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Intermittent hard starting

Cygnus X-1

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Jul 25, 2018
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Saw you mentioned this again in your lifter tap thread and that you still haven’t tried cleaning up the main grounding points yet.

At least try cleaning up the chassis grounding point on the passenger side strut tower. Check resistance with a multimeter in ohms before and after. Ignition coils rely heavily on this grounding point.

You could also add a helper cable to piggyback on the OEM grounding wire between the engine block and chassis. I had extra 8ga cables laying around from a ground wiring kit for a different vehicle.

Electrical resistance on the passenger side was ~11 ohms and ~6 ohms on the driver side. After a helper cable was added on each side, electrical resistance for both were down to 0.6 ohms.

I’ve since cleaned up the passenger side grounding point and brought it down to 0.4 ohms. Also cleaned up the transmission chassis grounding point (since I had the airbox out) and got it down to 0.2 ohms. Still haven’t cleaned up the 3 grounding points on the driver side strut tower since the ECM has to come out. Goal is to get electrical resistance down to 0.1 ohms. I’ve also checked various bolts on the engine block and getting 0.2-0.3 ohms.
 

Y0UKN0WITSCHRIS

Well-Known Member
Mar 6, 2018
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Saw you mentioned this again in your lifter tap thread and that you still haven’t tried cleaning up the main grounding points yet.

At least try cleaning up the chassis grounding point on the passenger side strut tower. Check resistance with a multimeter in ohms before and after. Ignition coils rely heavily on this grounding point.

You could also add a helper cable to piggyback on the OEM grounding wire between the engine block and chassis. I had extra 8ga cables laying around from a ground wiring kit for a different vehicle.

Electrical resistance on the passenger side was ~11 ohms and ~6 ohms on the driver side. After a helper cable was added on each side, electrical resistance for both were down to 0.6 ohms.

I’ve since cleaned up the passenger side grounding point and brought it down to 0.4 ohms. Also cleaned up the transmission chassis grounding point (since I had the airbox out) and got it down to 0.2 ohms. Still haven’t cleaned up the 3 grounding points on the driver side strut tower since the ECM has to come out. Goal is to get electrical resistance down to 0.1 ohms. I’ve also checked various bolts on the engine block and getting 0.2-0.3 ohms.
Saw you mentioned this again in your lifter tap thread and that you still haven’t tried cleaning up the main grounding points yet.

At least try cleaning up the chassis grounding point on the passenger side strut tower. Check resistance with a multimeter in ohms before and after. Ignition coils rely heavily on this grounding point.

You could also add a helper cable to piggyback on the OEM grounding wire between the engine block and chassis. I had extra 8ga cables laying around from a ground wiring kit for a different vehicle.

Electrical resistance on the passenger side was ~11 ohms and ~6 ohms on the driver side. After a helper cable was added on each side, electrical resistance for both were down to 0.6 ohms.

I’ve since cleaned up the passenger side grounding point and brought it down to 0.4 ohms. Also cleaned up the transmission chassis grounding point (since I had the airbox out) and got it down to 0.2 ohms. Still haven’t cleaned up the 3 grounding points on the driver side strut tower since the ECM has to come out. Goal is to get electrical resistance down to 0.1 ohms. I’ve also checked various bolts on the engine block and getting 0.2-0.3 ohms.
Maybe you could make a thread(pics included) on doing this for some of the newbies. And produce a wiring kit for the N like you did for the VT. I had one on my VT and it was a pretty noticble difference.
 

Cygnus X-1

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Jul 25, 2018
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I’d like to see other individuals test their grounding points and try the simple cleaning method first before I consider the creation of a product.
 

801Burnsie

New Member
Apr 26, 2019
11
8
3
Utah
Ok I just experienced the hard start when leaving work last night sat for about 9 hours 550 miles on the car. just out of curiosity to find a common denominator I drive mine in N mode custom with engine in sport and exhaust in sport+ everything else in normal for daily driving. I don't change it back to normal drive mode before shutting it off. Is everyone that is experiencing this, driving their car and turning it off while in N mode. I just have a hard time believing that this is linked to voltage as the car cranks fine and fast its just hesitant to start... Kind of a stretch but, I almost feel like the car is trying to run off the settings you were last in but while in the normal drive mode making the car have a hard time starting as the settings will change idle for sure, air fuel ratio maybe, and exhaust breathability for sure... Thoughts?
 

Y0UKN0WITSCHRIS

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Mar 6, 2018
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Ok I just experienced the hard start when leaving work last night sat for about 9 hours 550 miles on the car. just out of curiosity to find a common denominator I drive mine in N mode custom with engine in sport and exhaust in sport+ everything else in normal for daily driving. I don't change it back to normal drive mode before shutting it off. Is everyone that is experiencing this, driving their car and turning it off while in N mode. I just have a hard time believing that this is linked to voltage as the car cranks fine and fast its just hesitant to start... Kind of a stretch but, I almost feel like the car is trying to run off the settings you were last in but while in the normal drive mode making the car have a hard time starting as the settings will change idle for sure, air fuel ratio maybe, and exhaust breathability for sure... Thoughts?
My N custom mode is everything maxed out but suspension in sport. When I drive to work in morning it’s in normal mode and I’ve experienced hard starts half of the time after work. Which is sitting for 9-12 hours at a time. However as mentioned before it’s done it with both cold and hard starts.
 

