OK, I think the cat is out of the bag on this crank angle sensor wire issue. APS has posted a detailed schematic on their website, so I feel this should be read by anyone that is running F/I on their motor. Especially those are building some very expensive forged motors.

There is some speculation, and apparently some testing by APS has confirmed this as well....that there is some kind of interference or anamoly with our crank angle sensor wire. Essentially, there is some noise in the signal that goes to the ECU, and under certain circumstances, this can generate a false or muddy crank angle input to the ECU. Obvisouly, if this happens, there is a chance that the coils may fire before the pistons are at TDC, and could contribute to detonation/preignition. Peter has also described this as "scattered ignition timing". It is something that occurs only under certain conditions, and only on certain cars. Some cars exhibit no anomolies...others do.

But APS felt it was important enough to include a new shielded crank angle sensor wire in their kit. You can see this on their website.

So...just to be safe, it would be HIGHLY ADVISIBLE for everyone with the Greddy and PE kits to immediately swap their unshielded crank angle sensor wire with a new shield wire. I would hate to see these new forged motors start blowing up due to this potential problem.

I was also thinking that some diodes on the line would also be helpful...what do the electrical experts think?

 

D@mn . . . I was wondering if anyone would say something about this for quite some time. My main question is:

Who wants to make a shielded wire for us ? I don't think APS intends to sell that piece, but if they do, I'll sign up for that group buy

From my understanding of the issue, the ECU misinterprets the noisy input and advances timing way out of spec. Result: huge spikes in your cylinder pressure that your rods cannot absorb I'm sure there's other electrical theories at work here, but for us laymans, just know that the preliminary info points to the unshielded wire.


G

 

You can make it yourself. Just unplug the wire from the sensor, and disconnect the wire from the ECU. Cut and replace this wire with a quality shieded wire.

I am curiosu if APS put some diodes or anything else in their wire.

 

he's one smart dude that peter fropm APS..................I should know he trained me for 5 years.

Yeah it's called scattered ignition timing and normally this left unresolved ends up with a piston hanging outside of the block.

Best get this problem sorted quick smart.

Send Peter a email at APS and maybe he can work out a quick solution.

Georgec

 

In addition to shielding, it looks like they rerouted the wire to alleviate any issues . . .

Anyone have an APS kit that they can look at to inspect the wire (to see if there's anything else besides shielding)?

Wish Peter was here to help . . . Is he still banned?

G

 

I still can't believe he got banned....its times like this his input would be more than appreciated.

I'in on this group buy if it happens!

 

I would expect that the OEM ECU already provides some form of integrated diode clamping at it's input, to protect against ESD and other overvoltage transients. The shielded wire appears to be a sound solution. I also seem to recall that on some 2003 G35s there was a TSB to replace imtermittent crank angle sensors which may also cuase similar problems.

 

i've heard and remember seeing that wire on the plug and play set up on the aps TT system. i didn't know that aps would let everyone know that they have found out what may be causing some perfectly tuned motors to blow. thats good though. hopefully everyone gets it taken care of, so no one else blows there motor from this.

the only thing i wonder is, i guess nissan wouldn't even entertain any damage from this being covered by the warranty if your car is equipped with FI?

interesting find for sure!

 

Many have known of this find by APS for quite a while now... but for some reason it was requested to remain a secret. Well its simple enough, its just a shielded cable that goes all the way from the sensor to the ECU plug. It will be simple enough and inexpensive for those of you to perform this mod.

APS provides a plug and play for this with their kit... but you do not need the plug. The manufacturer of this plug doesnt appear to be Sumitomo and its probably gonna be a hassle to get your hands on... might as well just cut the plug off your stock harness and go from there.

here is the cable that APS found to be the solution:
http://www.lapplimited.co.uk/product.../uni_liycy.htm

I beleive part # 0034 603 on that page should be the same but someone else should check on that before people start buying it.

this is simple enough for everyone... replace the wire starting at the plug and run it all the way to your ECU plug. I spent a hour calling around about this connector... its appears to be a company called Arrow that I cannot find... but it doesnt matter really just use the connector already on the car and cut if off.

