Slamrod

iTrader: (11)

Got a quesiton about what exactly triggers the safe mode/ timing retardation in these cars. Im referring to the one generally related to the knock sensor being bad where the car feels sluggish, NOT the one related to MAF problems that doesnt let you rev over 2500rpm.

Will EVAP or EGR codes result in this safe mode being triggered? As in, will it also trigger the "ghost" knock sensor code that makes the car run slower? Ive been doing some searching and ive found some posts saying it will, but these people also had codes related to o2 sensors, which 100% will trigger the knock sensor.

To my knowledge these conditions will trigger the timing retardation:
-bad knock sensor/engine knock (duh)
-bad o2 sensors, or readings that are too lean/outsid of parameters
-low octane fuel, which i suppose relates to the first two
-spark plug/coil problems
-possibly injector issues as well?

Is there anything to add here? Most importantly, are EGR or EVAP codes part of this list? To me it would seem it only has to do with ignition related systems.

The reason i ask is because i have a 96' JWT ecu i want to use, purely for the 7200rpm fuel cut as i already have an apexi neo and wideband wired in. However, i have codes relating to the EVAP system, and considering that im lazy and just swapped in a 95' fed spec ecu to bypass those codes rather than fix the problem, im concerned about how the car will run when i swap the JWT in.

I really dont want to fix the emissions crap - egr tube is already welded off and soon to be deleted entirely as im in the process of putting cattmans on the car, and ive read nothing but grief about hunting down EVAP code causes so id like to just rip that silly crap out of my car as well. However if this will result in the ghost knock sensor code/timing retardation, itll basically make the JWT ecu i have useless for me.

Anyone able to shed some light on this? Much appreciated.

lux97Max

iTrader: (24)

Ive pretty much almost replaced every hose/mechanical sensor involving evap and egr. Ive never got a knock sensor code. If the air flow of your evap system is not flowing correctly it 100% effects the driveability. What are your evap codes?

Slamrod

iTrader: (11)

I already have the 95' ecu in so the codes are gone (didnt i buy this off you? Lol) but IIRC the code was 0704, blink code not scantool code. Its been a while but that code sticks in my head.

If i deleted the whole evap system or just blocked it off, wouldnt that eliminate any potential performance problems? I could see it being an issue if i just left everything as-is, but if that system is sealed off, wouldnt i be ok to go?

If it turns out to be an easy fix, then hey maybe ill fix it. But honestly im not concerned about the codes, more so the cars performance. If i could get away with just deleting the system and running the 96' JWT without performance issues, and spending an afternoon once a year to swap in the 95' ecu for inspection day, thats 100% ok with me.

lux97Max

iTrader: (24)

Only way to know for sure is to block it off and see what happens trial and error is a *****.

schmellyfart

iTrader: (46)

Well the codes aren't going to go away if you rid out the EVAP system, its possible the you just hooked it up incorrectly when you installed the dek. The FSM has a good list of things to check for each code in the EC section.

Slamrod

iTrader: (11)

The DEK was actually done by the previous owner, along with the egr delete. Im 100% not concerned with having codes at all, i have a scan tool that i can periodically pull codes with to make sure nothing else is wrong.

My only concern is whether or not these codes will cause issues when i install the JWT ecu. Which goes back to my original question about getting a knock sensor related code that piggybacks alongside the evap code. If the entire EVAP is removed/physically blocked off, and there isnt a knock sensor ghost code, any other code that comes up doesnt matter to me lol. The 95' fed spec ecu i have currently in the car is for inspection passing, and the JWT is for performance - whether or not i can pass inspection with the JWT (and by extension evap codes) doesnt matter to me lol.

Actually troubleshooting the EVAP is pretty much my last resort - id be more happy to sell the 96' JWT and just shell out the money for my 95' ecu to get a daughterboard installed, rather than pay money to fix an emissions system i dont need to begin with via the 95' ecu.

maxprivate

iTrader: (12)

I doubt the fail safe is triggered at all by the EGR system. I had an issue with fail safe mode and it was because I did the 2001 AE cluster swap in my 97. I would occasionally go into fail safe but i think it was due to the difference between the VSS in the 2001 and 97 maxima.

With the cluster swap there is a delay when the speedo would register any speed at all. Until I hit about 10 to 15 mpg the cluster would then display speed. This was normal in all 4th to 5th gen cluster swaps.

I eventually got tired of the fail safe tranny issue and swapped the stock 4th gen cluster back in and blaammm problem solved. Never went into fail safe again.

I would just delete the EGR, your problem is something else.

In addition, EGR system so sensitive and tough to diagnose as you mentioned. Most times people replace good parts in hopes of making the code go away which is a waste of money and time. Delete it, one less thing to worry about. Good luck