Jump to content

Dielectric grease applied to both ends of ingition wires -- now rough idle and stalls

dukbludvl
 Share

Recommended Posts

dukbludvl Enthusiast

dukbludvl

Posted
Posted

So, I'm a moron. It's been years since I've changed plugs and wires. This week, I installed new Delco platinum plugs and new Delco wires on my 2003 GMC Yukon 5.3L 2wd with Delphi coils, about 150k on the motor. Everything went well with getting the old plugs out and new plugs in. Then, I went ahead and installed the new ignition wires and mindlessly glopped a bunch of dielectric grease on BOTH ends of the ignition wires before putting them on, thinking it would help with conduction and not act as an insulator, as it obviously does.

I should have known right away that I effed that up because I figured I'd fire up the engine and she'd be smooth and happy. But, it was actually a little hard to start then it wanted to stall. I drove it around some -- ran in to work and back to the house, so maybe 30 miles round trip, with a couple stops in the middle. It idled rough, but otherwise ran fine most of the time -- no ticks, knocks, bangs, and seemingly no misfires, but maybe I missed some misfires? It did stall on me a few times when I started it and tried to put it in reverse to get out of a parking space.

Anyway -- need your advice. How do I undo this mix-up? My plan is this:

A. Remove these wires with all the grease in them and put on a totally new set of wires with only a thin coating of grease applied with a Q-tip to the boot only -- and not to the conductive metal/wire ends inside the boot.

B. Wipe the grease off the plug terminals that the boots were installed over as best I can with a paper towel.

C. Take a Q-tip and try to wipe the grease off the inside of the coil boots/connectors, and wipe the outsides of the coils with paper towels to try to get all the grease off as best I can.

My questions are these:

1. Any other suggestions about how to get the grease off the plugs so it won't interfere with the conductivity of the plugs? Is wiping it off sufficient, or should I replace my new plugs with another set of new plugs?

2. Have I permanently damaged the Delphi coils by essentially cramming grease up them from pushing the wires on? Do I need to replace my coils?

3. Anything else you all recommend?

Thanks in advance for your help on this. I just want to get my Yukon back running right again. The stalls and rough idle had me freaked out for a bit.

Jon

  • Like 1
CamGTP Senior Enthusiast

CamGTP

Posted
Posted

Just wipe all the grease off/out and slap it back together, it should be just fine.

 

The electrical grease won't damage anything like the wires or coils.

Mike GMC Enthusiast

Mike GMC

Posted
Posted

I always put some dielectric grease on both ends.  Double check that they are fully "clicked" on and fully seated.  If that doesn't work, ohm the wires.  New doesn't always mean good.  Did you gap the plugs or just trust that they were correct out of the box?

  • Like 1
CamGTP Senior Enthusiast

CamGTP

Posted
Posted

The only real way the gap would be a concern is if they were like .080 or something.

 

They run fine on .025 and .060. People who run boost run lower gaps for spark blow out but you may notice spark blow out at high rpm's with .060.

SierrraLC9 Enthusiast

SierrraLC9

Posted
Posted

The grease shouldnt cause an issue and will help seal and lubricate the boot. Make sure you didn't leave a vacuum line or breather tube loose. 

Mike GMC Enthusiast

Mike GMC

Posted
Posted
13 hours ago, CamGTP said:

The only real way the gap would be a concern is if they were like .080 or something.

 

They run fine on .025 and .060. People who run boost run lower gaps for spark blow out but you may notice spark blow out at high rpm's with .060.

Very true.  But I have seen rough idle when the gaps are different from plug to plug.  They all work, but they all work a little differently.  As long as the are all basically the same, I agree, anything in the range you mention works.

dukbludvl Enthusiast

dukbludvl

Posted
  • Author
Posted

I didn't check the gaps with a tool, but I eyeballed them and they all looked the same coming out of the box.  I'm starting to think I don't really have any issues with the plugs/wires, and that maybe this is more of an air/fuel mixture or air delivery issue.  I drove it about 30 miles tonight with a few stops/starts and had no issues with idle or stalling.  In fact, I think maybe the idle is better now than it was before the plug/wire change.  It's steady at 650, whereas before it was usually around 500 but a little bouncy and sometimes dipped below 500.  I just got this Yukon a month ago from the only other owner who got it new in 2003 and had it for 17 years.  He installed a K&N cold air intake years ago, and the K&N filter is quite dirty.  So, there's that, plus I think maybe my rough idle and stalling could have been due to a sticking throttle body.  My old 2000 Yukon did that for the first time in 2002 and it freaked me out.  That 2000 Yukon had drive by cable, so I just moved the butterfly plate in the TB and cleaned all around it good and it was good fro the next 100k miles or more.  This 2003 is drive by wire, so I think I need to find a buddy to get on the accelerator pedal to open up the butterfly plate while I clean around it -- is that right?  My plan is also to reinstall the stock air filter box and get rid of the cold air intake.  I'll clean up the TB when I do that hopefully this weekend.

