Recently got this tune out here in vegas from some guys who usually dont tune vq's but are aem certified and assured me that they could tune an aem/fic. my car runs fine and boosts well up to about 5500 to 6000 rpms before it hesitates, bogs, or misfires. Im new to FI so im not sure how to tell the difference. this tune cost me about 440 with about 6 runs on the dyno. final run they felt the tune was good. with that said, id like to hear opinions from some of the experienced guys. i have a rev up engine 06, turbonetics, 6psi. im not worry about the horsepower. i wanted conservative so with 330 hp, i wouldnt have been disappointed with the power at this point in time. i just wanted my car to run well. Im no expert so I wont make any judgments at this time. im also going to post this on the aem website and see if i can get any tuners input on this as well. Thanks

 

looks like the tune is probably ok, but you have something mechanically wrong. maybe spark blowout, weak coil....

are you using 1 step colder plugs? yo might wanna try closing the gap..

 

Ya i used one step colder copper v power. They were all gapped to 1.1 factory spec, i believe. what would you suggest i should gap it to? I do throw random misfire codes as well. The tuner said that this is sometimes normal in FI cars.

 

That curve is horrible. The AF looks good, but you definately have some kind of ignition problem. As to the cause of that, it would take some troubleshooting to determine. Did they install the FIC as well? Perhaps a wiring issue, loose connection.

Was the car running on some other system prior to this new tune?

 

You need to regap that to about .8 (.032), 1.1 is stock .043 gap). I have had my plugs in for about 10k at that gap, and decided to check them recently. They look just perfect.

 

I'd gap coopers to about .029" but if these are brand new plugs, I wouldn't expect spark blow out at just 6psi boost pressure.

 

No, the car was basically stock. I had a spacer in there but took it out due to some boost leak. I purchased the harness from boomslang so the wiring should be fine. As far as i can tell, the piggy back is working fine. Its connected to a wideband as well, when i open up the guage screen in the tuning program, everything is in working order. reads afr, boost, rpms and everything. Ya, i wish i did have someone out here to trouble shoot my car. They didnt seem too interested in doing it themselves. either due to inexperience with vq's or the fact that import races are in town next month and they are working on their own cars. I've read alot of threads on this forum and know that you (Sharif) are very experienced and have been in the game for a long time. Do you agree with straightdum as well? I can try to close the gap and see if it help. i have my timing maps and o2 maps saved on my computer if that would help anybody. the tuners were also suggesting that it could be my o2 sensors reading rich afrs causing my car to misfire, but I dont see why that would be an issue with my car specifically. Id also like to add that I purchased the kit with no cat. The farther two o2 bungs are extended already. another interesting fact is that my car will rev to redline when i slowly accelerate. but if i floor it, it bogs/hesitates/misfires at 5500-6000.

 

Your o2 sensors don't do anything at WOT... so that's not your problem. A/F looks fine too.

If I could call it how I see it, your timing map needs alot of work. To aggressive down low and not enough up top.

Whenever you see higher TQ than HP on a VQ (especially rev up) without breathing issues (at 6psi that turbo isn't even trying), the tune is questionable or there are serious mech. issues.

 

i want to add also that i appreciate the responses! I need help and I have nowhere to go here in Vegas. I can only hope to troubleshoot this and fix it on my own or tell the shop exactly whats wrong so that they can fix it.

 

Post up the screen shots of the fuel and timing maps.

And yes, it never hurt to pull the plugs and reset those gaps.

 

maps and setup

 

Dont mind tabs on the bottom. Wife looking for jewlry! i closed the tiffanys tab after i uploaded images.

 

Who did you use in vegas? Was it Mike Angel of factor X? I have tried a few individuals in vegas back in the day for tuning and i trust no one. I do all of my own work except tuning. All of my tuning in done by Sam at GTM.

 

Welcome to Vegas! The land of "do it yourself" or "take it to Intense."



WTF is Force Fed Racing???

 

first i went to trevtec cause i hear that hes good with nissans but he didnt have too much experience with vq's. he custom made my uppipe and did a "base tune" which was pretty much reflashing the piggyback. Which i could have done if i had read the aem website on my own. that "base tune" was 180 or something. then i went to forcefed racing. they have a dyno there. seemed like nice guys and i thought they knew what they were doing. well see what others have to say about my maps and tune. noone seems interested in trying to tune my car. are vqs complicated or something? im not even going for big hp right now. didnt really think it would be that hard to tune my car. Ive called gt motorsports before. but they always say theyll call me back, and never do when i wanted someone to install my kit. I wasnt trying to be a cheapo or anything and i understand it cost money to get your car running right. but i dont seem to be getting anywhere at this point in time.

 

hehe nice, got a few posts from vegas guys in less than an hour. i been looking for forums for vegas g's or 350s with no luck to inquire about shops. guess i found my answer without even asking!

 

i was optimistic about force fed because they are aem certified..

 

Where are they located?
Never heard of them before.
BTW i like GTM but i consider them nissan snob's. If your not dropping big money with them they don't want to be bothered with you due to they are very busy as it is. The big thing for them now is the 370 z's and GTR's. The 350z is old school now.

 

by the orleans in between the strip club and the whorehouse on arville. literally. And for those who arent from vegas, Im not joking

 

I think I found the issue. The MAF clamp needs to be set well below 5V. He has it set at 4.95V. You need to set it to 4.85V or slightly less than that. Your ECU is freaking out when it seems the overvoltage and causes the cuts and misfires...seen in many times before back in the eManage days. Keep in mind this will change the tune slightly so it needs to be verified on the dyno.

I also noticed he is using MAF as the load source for timing, but MAP as load source for fuel. Although this isnt the cause of the misfire, it's not technically the correct way to setup the tables. The engine will be happier if it's using a scaler that isn't maxed out all the time, as it will be if using MAF as the load source.

Politely mention these things to your tuner, and hopefully he'll adjust and retune for you. The misfire can be troubleshot before even going on the dyno.