Also, just to keep everyone updated on all my little bugs. I went WOT and brought the engine above 4K rpm today for the very first time. My AFR seems to be stuck around 14.5:1 until I get above 4K rpm. So, the engine just bogs and doesn't make any kind of HP until 4K. Then at 4K rpm, the AFR goes to 12.5-13:1 and in 1st gear, the tires light up from a roll. Same thing happens in every gear. It bogs first, then takes off once the AFR isn't 14.5:1. I just wanted to let everyone know the issues I'm having.

I feel the TCM shifting issue is completely unrelated to the AFR issue. My fuel pressure it set at 51psi and doesn't change at all during my WOT run. Does anybody have any ideas why it might bog like that? I'm not 100% sure that it's staying in closed loop up until 4K, but that's what it appears to be doing according to my wideband.

 

what is the voltage range on your wideband, is it possible that the motor is running leaner than 14.5 and the wb just can not read any higher

also what is your vac at idle, wot and de-accel

 

My wideband voltage range is 10:1 to 20:1. I have a PLX M-300 wideband. I found them back when they were very new. But it's still working after all these years.

As far as vacuum, I haven't bothered to measure it. Why would it be important?

 

leaks intake and exhaust will throw off your a/f and by checking your vac it's a easy why to see whats going on with your engine

http://www.secondchancegarage.com/public/186.cfm

 

Aaron! I finally got my comp fixed (thanks streetz!). Nice videos meng and congrats on finally getting it together and running smoothly!

BTW to those saying that it sounds much better like that with open headers than with the cutout...

Mind you that the reason open cutout sounds so nasty on most maximas is because of the y-pipe. Most maxima folks have an un-equal length'd y-pipe. This is a major cause of rasp which is heard very clearly with a cutout lol. You do not hear it anywhere as bad with an equal-length ypipe. If he puts an equal length ypipe on this car, open ypipe will sound just like it sounds with open headers. Not all raspy and nasty as it sounded before with the old y-pipe setup.

 

Thanks. I don't think I have any intake leaks. But I will definitely check the vacuum then. I have a gauge as well.

Thanks. My Ypipe looks very close to yours. He also had to cut the flange on the RH header to raise it up a touch. Then, he had to loop the exhaust around and merge it. A good chunk of my control arm had to be cut as well, which I already knew before visiting the exhaust shop.

I haven't bothered to open up my cutout to compare the noise yet.

 

Question regarding your issue. You have your o2 sensors hooked up, right? If you do, just to test, disconnect both o2 sensors and drive again, go wot, see what your a/f is showing, and see if it still bogs. Just to test things out n see wats going on.

 

Yeah, I have both o2 sensors connected in the headers. Those are known as o2 sensor 1. The o2 sensors #2 are not connected and aren't required.

But, I can unplug them to see how my AFR is effected.

Also, I just talked with Jime. He told me that he noticed that the engine would bog below 4K just b/c the ASCD switch is preventing the throttle from opening fully. Unplug that switch and it allows full throttle position even below 4K. So I hope that solves my issue.

 

Oh well. I just tried unplugging the ASCD signal from the ECU and no change. The car is VERY slow below 4K no matter which gear it's in. When I say slow, I mean that any Civic could beat this car. But when I hit 4K, the tires light up in 1st gear! I don't know what can be causing this. And I highly doubt it's TCM related.

 

Aaron try logging your timing with your obdii as see what it is below 4k.

 

Good idea. I'm not sure right now if it's yanking timing or reducing throttle position. It's so rainy outside that I think it'll have to wait until tomorrow.

But, I tried removing the tach signal from the TCM all together and there was no change. it still shifts at those speeds, 20, 35, and 55mph.

 

Update: Since I can't figure out this TCM issue I'm having, I just placed my order for a Suprastick. I will run it full standalone. I just hope it solves my issue. I can't wait to finally run through the gears at WOT!! The most I've felt from this engine is a short acceleration burst from 4K to 5K in 1st gear (lit up the tires!) and a short burst from 4K to 6K in 2nd gear (felt just like my 75 shot of nitrous on the VE). I don't count any time I've spent below 4K though since that is a COMPLETE DOG! Something electronically is holding me back below 4K.

 

Your going to love the suprastick, just make sure the problem your having is not going to be the same case with the suprastick, for example a signal being inaccurate like speed, tach, tps, etc..

 

Alright. It's time for more pictures.

Here's when I first fired up the engine:





On Friday, I got the custom mandrel equal length Ypipe made. I had to drive just under 1.5 hours on open headers to reach this exhaust shop, but it was totally worth it! First off, it's the only place in North Carolina that has a mandrel bender on site. Second, this guy obviously knows what he's doing! I highly recommend him for anybody in the Raleigh area.

