HELP! Coil Craziness... VH45/VH41

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nismoneal87
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Joined: Tue Dec 27, 2016 4:20 pm
Car: 1995 240sx w/KA, 1995 240sx w/VH45, 2001 Frontier crewcab, 1981 corvette 4-spd

HELP! Coil Craziness... VH45/VH41

Postby nismoneal87 » Tue Dec 27, 2016 5:03 pm

Hello all.... my most recent project has been a VH45de powered s-14...

As is common with S-chassis, i got it with some issues....

Previous owner swore it had wiring issues, however replacing the ECU, after checking EVERY wire actually brought it back to life... So, while running it still has misfire issues, as 2,4,6,8, the WHOLE passenger side set of coils has the plastic casings melted.... (not uncommon to melt casing if ignition is left powered up for days on end, without collapsing the coils)...

SO i need coils... my engine comes from a 1995 Q45, and with one trip to ebay, its shocking how expensive the "correct" coils are... often listed for over $100 each.... however, a full set of 8 for a 97+ is less than $80......

Has anyone tried using the "4.1vh" coils in a 4.5?

they seem to be wired the same, share the same connector, visually all 8 look like the "1/2" coils for the 4.5 (stubby design to allow connector to clear) the only possible differences, that im unsure about, are the actual length of the spark plug lead, and im curious how easily "bolted in" they are......

There IS a years old thread on here about a guy using VW coils, and a spacer plate to raise the spark plug tube height to work with the VW coils... However the coils listed, are 4-wire, vs the stock 3-wire... he goes on to claim he has a sub-harness to bypass the ignitor.... but the thread is 3 years old, and cold... AND hes asking over $400 for a DIY kit...

acoording to EBAY at 12/27/16
8 ford v8 coils are $40 a set
8 Bmw/mercedes coils are $80 a set
8 1997 Q45 coils are $60 a set...
1 single 1995 Q45 coil is $125........ uh excuse me?

Maybe im just being cheap, but a ignition coil isnt rocket science... and the price difference is tangible... What are you guys running on your VH's?

:gotme


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centralcoaster33
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Re: HELP! Coil Craziness... VH45/VH41

Postby centralcoaster33 » Wed Dec 28, 2016 6:20 pm

Hi and welcome to NICO Club!

Yeah, I agree, you're just being cheap. I wouldn't cut that corner to save $$ and I'm a 240 guy (I'm cheap to!).

I looked around and found that guys kit for $400 at Performance VH. I guess you could contact him via his web page and ask about it. Looks like he's a member at this forum as well... maybe. Here's another thread that has similar photographs:
1990-1996-infiniti-q45-vh45de-ignition- ... 80117.html Ah, now I see, this must be the thread you've already found.

For me, I'd go to the junk yards. If that didn't work, I'd suck it up and pay full price for the correct ones if I had to. At that price, I'd only replace the bad ones, not buy a set.

If you learn anything more or decide to experiment, please, share with us. We'd like to know.

nismoneal87
Posts: 3
Joined: Tue Dec 27, 2016 4:20 pm
Car: 1995 240sx w/KA, 1995 240sx w/VH45, 2001 Frontier crewcab, 1981 corvette 4-spd

Re: HELP! Coil Craziness... VH45/VH41

Postby nismoneal87 » Fri Jan 13, 2017 12:31 pm

Well, now that the holidays have passed, I'm back to getting this turd buttoned up.

Today I ordered the coils for the 4.1 VH, as the entire set is half of the cost of a single coil for the 4.5

I'll post my findings/complications once they arrive, and i get a chance to actually fit them to the engine...

(CentralCoaster33- I appreciate you taking a peek, and I admit im being frugal... coils/connectors/seals arent as "fun" as body bits wheels and tires... and the cost of the correct set, new exceeds what i have in the car... haha so ill take a $100 gamble to save $1200... may work, may not....

however sometimes good things can come of rummaging through the parts bin.... I once had an SR that was bad about rear mains leaking... and ruining clutches... isis and other brands seemed insuffecient, never lasted, had to be ordered, and were pricy... I then discovered that the rear main from a VG v6 interchanges... $4 and got a Felpro seal locally same day...never leaked again... i was hoping i wasnt the first to try this coil swap, but ill be guinea pig... )

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centralcoaster33
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Re: HELP! Coil Craziness... VH45/VH41

Postby centralcoaster33 » Fri Jan 13, 2017 2:23 pm

Wow, cool cross referencing that main seal! Thanks in advance for your follow ups. If these work out, you'll have saved money for yourself and other owners as well. Here's to a great fit! :toast:

nismoneal87
Posts: 3
Joined: Tue Dec 27, 2016 4:20 pm
Car: 1995 240sx w/KA, 1995 240sx w/VH45, 2001 Frontier crewcab, 1981 corvette 4-spd

Re: HELP! Coil Craziness... VH45/VH41

Postby nismoneal87 » Fri Jan 27, 2017 8:49 pm

Ok, so my pile of garbage is closer... haha

I've still got a mountain of issues, before I can offer any real-world driving review, but YES... The inexpensive later-year model type coils plug directly into the harness, and seem to function perfectly. The only changes I've noted so far are:

1)Newer type coils fit best 15-20 degrees "twisted"... they do not line up with the bolt holes in the valve cover, rather simply "pop" onto the top of the spark plug, once allowed a small amount of rotation... I intend to either fabricate some brackets to use exsisting holes, or lazily use the cover to secure them down.

2)The '95 VH coil sub-harness has a single ground lead typically attached to the lead-most coil on each bank, where it physically bolts to the valve-cover, through the coil itself. I simply attached this to the valve-cover, as the OEM metal bracket is not present on the updated coils. This fired the engine, and worked for short drives... However I'm concerned about feedback to ECU or "noise" in the electrics so I do intend to ground all 8 coils.

3) The "lead" coils. Front on each bank. The ones advertised individually, the only ones to get a ground wire.... The reason, I think, this example isn't offered as a set? The ONLY differences I can detect, are a slightly different profile compared to the original coils (Narrower, similar to the updated coils) They also have an odd colored connector compared to the rest of each respective bank. The new coils plug straight into all aft SIX cylinders... The foremost cylinders, (1/2) that use the "brownish" connector have the side female lateral slots of the connector a fraction of a degree higher, than the rest of the ignition system. The difference is so slight, that by trimming the side "male" lateral alignment plastic on the two new coils with a mere set of snips on their respective leading edge, they plugged right in. and all fit beautifully... The whole set easily clears factory coil covers.


Can you point me towards some Injector knowledge? I'm curious if there's any VH/VG/SR/KA cross-overs...

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centralcoaster33
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Re: HELP! Coil Craziness... VH45/VH41

Postby centralcoaster33 » Mon Jan 30, 2017 1:20 pm

Cool stuff about the coils. I think pictures of the notches and rotations would be useful for this thread. Maybe some part numbers as well.

As far as injectors go, I know nothing and hope someone else chimes in. If you don't get any feedback for a while, you might want to create a new thread focused on that particular topic. Either by vehicle or by engine I suppose. Whichever seems to have more recent activity.


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