Haha, you got me on the terminology, we talk different in the south. Also, I got out of the wrenching business a few years ago because this area is not exactly wealthy. The cost of tools/equipment vs income just wasn't worth it for what I enjoyed doing.

Anyway, since I've tuned the car and have heard horror stories about bad tunes (mine are Jon Lund) I was concerned about the tune advancing the timing too far but I watched my knock retard and it shows 0 while driving and under moderate acceleration. However, it reads -4 during WOT. As I understand it, this is backwards of what you would think and is actually advancing the timing by 4 degrees. Can anybody confirm this? I also understand the copperhead computer has the capability to advance timing until it detects spark knock/predetontation/detonation/whatever. If it does have that capability, wouldn't the aftermarket tune affect that or completely take it away? I would imagine the flash of spark knock your talking about the coyotes have a tendency for is because of the high compression?

 

Well this is not a dialect or linguistic variance, it's an error that perpetuates misunderstanding about how engines work so, stop using the term, please.

Your Lund tunes are among the best so, you have little to be concerned about. The coyote can add timing or pull it back, based on real time closed loop feedback from the rather hyper knock sensors on the engine. Added timing will show as a negative kr value.

 

Very light pinging used to be referred to as pre-ignition and the term was used by GM, Ford, and Chrysler as well as many others. I trained 2 years at a technical college, 1 year at Scranton College, 9 months at the GM Training center, and worked in the field as a diagnostician and spent about 2 years as a dealership line technician over 35 years ago albeit.

The term Pre-ignition is still used quite regularly by many. It IS actually detonation, but it's usually light, and MUCH less destructive in the short term, as compared to hard knocking detonations which can destroy your engine on first occurrence at times. The persistent rattling during accelerations is a bad thing if this is occurring as a result of any level of detonations. You need to get to the bottom of this in short order.

Put it all back stock and see if it stops. If yes, move forward from there.

The term Pre-detonation is totally inaccurate... It either did or did not detonate.
Pre-ignition IS detonation.

I'm sure that 5LHO will probably disagree with me, but this is my opinion.

Keep us posted.

 

this car has knock sensors, and because of that any knock will result in a timing retard, and the noise would stop. so it is very safe to say that what he is experiencing is not knock/detonation/pre-ignition, whatever you decide you like to call it. there is absolutely no reason to return to stock to see if that takes care of it, unless you like wasting your time.

 

Returning to stock isn't specifically or only related to the detonation subject.

Returning to stock can eliminate or confirm whether the noise is related to his new CAI. Not debating on how well it pulls timing, we're all aware of that. Peace of mind is seldom a waste of time.

 

Why would I disagree, this is what I've been trying to get across all along.

I teach auto shop but I've been out of the classroom for a couple years. Maybe I'm a little rusty on the communication skills.

 

It's been a long week of medical treatment and meds, perhaps I misread something. Blow it off...

 

Here's a document I used as a reference in the classroom for a long time to explain the differences. Allen Cline wrote lots of articles and books on automotive technical matters.

http://www.contactmagazine.com/Issue...ineBasics.html

Take care and get well!