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JIm Wolf ECU issues


BlueZ31

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Hello all,

 

Just got back from a dyno session today, 160.6whp and 184wtq on my N/A '87, not too bad HOWEVER, as the dyno technician pointed out, my AFR was very lean (15.7!) all the way up until about 4100rpms ( I will try and post dyno charts once I find a scanner), where it dropped down into the 14/13 range. The HP curve was smooth, without any hiccups, as was the TQ curve. I called Jim Wolf to inquire about the lean AFR situation, and the technician was not helpful whatsoever. He kept blaming the AFR (exhaust tip mounted style, I know tend to read lower) saying that if my car was really that lean it'd be detonating, also saying that the dyno tech was wrong in thinking that 15.7 is too lean for an engine. What!? I asked that if I got tests done on the AFR at another shop and it was just as lean could he help as far as reprogramming/fixing the tune on the ecu, and he immediately changed subjects, only to repeat himself. Eventually I got fed up and ended the call as politely as I could.

 

How lean is too lean? I know that with my list of mods I should be seeing a bit more power, and I am very dissapointed with JWT's handling of my questions. Anyone else have similar issues? I'm getting full fuel pressure, and the car has 0 vacuum leaks or issues.

 

Mods are as follows:

Bored .040,tubo oil pump,Isky cams (256 dur, .425 lift)/ Russ's gears, slightly worked heads,engloids plenum and 240sx throttle/fresh(and adjusted!) TPS. Jim Wolf N/A ecu, headers/Magnaflow cat/super40 muffler.K&N filter, electric fan/nismo t-stat.Walbro 255lph pump, fresh fuel filter/press regulator, fresh plugs/wires/cap/rotor/coil. ACT clutch/resurfaced flywheel.Maxima alt/Optima redtop.Injector factory service campaign.

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Majestic motorsports in Jacksonville N.C. They do nothing but performance work, regularly imports (they have vids on youtube of a extremely fast drag supra) especially Toyo's/Nissans/Subies (there were 2 R35 GTR's there this past weekend).

 

As for the shop being wrong? I doubt it, highly. I was with the vehicle and the tech the entire process, and watched everything meticulously (my Z is my baby!!) The import crowd I run with here often go there strictly for dyno sessions, and all have had excellent results. The shop would have nothing to gain by feeding me false info on my vehicle from a dyno session, and all of their equipment is new as their old shop was destroyed in the recent hurricane, which forced them to rebuild.

 

As for JWT being right? Maybe, but it doesn't forgive the run-around recieved over the phone, especially when I've shelled out $$ to them for valvesprings and a ECU which aren't cheap, and considering I was polite and professional with them on the phone. I can entertain the idea that Majestic's was incorrect, but I really doubt it. People have complained about MM, but most of the people to do so had engine work/nistune/standalone ecu mapping etc. done by tech's that are no longer a part of the shop, because they screwed the pooch one too many times.

 

Regardless the last post didn't really help answer my original question, and I would greatly appreciate someone giving me a hand.

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I don't see what injectors you are running. If you have stock injectors, the JWT is undoubtedly tuned for higher than stock flow, and 290cc (stock) injectors would be understandably lean.

 

Oh, anything over 14:1 is way too lean. I would think you'd need an AFR in the mid-12s for maximum power.

Edited by SleeperZ
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Stock 180cc injectors, but JWT has the ECU programmed for the stock MAF/INJ. Cobra MAF and larger injectors are options, but my ECU isn't programmed as such. 12 seems more on the rich side, are you thinking my car is a turbo? Anyways, thanks for helping slightly solve my question.

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Stock 180cc injectors, but JWT has the ECU programmed for the stock MAF/INJ. Cobra MAF and larger injectors are options, but my ECU isn't programmed as such. 12 seems more on the rich side, are you thinking my car is a turbo? Anyways, thanks for helping slightly solve my question.

I realize your car is N/A, but the Z31 stock injectors I thought were all the same flow as the 280ZXT, turbo or non.
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Oh ok. I wish, but no they're 180cc. Im half tempted to go to a local junkyard and replace this JWT crap with a stock ecu, as I know they tend to run more rich. I'd also be half tempted to do another dyno session and if the stocker puts down more than the JWT he'd be forced to shut his trap and rework the damn thing.

