Vktrsksmyntz

So in other words the J&S IS a steamy pile o' ****?
What do you mean by key on ignition off position?

IceY2K1Max

iTrader: (1)

I'm not sure what thread you're reading.

I've only heard of the coil problem on the eManage with both the Maxima and 350z. Many Maximas(VQ30 at least) are running the J&S without ANY problems.

Sharif@Forged

iTrader: (92)

Key-on-engine-off (koeo) is the position when the key is in the on position (dash lights on), but the engine is not running.

Ice, there were no threads posted on the J&S coil problem.....the people with the blown coils didnt post threads.... That's why I'm saying if those individuals choose to post..that is their choice...and if not..that is their choice too..and I'll respect that.

Oh, and I think its unfair to characterize the J&S is a pile.....it is a very good unit, and has many many successful installations on many different models of cars. I am just saying that there is a pattern of issues with the 350Z....I'm sure that John will find a solution...becuase again...I think it's a really awesome product.

AmyCroft

iTrader: (3)

I had written:
Please read the theory of operation on the J&S website...
If knock is detected on a fireing cylinder then plug will not fire on the next revolution.
This is supposed to be on a cylinder by Cylinder basis.. Amy

John @ J&S wrote back:
I stand corrected.. John of course is correct..

Amy - also of Garden Grove...

GurgenPB

iTrader: (2)

Spoke like a true genius....

I would certainly not call it anywhere within light years of that... J&S has been making this very unique form of knock control, in addition to boost and rpm-based retard, for years. It has been the cornerstone of many high power HKS-tuned 900+hp Supras, RX-7's, and many Rally cars. HKS still orders these units from J&S to this day (just the other day if i am not mistaken). Do a google search, and you 'll see. It has been highly recommended in all editions of Corky Bell's "Maximum Boost" as long as it coincided with J&S's existence (to the best of my knowledge).

I'd say do a little more research next time....

Gurgen

Happyending

So is there anyone out there that can answer my question?Is my case an isolated one?It just seems like I am hitting my revlimiter at 6000 instead of 6750..Is this how the unit is supposed to work and its detecting knock and saving my engine??

GurgenPB

iTrader: (2)

Hey

It is very likely. The sudden pull in power is noticeable when there is knock-based retarding taking place. It is MOST noticeable when I have it set to 20 deg/ALL cylinders, the power drop is VERY noticeable. So, yes, without being there and seeing your car in person, I'd say that it is likely that that's what's taking place.

Now... are you using Boost-based, rpm-based retard? If you are running a stock ECU and no other timing retard other than J&S's knock-based retard, I can almost guarantee you that what you are experienceing is J&S saving your but evry time, especially when you run 9lbs of boost. What is your a/f like?

Gurgen

IceY2K1Max

iTrader: (1)

GQ,

I was talking to the other guy, sorry.

I wasn't saying you were wrong, by any means, just that I hadn't personally read about any coil issues with the J&S, but I have seen it with the eManage on both our cars. Even one Maxima had the eManage fry his coils, he replaced them, then he put the J&S on and no problems. Later he added the J&S diodes to the eManage ignition harness and didn't burn up any coils, however he had a ghost code in the ECU keep showing up.

Anyways, I did some reading/searching, you and I are on the same page about the eManage ignition harness vs. the J&S.

I'm looking forward to seeing how far you can push the horsepower envelope with the eManage at the helm.

Thanks.

Happyending

I have eliminated detonation as the culprit..I pulled alot more timing based on boost and set the KR to retard ALL and richened up my A/F up top.It still doeas it..And its not a slightly noticable loss in power its EXACTLY like you hit the rev limiter..It goes POP POP and stutters for a second..its kind of like a back fire not anywhere a slight loss in power its a COMPLETE loss in power..I really wish John from J&S would reply to this thread or at least answer his calls...I originally thought it was my plugs but I just changed them...This really sucks...

GurgenPB

iTrader: (2)

John is probably out. If you leave him a message, he will call back (always has with me). The problem you are describing is certainly peculiar, now that iI better understand what's going on. That issue seems to be a fuel cut-off and not a timing retard, unless A LOT of timing is pulled back or the spark does not occur at all.

Gurgen

IceY2K1Max

iTrader: (1)

Sounds to me like a misfire...which could be from a couple things, however if he bypasses the J&S like John suggested and it goes away/runs normal, then the J&S circuits or installation is the culprit.

John at J&S

Happyending:

Send in your unit for a checkup/reflash.

John

MardiGrasMax

iTrader: (8)

If its too rich it could be misfire, try and close your spark plug gap?

Happyending

Will do can you tell me how to BYPASS it in the mean time..I forgot..And thanks for responding as I plan on keeping this unit on my car with my APS TT kit...PS is there a way to have 0 Degrees of rpm retard and just utilize the unit as a SAFETYNET if you do get knock as I will be using a piggyback to do all the rest..

John at J&S

Two ways to bypass the unit.

Install three paper clips in the back of the harness connector, to jumper channel one input to channel one output, chanel two input to channel two output, and channel three input to channel three output.

Be sure that the paper clips don't touch each other, or short to chassis ground.

Better way requires a small screwdriver, to loosen the screws that hold the in/out wires in the 12 pin connector. Be sure to unplug the unit.

One channel at a time, install the output wire of a channel into the same hole as the input wire for that channel (two wires in the same slot).

Before starting, write down the wire colors and pin numbers, so you can put it back.

The RPM retard is not turned on until the unit senses 2 psi. If you don't want RPM retard, and you don't need boost retard, unplug and cap off the hose from the back of the unit. The internal MAP sensor will now sense 0 psi.

ACP

iTrader: (1)

Gurgen, any problem with your coils ?

IceY2K1Max

iTrader: (1)

Oops...I forgot the 350z unit doesn't have the weatherpack connectors, but an "Interface Adapter Module". On the older unit you just remove the J&S and plug in the connectors to bypass the J&S unit.

John...can older unit(Maxima owners) upgrade to the Interface Adapter Module?

GurgenPB

iTrader: (2)

We hooked it up today with diodes, so far so good.