Y0UKN0WITSCHRIS

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Mar 6, 2018
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On a Side note now that the weather is nicer and my bike is getting substationally more drive time then the N it hasn’t hard started once for me. I’m now driving the N maybe 2-3x a week if that and everytime it’s started fine other than the tap.
 

801Burnsie

New Member
Apr 26, 2019
11
8
3
Utah
Ok so I've posted before about having the "unusual drawn out start" would usually happen in the morning and sometimes when I left work 10 hours later, then it started happening every morning.... Today it threw a cylinder 2 miss fire code that is ***clearly present around 3 grand while hooked up to the GDS*** she's at the dealership for the weekend. I will share our findings next week. And I don't really care to hear about grounds again thanks
 
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Y0UKN0WITSCHRIS

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Mar 6, 2018
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Ok so I've posted before about having the "unusual drawn out start" would usually happen in the morning and sometimes when I left work 10 hours later, then it started happening every morning.... Today it threw a cylinder 2 miss fire code that is ***clearly present around 3 grand while hooked up to the GDS*** she's at the dealership for the weekend. I will share our findings next week. And I don't really care to hear about grounds again thanks
Looking forward to what comes of this ! I drove my N 3x this week and everytime she was fighting me to start. However I haven’t played with the grounds yet.. I’ll get around to it eventually lol
 

Cygnus X-1

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Jul 25, 2018
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Air, fuel, spark. Amazing that some will not even do the most rudimentary thing, which is pull the spark plugs and check the gaps.

Respect the spark. Ignore the electrical system (including grounds) at your peril.
 

R Veloster N

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Mar 5, 2019
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Rocky Mountains, US
This is simple mechanics 101. I agree with Cygnus, it's a simple process, that saves you time effort and heartburn.

The sooner you get to know your car, the easier it is to diagnosis problems. Or you can take it back and forth to a tech that doesn't and really doesn't care.
 

801Burnsie

New Member
Apr 26, 2019
11
8
3
Utah
FYI... I work at the dealership @Cygnus X-1 I just didn't care to screw with it because if a plug was needed I didn't even have one yet so I ordered one for monday and took a sonata for the weekend. Appon inspection of the plug the gap was at .035 in. And all data shows between .0275 and .0314 before changing out the spark plug I swapped it with another cylinder and the miss followed replace plug and coil miss fire is no longer present. And for science I will be driving home with the GDS hooked up just to run live data for a little extra verification. But thanks for your smart ass input again @Cygnus X-1 this will be my last post here as a couple of toxic people (clears throat) make this a shitty and unwelcome place to post. ✌
 
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R Veloster N

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Mar 5, 2019
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One other thing, check the coil packs, for those who are still having issues. Pull them all, one at a time and make sure none of the spark plug receptacles are cracked and arcing on the head. You'll see a small telltale light gray or brown smudge on the spark plug receptacle, where it's arcing.
 
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Y0UKN0WITSCHRIS

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Here’s the results of me testing the two main grounds in the 5min I had this morning. First pic is shorting the leads out to test wire resistance. Second is engine ground strap onto passenger shock tower and third is battery ground to drivers shock tower.70D0918E-7840-4406-9927-31FF73A12360.jpegFF47D6BE-E25A-4ABC-AF24-AC80FBF879D9.jpegF1E5C1BE-51BC-4100-A47E-BDEAA6CF5442.jpeg
 
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R Veloster N

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Ideally a ground should be of zero ohms resistance. However, not all grounds will result in "0" ohms.

ohms.jpgOhm’s law states that, in an electrical circuit, the current passing through a conductor between two points is directly proportional to the potential difference (.i.e. voltage drop or voltage) across two points, and inversely proportional to the resistance between them.

Otherwise; Resistance determines how much current will flow through a component. A very high resistance allows a small amount of current to flow. A very low resistance allows a large amount of current to flow.
 
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Y0UKN0WITSCHRIS

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Mar 6, 2018
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Ideally a ground should be of zero ohms resistance. However, not all will grounds will result in "0" ohms.

View attachment 8321Ohm’s law states that, in an electrical circuit, the current passing through a conductor between two points is directly proportional to the potential difference (.i.e. voltage drop or voltage) across two points, and inversely proportional to the resistance between them.

Otherwise; Resistance determines how much current will flow through a component. A very high resistance allows a small amount of current to flow. A very low resistance allows a large amount of current to flow.
So dumbed down a bit my passenger side ground is okay but the battery one is higher than it should be ? Lol
 
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