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As I had wondered - your post is really a complaint about how you were treated on the telephone, not a technical question. Should probably be in the Non-Tech forum, if allowed at all.

 

Why don't you call back and try to talk to someone else before you trash the whole organization and their products? Maybe you got a bad apple.

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"160.6whp and 184wtq on my N/A '87, not too bad HOWEVER, as the dyno technician pointed out, my AFR was very lean (15.7!) all the way up until about 4100rpms ( I will try and post dyno charts once I find a scanner), where it dropped down into the 14/13 range. The HP curve was smooth, without any hiccups, as was the TQ curve"

 

"How lean is too lean? I know that with my list of mods I should be seeing a bit more power, and I am very dissapointed with JWT's handling of my questions. Anyone else have similar issues? I'm getting full fuel pressure, and the car has 0 vacuum leaks or issues."

 

Not a technical question? You're right on one respect, I am dissapointed with the handling of my issues by JWT, but as stated repeatedly, I was more concerned that the AFR was too lean, and whether or not anyone had similar lean-out issues on their vehicles, and what the causes were. I've put a great deal into the setup on my Z, and I don't want to trash it due to bad fuel mapping from the ECU, since fuel systems are all brand new on the car it would leave the ECU as the cause.

 

Do you work for JWT, or just really like their stuff? Because you sure have a hard-on for defending them, since all you saw in my question was me bad mouthing them. I could have a bad apple, but when I asked JWT I was immediatly shot down, so I posted on the forum to see if anyone else also had customer service issues with JWT.

 

And SleeperZ was correct, I should be between 13-12 AFR for max power. Russ Charlton's vg30e N/A build has a similar set up to mine, and he makes most of his power between 13-12 AFR. Understandably not all engines are the same, but with further research I found that the vg30e's run better slightly lean N/A, but not as high as 15.7!

Edited by BlueZ31
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Do you work for JWT, or just really like their stuff? Because you sure have a hard-on for defending them, since all you saw in my question was me bad mouthing them. I could have a bad apple, but when I asked JWT I was immediatly shot down, so I posted on the forum to see if anyone else also had customer service issues with JWT.

 

 

 

from the post before -

 

 

"Im half tempted to go to a local junkyard and replace this JWT crap"

 

 

I was trying to clarify what you were asking. I am interested in what's out there in engine management so anything I can learn about the various companies is valuable to me. But if you could step back and be a little more objective, you would see that you just made my point for me in your last post. Your issue is with the one guy you talked to at JWT, not their products.

 

Just trying to help you focus on the real issue...

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"Im half tempted to go to a local junkyard and replace this JWT crap"

 

By JWT crap I meant THE ECU which is not functioning as I believe it should, as do many other z31 owners I've spoken to.

 

"so I posted on the forum to see if anyone else also had customer service issues with JWT".

 

A post can have more than two questions, as it can have more than one answer. My concerns were mainly that the car was running very lean, what the ideal AFR would be, AND to see if anyone else on the forum has had customer service difficulties with JWT or issues with their ECU's as well.

 

I am focused on the real issue, that being my car not running at its full potential, and the potential of the lean situation causing piston-face and other wear issues with prolonged use. I contacted JWT via email,and included dyno graphs as well ( I dont know how to post JPEG's to the forum yet, not PC savy), but haven't recieved a response as of yet. No junkyards in my area have N/A ecu's available, and the only ones I have are CAL turbo units I scrounged while stationed in California, in preparation for a future turbo swap. I also did another AFR test, using a Innovate unit in a spare bung in my headers, and confirmed that the AFR is very lean under load/WOT, proving that the dyno shop was correct in their findings. With further research online I was able to eventually find where my engine should be at AFR-wise for peak performance, but not than anyone has had issues with N/A vg30e ECU's before.

 

The best I can say is that, with so very VERY few N/A vg30e guys out there, and even less using a JWT ecu, that some issues could occur with the product since I'm sure JWT has quite a lot going on in their shop, N/A vg30e programming is probably the least of their concerns.

 

I am interested in what's out there in engine management so anything I can learn about the various companies is valuable to me.