RJ's Custom Piping
http://rjscustompiping.com/

If you need mandrel U-bends (aluminum, steel, etc), tell him I sent you! His pricing is very competitive and he has little overhead in order to keep the prices very low! And I did not recieve a discount to help promote him, he just did a great job and greatly exceeded my expectations! Plus, he's a Nissan enthusiast.





We had to raise the flange of the cheap ebay Altima 3.5 RH header in order make more room. Plus, the 3rd gen RH control arm crossmember studs and the CA bracket had to be cut as much as possible since there was no way to get a Ypipe in there after having the 4th gen crossmember in the exhaust area. It's not a big deal. Just take a sawzall to it for 5 minutes and call it a day.

 

Thanks. I am very confident the speed and TPS signal is accurate. I've measured those. Plus, they are the same wires Jime used. The RPM signal probably won't work though. Not the one on the 3.5 engine. But the good thing is, is that the Suprastick only needs the RPM signal to keep your from downshifting into a redline situation. So if you know how to drive your car, you shouldn't ever try to downshift into 1st gear at 60mph.

 

cool pics.

 

Too bad the stock TCM wouldn't work out, but I think the Suprastick will be a neat upgrade. You sure it isn't perhaps a missing ground or something for the TCM though? Anyhow hopefully the Suprastick thing is a quick install so you can get to work on your tuning! Oh and check your email for the pics/video I took on friday at RJ's shop.

 

nice ypipe!!!! :-D how do u like the sound of a ballsy engine there broah?

 

looking good!

i'm not sure your exact issues but i just wanted to share that my 3.5 swap does the exact same thing....at 4000 the engine comes alive...below that its not very impressive.

good luck getting it going!

 

Yeah, I'm sure I am missing a wire or a proper signal on a certain wire to make the TCM happy. I did check all the ground and power wires and they are all ok.

I am running the stock VE catback exhaust with a cutout in place of the stock cat. There has always been a small exhaust leak right at my cutout if I don't take the time to clean it and apply fresh Red RTV to it. But the RTV actually providing a good seal seems to only last a couple months. So b/c of the small leak, I get a really bad rattle sound when I give it anything more than 25% throttle. It sounds horrible. But I don't really care how it sounds as long as my engine and tranny is running perfectly. I may worry about the sound some time in the future when I finish working out all these bugs.

So at 4K rpm, how much extra power do you feel? For me, below 4K, my AFR is around 14.5:1. When I hit 4K rpm, my AFR immediately goes to around 13:1 and it's EXACTLY like I activated a 50-75 shot of nitrous!! No joke. My problem isn't a normal powerband of this engine. When 4K is hit, you better be holding on to the steering wheel cause the tires light up instantly. It's a pretty good kick in the face when 4K is reached. It's easily an instant increase in power of over 50hp.

Does yours feel like nitrous being activated? Or does yours just come on a little more gradually? Are you running the 5.5g ECU?

 

The 3.5 isn't too much of a slug under 4k rpms. It's nothing compared to above 4k, but it's not sluggish under either. I still have a good amount of torque, but screams after it hits that crossover point. Although it might have something to do with me being a 6-speed as well.

Have you driven Darren's 5.5gen? Does it feel similar to that, or does it seem to just not have any power under the 4k mark?

 

i think its your SSIM and Vias, work.


<4k no good. >4k beast

 

I've driven my friend's 3.5 Altima, my dad's 3.5 Quest and both will spin the wheels from a stand still in 1st gear EASILY. My goal won't spin the tires from a standstill. So it's definitely something electronic. I'll check out the timing first to see if it's being retarded below 4K. It's NOT the engine itself. I can guarantee that one. This engine is a BEAST. But it's something to do with the ECU pulling timing to restricting the throttle plate from opening below 4K.

It feels way worse than my VE did below 4K. But when it hits 4K, there is an INSTANT 50-75 extra HP. If you've never felt the kick that nitrous gives, then you won't know what I'm talking about.

 

It's NOT the engine or the fact that I don't have VIAS. I've never been more certain. It's electronic. The SSIM or VIAS won't make you lose 75 HP and then suddenly at 4K rpm, make it feel like someone just REAR ENDED you b/c the car takes off so fast.

 

hmmm



so i guess only thing it could be is something with the factory ECU??

 

how bout this hypothesis: car running too lean under 4k, which is setting off the KS which is retarding the timing and then after 4k it goes to open loop and richens up which stops triggering the KS.

 

prolly soo




AARON.......


UTEC...... lol i know you know, what i know.

 

I just got back from the post office while logging my RPM and Timing Advancement. The car revs SOOOO fast even doing a 2nd gear pull, that I can't get any data from it. By the time the ECU sends those signals to my Auterra software through the OBDII port, I have already let off the throttle cause I was going too fast. All I end up seeing is a spike in the graph. Maybe Dave has some tips for me since he's used this Auterra DynoScan software more than I have with the 5.5g ECU.

