here is the notorious big 8:

0803- Manifold absolute pressure sensor or circuit fault
1302- Manifold absolute pressure solenoid valve or circuit fault
0801- Vacuum cut bypass valve of circuit fault
0402- Fuel tank temperature sensor or circuit fault
1305- Fuel pump control module or circuit fault
0903- EVAP canister vent control valve circuit fault
1008- EVAP canister purge control valve circuit fault
0807- EVAP canister purge control valve solenoid

ok, this is the scenario:

i'm running a 95 max 5-speed with pretty much all the mods i can get for bolt ons. now i'm ready to do some engine work. i recently slapped on a mevi and a pathfinder throttlebody. runs fine and everything. but what good does it do without the ecu, right?

so i bought this 96 JWT ECU w/7200 rev limit. put that puppy on the car and it gives me the "EVAP 8" codes shown above.

i searched and a few of the orger's got these codes, too. but no one ever got around it. Now, after much debate and research, my observations are listed below:

1) Not all 4th gen maxima's have the same emission equipments. We all know that. At least I also know that there are the upper gen and the lower gen of the 95 5-speed models made:
upper gen=manufactured after 07/94
lower gen=manufactured before 07/94

the difference between the two are hardly distinguishable. The flywheels, for an example, are different. That's why some 95 5-speeds would have issues with the fidanza flywheels, which some distributors claimed perferct fitment for all 95-99 models. However, the lower gen 95 maxima will have fitment problems. I am a prime victim of such case. I had to buy a stillen flywheel to get-r-done.

2) EVAP system for a 95 is different than the 96-99's. i have 5 maxima's sittin at home right now, and from observing them, here is what I got:

a)96 auto (wrecked) electrical evap equipments
b)95 auto (running) canister evap equiments
c)96 auto (running) electrical evap equipped
d)97 auto (running) electrical evap equipped
e)95 5 speed (running) canister evap equipped

the electrical equipped evap would have more items to run the vacuum lines and such. the canister is located near the rear left tire.

the canister equipped evap has its canister sittin under the brake booster. it runs in conjunction with the solenoid purge control valve, and that's it.

3) ECU's on the 2 different evap setup is still compatiable, but will yield the codes, "the EVAP 8"
I'm not sure what the situation is with swapping ECU's between maxima's and I30's, but for ECU's programmed to run on these two different set of EVAP's, it sure will pull the 8 codes. one way or the other.

4) The codes "EVAP 8" doesn't seem to have much defects on the performance of the car. I still think the car runs as great as it has ever been. It's just that engine service soon light is bothering the psych out of me when i drive. After all, this really doesn't contribute to any power loss in my assumptions.

Now, with enough said, this topic hasn't been tinkered by anyone. But does anyone know of a way to by-pass those codes from a electrical EVAP ECU to fit on the canister EVAP ECU?

 

Why didn't you get a proper ECU for your car to begin with? Easiest way to fix this problem is to send JWT the factory ECU out of your '95 5 spd and sell the JWT ECU you have, while its still valuable...

Trying to fix codes like this is not difficult for a electronics person, but why waste your or their time?

 

you are right. me and my bro were just talking about this yesterday. the reason why i didn't get the right ecu the first time is because i didn't know about this thing. it's always trial and error to learn things like this. although i did some research on the org, not many people mentioned this here. those who mentioned didn't point out the problems. so i end up screwed. i got this ecu off taken2damax. he said the ecu ran perfect with him and it is perfectly compatiable with my 95. however, no one expected this evap difference.

yeah, i'm thinking about what you suggested. I might send in my 95 ecu to get them reprogrammed, and try to sell the 96 ecu after that. i kind of want to do this because i want jwt to do my ecu my way. since i did so much N/A mods for my car already, I might want the ECU redone to work best with my setup.

thanks for the advice

 

JWT only has two NA 4th gen programs. Actually, I'm not even sure if they have two. If they do have two its because of the VI. They will not custom make an ECU program for you unless you go to them with you car and slap it on the dyno. That will be big bucks.

As for the EVAP, I've pulled out the charcoal cannister(I'm early 95) and have no codes. Currently, I get some issues with gas burbling out of the unplugged hardline. This happens when my exhaust heats up the fuel lines. My exhaust is currently ending in the tunnel right before the tank. But all that doesn't really help you.

Except the 0402 - Tank Temp. I really don't think the early 95's have this. Unless the temp sensor is integrated into the level gauge I don't have one. I don't think it is integrated because there are only two wires in that harness. So, to solve that problem I would A: Buy a new Tank Temp sensor and run a harness to those pins in the ECU. or B: Find someone with a tank temp sensor. Measure the resistance of the sensor and then put an appropriate resistor in a short harness going into the correct ECU pins.

Also, the absolute pressure codes seem odd. I have removed my MAP/Baro switch and haven't gotten a code for it. You could fool the ECU in a similar method to solve those codes. That is unless the ECU looks for a fluctuating value from that sensor rather than just any value(Like an O2 sensor).

Similar things could be done for the EVAP control valve. But at some point you really wonder, "All this to get rid of a d@mn light?" IMO, its not worth it. Just live with it. My CEL has been on since I began driving this car 2.5 years ago. Its never been for a serious or performance robbing issue. You just learn to live with it. At least it isn't red. The orange makes it less annoying. Now the Airbag light has been on for the past couple days and that is really p!ssing me off. I'm gonna be unsoitering that one this week.