 

You could take my current predicament as a warning on JWT

OR go off another experience

Project tuner mag were the ones that inspired me to go JWT, since I'm not savy with Nistune or A'pexi. In one issue they had a N/A SR20 in a early 90's Sentra SE-R that picked up 20+hp with a JWT ecu and CAI alone! They had good luck with JWT, but then again they're a magazine so I'm sure that JWT would do their best on products advertised to the public. Most people have had excellent service from them if youre interested in JWT in the future, which is why the poor performance of my ECU and handling of my issue suprised me greatly.

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Was the engine running properly and putting down corret numbers prior to the JWT install? Maybe there is an underlying fault somewhere that was missed? I've done this a few times when I'm in a hurry and almost melted down a motor or two. I always check my setup before I add tuning now, its not cool when an injector didn't seat correctly/manifold is screwed and is spraying the wall or you forget about the coolant line on the back of the S13 SR...

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Not exactly an answer to your question, but you are pretty much at the limit of those 180cc injectors, assuming you're running 3 bar fuel pressure. Having said that, you're near the POWER limit of those injectors, which would not be an issue under 4100RPM.

 

As a dyno owner/operator/tuner guy who uses tailpipe WBO2 probes most of the time, I can tell you it makes basically no difference where the probe is once there is significant flow out the exhaust. On most cars, even at idle, you can get correct readings. Though if you have a 5 inch exhaust tip or something of the sort, expect false lean readings until the flow is there.

 

Since you also tried another location in the header and got the same results (BTW why didn't the dyno shop use that bung for the testing?) the only thing I can think of would be an exhaust leak at the header that introduces fresh air and therefore more oxygen.

 

So, assuming the car is leak-free, mechanically and electrically sound (and that the Innovate WB you used in the header was correctly calibrated), then IMO there really isn't anything other than the ECU to blame!

 

With a real 15.7:1 AFR at WOT, you're probably leaving a lot on the table. You should probably feel it's missing something.

 

HTH.

Edited by bradyzq
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Thats exactly how I've been feeling! Finally someone READ my question and UNDERSTANDS what I'm trying to find out.

 

As far as exhaust leaks, it could be possible with the Pacesetter headers I'm running, BUT when I had the engine out I had all the tell-tale black soot marks at leak sites, and had them welded up nicely. I spoke with the same JWT tech again today, and gave him the same run-through as yesterday, and emailed him (again) the dyno results, to which he replied "Ill get a tech on it and get back to you" Hopefully sometime soon, so I can get things corrected and enjoy it before deploying this Dec.

 

The 160.6whp it's making seems healthy while driving, but it does feel as though I should be getting more, as far as throttle/engine response on the highway. Fuel economy has been excellent, probably due to the very lean AFR, but the engine feels like it wants more. Hopefully JWT can correct the issue, otherwise I may fall back to a stocker.

 

Another question...what year vg30e Maxima ECU's could I use, with the injector driver/02 sensor differences?

 

Oh and I should say the "JWT ECU upgrade program" not ECU, since I was sharply and repeatedly corrected by the tech over the phone when referring to the ECU as the cause.

Edited by BlueZ31
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I did do a plug inspection recently, I'll have to do it again (tommorrow if the weather clears). I'm running NGK v-power coppers, last time I did the inspection they had a light grayish tone. Hopefully JWT will get back to me tommorrow and I can get the situation worked through. I want to install my own wideband but theyre damn expensive! Thanks for the tip.

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  • 4 months later...

I did do a plug inspection recently, I'll have to do it again (tommorrow if the weather clears). I'm running NGK v-power coppers, last time I did the inspection they had a light grayish tone. Hopefully JWT will get back to me tommorrow and I can get the situation worked through. I want to install my own wideband but theyre damn expensive! Thanks for the tip.

 

Are the injectors in good shape?? have they been cleaned and flowed, dirty injectors can lose as much as 30% of the orginal flow rate..which could be causing your lean readings... By you last plug check you should not be lean, if so the plugs would be white with some possible blistering on the cermaric..

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  • 2 months later...

I just read a lot of this, but not all of it...I've PERSONALLY seen 165whp on stock NA injectors (180cc) with a stock NA ECU. Mods were intake, gutted plenum, header, 2.5" exhaust and advanced ignition timing...and thats it. With cams, head work, etc...you should probably get some turbo injectors (260cc) and Nistune a different ECU and tune it properly.

 

www.nistune.com

Edited by michaelp
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