Well, last night, I unplugged my battery. I plug the battery back up for the first time today and HUGE difference! If I manually shift, I am able to bypass those predetermine shift points due to the TCM not operating properly. Sure, the car doesn't make all that much HP below 4K, but today was MUCH better. It still will spin the tires pretty easily on the launch at half throttle. Then I was able to go WOT right around 3500rpm in 1st gear without much traction loss. But as soon as it hit over 4K, the tires just spin all the way through 1st gear and when I shift VERY early at 5500rpm, I just do a LONG rolling burnout going into 2nd gear. This car is producing WAY more HP at 5500 rpm than my VE ever did with a 75 shot! And I really don't think I even got into my peak HP range yet. That will probably be above 6K.

But, it is TOUGH to manually shift this car while doing a 0-60mph run through 1st and 2nd gear! I can't keep the thing on the road. I thought my car was fast with the 75 shot, but this thing easily blows it out of the water!

Oh yeah, with the cooler weather today (mid 60s), for some reason, my AFR at WOT is now in the high 13s. It's a tad too lean for me. I'd rather see it in the high 12s for NA runs. Does anybody else see lean AFRs with headers, SSIM, cams, etc?

 

What gear(s) were you monitoring your afr? FYI, the lighter the load, the leaner the reading. The afr needs to be monitored with a high engine load.

 

I have always looked at my AFR everytime I get on the gas. 1st, 2nd and even bottom of 3rd at WOT (highest load), the AFR is in the high 13s and low 14s.

 

I raised the fuel pressure from 51 to 60psi and even though I'm still running slightly lean (low/mid 13s), at least I'm not close to 14:1 anymore.

Also, I may fiddle with my cruise control some more tomorrow. I need to get that working somehow. Jime said his cruise only works with the torque converter locked up. I don't know how that works since the ECU doesn't get any signals from the TCM or SS. So I don't know how it would know if it was locked up.

But, when I go to press the ON button, the Cruise light comes on and the SET light blinks rapidly. It even blinks all by itself when I haven't pushed any buttons. I just have to go through all my wiring again. I'm sure I'll figure it out somehow.

But has anybody else ever had the SET light blink before when the ACSD malfunctioned?

 

If the ECU is pulling timing, have you considered grounding the knock sensor so you get full timing throughout the rpm range?

A few 5.5 gen guys (and Jime) have done it.

 

i might've missed this.. did disconnecting the battery restore power under 4k? or did raising fuel pressure help any with that? how's it feel now that pressure is up? and how's the AFR over4k/wot?

 

Yea aaron did you try this yet and are you using a new knock sensor or maybe a old one that came with the motor?

 

No I haven't. But, my problem went away after resetting the ECU.

The AFR that I mentioned already is above 4K. Low/mid 13s. That's after the raise in fuel pressure. Before, it was high 13s and even cracked in the 14s at WOT sometimes.

I used the stock 49K mile old KS.

I'm not too worry about this problem now that it's gone after I reset the ECU. I'm more concerned now with getting my Suprastick and finding a way to get my UTEC working.

 

Never assume. I do this weekly. Sorry I didn't think of this Aaron.

 

This car is such a beast! I know I keep saying that without video proof. But I will try to take a quick in car video soon.

But, I can see why Jime wasn't concerned about spraying. He was having plenty of fun NA! For me, 1st gear is a complete joke. And if I go WOT and shift into 2nd gear at 5500rpm, it just does a LONG rolling burnout going into 2nd gear. I never got my 75 shot VE30DE to do that. In fact, I was able to get the tires to hook up on the 75 shot in 1st gear most of the time. The engine is producing a lot more HP though. I can't imagine what would happen if I attempted to shift into 2nd gear at WOT around 6500rpm!

If I did attempt to spray nitrous on the street, I wouldn't be able to spray until about 60-65 mph and it would have to be a very small shot to keep the tires from breaking lose. Don't worry, I'll get some more videos up soon!

I still couldn't fix my ACSD this afternoon. I did find a bad wire going from the ASCD module to the ECU. But after fixing that and clearing the codes, it still doesn't work. The code doesn't come back though. But when I press the ON button, the cruise light comes on and the SET light just blinks.

What would happen in a normal 5.5g Maxima if you pressed the ON button at 20mph? Would the SET light blink since the speed is too low?

 

The 4k power surge is simply a function of the intake manifold whether it's the SSIM or stock w/ block-off plate. It's just exacerbated with the SSIM.


Glad to hear it's up and running Aaron!!

 

Its like your teasing the heck out of us lol. Glad you got it up and running man.

 

Open loop occurs before 4k.