This find by APS is the real product of R&D in their turbo system... if they didnt pick this up on the o-scope... it probably would have been a long long time before anyone else tried looking there... everyone else wanted to blame weak internals.

When doing my fuel system R&D on the 350z I realized that APS did their job... they didnt just slap a kit together... they tested their product and vehicle to find out what it really needs other then a turbo stuck on a manifold. We were bench testing the components of the fuel system and sliced up a pump assembly to verify its inner workings and thats when I said... gee... all the people with this AAM return fuel kit are never gonna get to use more than one side of their gas tank with this stupid plug that replaces the fuel pressure regulator... you need the fuel returned to that location to power the siphon jet... so then I say hey I think APS has their installation instructions on the website lets see what they did with their fuel return... we were assuming it was going to be rigged as well... well nope, we found the page and i said to myself "****... these guys werent ****in around, they bothered to actually find out that their fuel system is functioning correctly"

i said in a post a while ago that the APS kit will give 350z's the HP that other kit owners will blow their engine trying to obtain. Crank trigger interferance and dropping fuel pressure when your gauge says you have 1/4 tank is whats going to kill other guys every time.

APS kit gets 2 thumbs up from me.

-Charles

 

phunk I know that peter would have spent many hours on the fuel system design and scoping the engine to sort out any crank sensor signal/technical issues..................he's been around the turbocharging scene for a long time (about 30 years) and there's not many problems he had not encountered over that period.............he's one clever dude that peter.

I know that peter would be happy for the Z owners to share in this info and I expect this info will save some engines from exploding.

george

 

Hmm I found the manufacturer of that connector and a source in the USA. If anyone cares for the crank trigger plug to build the harness, ill see if i can get you in touch with a supplier just PM me. Something mislead me into believing that it was made by a company I never heard of... but I did in fact happen to run into it and its by a common OEM connector manufacturer.

 

Wow thats some scary ish...I wonder if this would affect reflashed ECUs as well. I'm sure TS has not taken this into account and I'm not sure they could. I would be interested in a pre-made plug and play replacement.

 

Lets not get too excited in thinking this is the magic bullet solution that will let you build monster motors with TT.

This is just one of many variables that may or may not be contributing to the faillures of some of the other kits.

And although I believe the APS kit is the most complete and best developed kit out there, only time with tell....as to its effects on our stock motor.

I cant just see it now....people adding "shielded crank angle sensor wire" in their sigs.

 

You'd be surprised. In the Later model Sentra world a common sig mod was Grounded Knock Sensor, relocated O2...Those were problem items for those cars.

 

So this thread is a bit over my head guys. Can someone please answer me this?

1. Can this affect all 350z's, NA, SC, and/or TT equipped or just TT'ed ones?
2. Is this something we should be petitioning Nissan and getting them to do something about?
3. Is there any downside to implementing the mod? I mean, what's the chance of a qualified mechanic botching the job and causing you more problems then you are trying to solve?
4. Just wondering if us Vortech guys should be looking into this as well. I have thrown the CEL once, could this contribute?

If this makes sense, tell me how much and where to send and I'm all for it!

Thanks for all of the info! Awesome forum!

Chris

 

I think that the biggest concern is for anyone running a set up where timing is critical to keeeping the engine alive ( high compression or boost ). It seems to be a simple mod.....just have anyone who is electrically gifted do it for you.

 

Interesting. The Stillen superchargers engine management taps into the crank sensor right at the sensor itself. I wonder if that's why no stillens have blown yet, or would it be worthwhile for me to do also? If so, I guess I would want a shielded wire from the crank sensor, to my eng. management and back and then to the ecu.

 

Apparently the APS kit not only replaces the wire but takes over the entire function from the stock Nissan ECU.

Perhaps replacing the wire is not enough.


See thread in 3 5 0 z - t e c h forum

Can't post link here, site filters it out.

 

Can't post link here, site filters it out. [/B][/QUOTE]

Wish we could filter the site out of this forum I petition this site to allow Peter ( APS ) to come back here if he even would. If the people "care about and love our cars" as much as I have heard expressed...shouldn't be a problem. Right?

 

Stillen's SC haven't blown any engines because they are not making insane power like TTs and Vortechs.