I've read that an inductive timing light can be used when troubleshooting coil packs. Where does the inductive clamp go on the coil pack?

 

You would need a spark plug wire inserted into the coil wire and on the sparkplug. An inductive pickup for a GM HIE distributor might work, placed directly over the coil.

 

So I would have to use a spark plug wire between the plug and the coil pack to extend the coil pack connection to the plug in order for the inductive clamp to clamp on. Can't I clamp onto one of the wires going to the coil pack connector?

 

No. The timing light need to be on the high voltage secondary side of the coil.

 

B.S. it works....I've been doing it think that since 2000!!!!

 

Clamp around the wire harness @ the coilpack!

 

For those of you that have had your car dyno'd the shops do the samething.....

 

Verified that my coil packs are good by using the timing light method, scanned for codes and there are none and replaced all of the spark plugs. Dumped a can of Sea Foam gas additive in my almost empty tank and filled up with premium. Car starts and runs fine. However, it seems like once it warms up, I hear the intermittent "putt - putt" from the exhaust pipe when it idles?? Any ideas??

 

If you want to test a possibly faulty coilpack, then you need to check and see if you're getting spark out of it. not that you're sending a signal into it.
typically, if the coilpack is good, it will draw enough current through the input lines that it will still cause the timing light to fire.
however, if the coilpack's secondary circuits are bad, it's possible that the input side of the coilpack will still draw enough current to set off the timing light but not actually give a spark output.

If all you're trying to do is get a signal to test timing or get an RPM reading for a dyno, then sure.. clamp on anywhere there's a wire going to a coilpack and you can find an RPM reference signal. but if you're trying to actually test the coilpacks, you need to verify input and output signals. can't do that by just connecting to the input.


Jobell, as for the putt-putt sound, "they all do that". Every Nissan I've owned for the last 15 years has done it.. And that's 8 of them with various engines: KA, VG, VE, VQ, SR.. I would suspect it has something to do with the ECU adjusting engine timing or idle mix to reduce emissions as much as possible in closed loop mode. they hardly did it when cold, but idled pretty poor when warm on stock ECU. After installing standalone on one of my KAs and a JWT ECU on my VE, the idle got better.

 

Matt,
Thanks for the reply. I didn't clamp the timing light around the coil pack wire connector. I actually bought a 16" spark plug wire with straight ends, removed one spark plug boot, attached a small bolt to that end so the bolt head would contact the spring in the coil pack. Inserted the end with the bolt into the coil pack ensuring that the bolt head made contact with the spring in the coil pack, attached the other end of the spark plug wire to the spark plug. Clamped around the spark plug wire, started the car and watched the timing light. Coil packs didn't skip a beat. Was that a good test of the coil packs??

Joe

 

have you checked for exhaust leaks? my max is putting a little at start-up, and sometimes i feel a loss of power when stepping on it.

 

IF it misses it still interrupts the signal I pickup thru the harness......Been doing since 2000 on many Maxima not just my own....but I have used the Lisle ignition spark tester tool that hooks to the coilpack output side and the spark plug.....Kinda hard to get a good crisp connection in really deep spark plug tubes though....

 

I am in EXACTLY the same boat with my 98 I30. Car runs fine until it gets warm. Noticed a putt putt in the exhaust and can't figure out which coil is bad. I buy used OEM, but thats also risky because they can be bad as well. No check engine light. OBDII reader never finds any stored codes. Wow, the semi failing state of a coil is frustrating.

I saw one thread where this guy viewed the output of ignition coils on an oscilloscope. It is definitive. And yeah, that was easy....NOT!

I am getting to the point where I just replace all 6 coils with new OEM.

 

On the way home tonight, I noticed that the car still doesn't idle correctly. When stopped at a red light and if I let up on the brakes a bit, the car will jerk forward. RPMs are 400 stopped in drive and 600 in neutral. Sometimes the idle goes down and the car sounds like it will stall. The car doesn't idle smooth like it did; now it's rough. Does the IAC have anything to do with this??

 

Maybe, maybe not. I've got a 1995 (339000km) and a 1997 Maxima QX (260000km), both VQ20DE variants. My '95 model does just as you describe on warm idle (the '97 idles flawlessly). Tried a few different things, including swapping IACV, cleaning the IACV, and buying a used one from the same model year. Nothing has worked so far, but the acceleration and just about everything else technically is fine.

Adding TC-W3 on each fill-up does smooth it out a bit, though (quieter), see this thread:

http://www.ls1.com/forums/f48/been-testing-91206/

 

My car is possessed!!! It started running fine on Wednesday. Didn't drive it yesterday and today it was still running fine. So I decided to clean the throttle body and try to increase the idle speed. The Haynes book states to disconnect the TPS before adjusting the idle speed. When I did that, the car died. That phillips head screw up by the throttle body didn't do anything. So I cleaned my throttle body and MAF sensor, now the cars idles rough, go figure. I even replaced the original PCV valve; no help.