Spark burn times?

[Surtr]

I've been having some starting / idling issues lately so I've been running a bunch of tests on my fuel injection and ignition system. Today I was looking at the spark kV and burn times and noticed that on cylinders 1,2 and 3 the burn times average about 2.35ms each. On 4,5 and 6 they all average around 1.3ms.

I'm thinking the difference between the first 3 and second 3 could be the plug under the throttle body that controls the fuel injection and tends to get all messed up. Any other ideas?

Does anybody know what the normal burn time and / or spark and power kV is for an '89 325i (w/ m20)?

[E30nate]

if i remember correctly, the general rule of thumb for kv is around 1.5. could be wrong though.

[Surtr]

The manual for the meter says it should be between 1 and 4 kV. Burn times should be between 1ms and 3ms. I'm in those ranges, except for some kV spikes on some of the cylinders.

Oddly after letting it sit for a while, then warming back up while I messed with it, the burn times started to be more stable. Now most of them are below 2ms, except two, which are around 2.5 or 2.6. I can't make up my mind about whether this is temperature dependent or not.

On a related note, am I the only person that has a hard time telling if these bavauto ignition cables are on correctly? It seems like the problem could be caused by them buzzing around and coming off the plugs.

[E30nate]

you can try putting di-electric grease in the boots if you havnt already. helps make a better contact.

[Surtr]

you can try putting di-electric grease in the boots if you havnt already. helps make a better contact.

You know, I used to always do that, but I don't think I have on this car. Thanks for the tip. I'm gonna be kinda pissed if that's what fixes it though :(. heh.

But erm...does it really make a better connection? I used to just put it on everything to keep out moisture and corrosion. Not really sure how non conductive grease could make a better connection. I'll do it anyway though.

[E30nate]

i dont know if it makes a better connection, i was always told it does though. it kinda makes sense. water is a conductor, so i guess the wetness of the grease could work as a conductor.

[Surtr]

I could be wrong, but I thought the whole point of dielectric grease was that it is non-conductive.

I think the biggest problem with the cables is that they're too small to use with those things that come on spark plug terminals, but too big to make a good connection without them. I haven't seen many cars that have them, which kinda makes think they are shit. *searches to see if anybody else has complained*

[E30nate]

ive heard mixed things about the bav auto wires, but never used them. i got the hook up on oem stuff so thats what i use.

[Surtr]

By having a wholesale / resale account? I'm just curious because I couldn't find anybody who would give me a resale account that would make OEM prices even comparable to aftermarket stuff.

[E30nate]

my brother works at a shop and his boss gives him stuff at his cost.

[AndrewBird]

Dielectric grease is non-conductive, as is water (unless it has other substances in it).