nycibbyryder

hey guys, so I got the headers installed in my max, and it's stuck in closed loop... the guy that installed it showed me on his scanner that it never changes into open loop whether under load, idle or WOT. He thinks that I need the O2 sims to fix it... I know the secondary O2's have no effect on a/f ratio but I feel like I'm losing mpg also... maybe it has to do with open/closed loop? any experienced opinions? I'm searching now but can't find anything... Thanks

The secondary O2's are plugged into the headers also btw.... I hope he wired it right... anyone have a diagram or know where I can get one so I can check? There's no CEL for this but he said he changed some setting in the ecu so I don't get one... doesn't really make me comfortable but I'll get to that when I figure this out. He changed the setting after it got stuck in closed loop so I know thats not the cause.

NmexMAX

iTrader: (22)

My secondaries are plugged into my primary header ports, and my primary sensors are not even plugged into anything, as in not into any ports, nor into any harness.

Maybe let it warm up for a bit, usually takes tome time before it goes into open loop. Until tehn, you'll be running very rich.




Sensor 1 = primary, sensor 2 = secondary.

Did he add new bungs for the secondaries?

nycibbyryder

yea I got the OBX headers which have 3 bungs so he moved the one bung 90 degrees and added a 4th bung so all 4 O2s are plugged in. He tested it right after I took the 20 min drive to his shop though so it was already warmed up.

Thanks for the diagram BTW I'll check as soon as I get outta work... I'm driving to Ocean City in 2 months and I'm hoping to figure this out by then lol...

maybe I'll run down there again and have him check it again... any real reason to get O2 sims other than getting rid of the CEL? Mines always on anyway bc of the stupid gas cap lol.

NmexMAX

iTrader: (22)

Seems like your set-up is fine.

What exactly did his monitor say? My guess is, he's wrong.

CMax03

iTrader: (3)

You only need to install in your Primaries and plug that last bung facing the firewall and install a Dual O2 simulator...

nycibbyryder

That'll be the next thing I do, I had my friend at another shop confirm that theory, and he doesn't like the first guy lol so I'm gonna try the antifouler trick since I got all 4 on sale for $3 lol. I forgot EXACTLY what it said, I was in the car when he tested it so I saw the scanner but it was about a month ago, just haven't paid any attention to it since my radiator blew about a week after. He may be wrong too, I thought it sounded off but I guess we'll see.

nycibbyryder

So I put the antifoulers on yesterday, fit great, drilled em out right and everything but now my ecu is showing 16mpg where before it showed an avg of 18.5 mpg... I know its wrong but if its showing 16 mpg I'm prob getting 12.... REALLY hating on the fact that its sunday right now and I cant just run down to a shop and see whats up.... sunday is such a useless F*cking day... and it's windy... f*cking hate wind right now too... sorry just kind of annoyed with this car right now I just want it to f*cking work...

I put em on the o2 sensors that have 4 wires, I'm pretty sure the ones that have 3 wires are the primaries. My harness colors are different also, pretty sure theyre aftermarket.

Remember I have OBX headers so placement of where they are mean jack sh*t

nycibbyryder

According to this I plugged them into the right ones. Went to auto zone, no codes except the stupid gas cap. Can someone verify that the rear o2 sensors in the 02-03 max has 4 wires and the fronts have 3? Just want to be sure.

Edit: now it's showing 15mpg... Dafuuuuuuuuuq...

NmexMAX

iTrader: (22)

This is true.

Fronts are baby blue too.

nycibbyryder

K so I guess I did it right, I just filled up and reset my trip meter so I guess I'll run her to 1/4 tank, fill up again, n see what the real difference is. do we normally get a drop in mpg like this after headers?

NmexMAX

iTrader: (22)

Never noticed a drop in MPG's after headers. And if I did it was due to driver-mod.

02whitemaximase

iTrader: (38)

OBX headers makes the o2 sensor situation real easy for us? Just plug the rear bank primary port and have it repositioned 90 degrees. Both primaries go basically in the perfect condition equally upstream on both banks. DO NOT plug the rear primary bank and install the primary sensor in the next port down. That is ridiculous and just plain lazy. If you do that then you loose the port for one of your secondary sensors and the primaries would not be at equal distances from the head. I have this exact setup with the doubled up anti fouler trick for both secondary ports. No cel for thousands of miles and MPG was not hindered.

nycibbyryder

my 2nd post...
good to know, so it does work, I just gotta figure out what else is wrong then I guess... Only thing I can think of is it's either wildly inaccurate right now and nothing actually changed, which I'll find out after this tank runs low and I refill to figure out the actual mpg, or, now that it's in open loop (if it is) it's pulling readings from a faulty O2 sensor... either case I guess I need a scanner to play with to figure it out... and some time...