which was a savings of over $100 from what my local Chevy Stealer was asking.

Thanks Chevrolet & AC Delco for yet another defectively designed component requiring replacement way too often :thumbsdow
 

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Good fix - any chance you can post pics of the switch configuration and internal damage?

Could give others a better idea of failure mode and method.
 
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