 

Now, for a perhaps related issue -- or maybe it's a totally separate issue.  I had a CEL code on last week before I did the plugs/wires, and I had it read and it came back as P0420, Catalyst System Efficiency Below Threshold (Bank 1).  The CEL stayed on for a day, then went off for a day -- did that most of last week.  Now, after the plugs/wires change, the CEL has been on steady, so I just had it read again at AutoZone tonight.  It's showing the following:

 

P0420 Catalyst System Efficiency Below Threshold (Bank 1)

P0101 Mass or Volume Air Flow Circuit Range/Performance

P0102 Mass or Volume Air Flow Circuit Low Input

P0101 Mass or Volume Air Flow Circuit Range/Performance

 

Not sure why the same P0101 code is on there twice.  Anyway, the AutoZone print out say "ASE certified Master Technicians have seen this issue on your type of vehicle and the most like solution is:  Repair Engine Control Module (ECM) Wiring.

 

Anybody have any insights into what might be going on with this?

stevejones Enthusiast

stevejones

Posted
Posted

You really want to be viewing the data stream to accurately diagnose your DTCs.  In lieu of that; we'll load up the internet parts cannon & fire:  your cats are shot (P0420) and you need a new MAF (P0101/2).

 

Good luck!

SierrraLC9 Enthusiast

SierrraLC9

Posted
Posted

If your K&N filter is an oiled filter you likely need to clean your MAF. I would do this first and see if where it takes you.  

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing

  • Latest Articles

  • Posts

    • Atlas
      2027 GMC Sierra: Official Discussion

      By Atlas · Posted

      Yes, you must have seen my thread on the Blazer. HOT GARBAGE, but I love them anyway. I'm convinced every car guy has a soft sport for an S/T series somewheres. Probably even a Panther too, if I'm being an honest car guy. That doesn't mean they aren't junk. And they definitely don't get better with age. I sometimes play with old cars, but that's by choice. I don't rely on them and they aren't my everyday fleet.   Derek plays the common man on Youtube and that's no doubt where he started. Now he has Youtube money (and Motortrend, etc). You think his crews and his wife ride around in old beaters when they're chasing him and his wrecks across the country? No he's got newer and nicer stuff for that, you'll see glimpses of it in the footage.
    • Atlas
      2027 GMC Sierra: Official Discussion

      By Atlas · Posted

      You refuse to own anything made in this century yet you reportedly own... a 2007 Silverado, which is now almost 20 years old. The dissonance.... turn up your hearing aid?   You clearly don't understand the government contracting process, brother. We send people to die on front lines, keep the public safe, and make people's husbands, wives, children enter burning buildings with equipment from .....wait for it.....   ...the lowest bidder....   Just because something is used for a long time doesn't mean it's good. But it might be cheap and plentiful.   Please, continue to whine about new trucks in a thread dedicated to new trucks, which you've said you'll never own. We get it. Go tell everyone how you're stuck in time on a Panther forum. I mean, Jesus, an 86 isn't even one of the good Panthers.
    • KARNUT
      2027 GMC Sierra: Official Discussion

      By KARNUT · Posted

      It really is comical when people don’t agree or see the reason some people prefer the older vehicles. They become condescending. All the while they may be busting their knuckles on old vehicles. I have found memories of swapping out engines in my old GM cars in a weekend without much hassle. Unlike today. One wrong move a computer will shut you down. Even on something as easy as a brake job. There’s a pretty comical YouTuber called the car wizard. A garage owner who puts it all in perspective. Another Vicegrip garage that’s shows just how tough the old stuff is. 
    • Jsdirt
      2027 GMC Sierra: Official Discussion

      By Jsdirt · Posted

      I was around and remember that era very well, so I'm calling b/s on that statement. If they were that bad no police department or taxi company would've bought a single one ... but they were used in both services (and fire) for DECADES. They were bulletproof and proven. Even the early 21st century ones weren't too bad! The early models were legendary.   Mine is proof, but people like atlas are blinded by agenda and refuse to believe facts right before their very eyes.   Even decades after they were built, a new generation started driving them, posting all their builds and shenanigans on Grandmarq.net and Crownvic.net. The failures would show up then, since they all were deep past 100k-150k miles by that point, and younger drivers tend to be a little aggressive, especially with vehicles than can lay a one-tire fire for as long as you hold your foot in it. They've more than proven themselves over the decades.   The only thing that'll really take them out is road salt. The bodies and sheet metal were garbage. A victim of the cheapout FoMoCo and GM have been partaking in before then, and since.   Today it's the stuff that counts - the undercarriage that rots away first!    GMs Caprice was no slouch either. Reliable as a stone ax - the opposite of what they build now.    
    • Jsdirt
      2027 GMC Sierra: Official Discussion

      By Jsdirt · Posted

      Let me know how your vehicles do in 10 years. You don't know ******, kid. 😂    There's a reason that Panther platform was used as police, fire, and taxi service for DECADES ... long before you were born, apparently.

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...