Accelerator/ fuel lag off idle

[valentine66]

Does anyone know how to cure/fix the accelerator lag that happens when I tap the throttle. I push the accelerator and theres a short delay from idle to higher RPM's. Ive also noticed a considerable lag from when I hold the revs around 2000 and suddenly let off the pedal. Once im up to operating speed, everything runs perfect.No misses, backfire, stumble. when I start off from idle, its slow to respond.Is this normal?
2008 350z, 6 speed M/T

[dasoupdude]

Your clutch is slipping like Mario on a Banana peel, how many miles are on it?

Try shifting your to 6th and flooring it at about 50, if the revs jump and you feel another lag in accelerating then your clutch needs replacing.

Recommend a jwt stage 1 clutch and flywheel kit, its the closest feel to oem with more performance without breaking the bank.

[valentine66]

I should mention that this issue happens in neutral, and only when I throttle up or down. Car only has 33K miles and has been well taken care of ( no racing, drifting etc.)
Any electronic mods to make the accel. pedal more responsive.

[BusyBadger]

The small amount of lag in the Z's drive by wire throttle control isn't really as bad as most peopel think (try riding in a VW Jetta sometime...ugh).

Anyway, there are a a couple of things that you can do to make your car a bit more responsive.

Electronics: Two main choices come to mind: Sprint Booster and Blitz Power Throttle Controller. If it's me I'd go with the later...Blitz has been making go fast parts for Japanese vehicles for ages, and I have no clue what Sprint Booster's track record is. You might also be able to get something from an UpRev or TechnoSquare tune, but you'd need to check with them.

Mechanical: LIGHT. WEIGHT. FLYWHEEL. It's the best driveability mod I made to my Z...the Z's dual mass stock flywheel weighs a ton and takes a lot of power to get it rotating, I went with Exedy and I think Soup went with Jim Wolf, I'm pretty sure he's as happy with his choice as I am with mine. It really makes the tach rev like it should have from the factory, you will hear some flywheel chatter and get the occasional comment about, "I think something is wrong with your car", but those in the know just look and nod their approval.

Welcome to NICO!

[valentine66]

Thanks BB.and Soup,
This is my first Z and im still feeling out all the " personality quirks".
Thanks again.

[emhmotorsports]

From what you described, I believe your problem is electronic related. Long story short, all OEMs do some creative filtering between the pedal and the throttle blade on ETC systems, some much much more than others. I think Nissan generally does a good job, but others are horrendous (GM, VW). They're forced to pull these shenanigans because it seems a large majority of people that buy cars will complain about any stupid little thing. They filter tip-in to keep people from scaring themselves when the car lurches forward suddenly, and they filter tip-out to assist in gear changes in M/Ts. I know, I know, but the answer is "yes they have to do this even on purpose-built sports cars." Very sad.

To really fix the problem you can try one of the gizmos that BB mentioned. I have an Exedy flywheel, and I found it helped a little on light tip-in response and just a touch on tip-out. Personally, I do find the additional noise of the Exedy (non dual-mass flywheels in general) right at the limit of tolerable, so be prepared if you go this route.

I have converted my 350Z to a true linear ETC system (through means I cannot divulge) and it is truly something awesome. I have to keep a spare pair of shorts in the car now for when I wet myself in delight. The Exedy has a much bigger impact now too and now it revs like a FIA Touring Car. Granted, I am part of the 0.01% of car owners that enjoy cars which immediately and aggressively respond to my commands.

[valentine66]

EMH, you cant leave me hanging. Whats your secret???? Im not looking to blow the wheels off, but that delay/ lag crap is driving me nuts!!!!Im tired of lurching off the line like a 15 year old learning to drive a stick..Any thoughts on tuners like Edge, Hypertech, Bullydog?
Ive read on other sites the pros and cons of Blitz and Sprint. Ask 10 people, get 10 opinions.Seems every "Tuner" shop is all too eager to sell me a "Performance" chip. Before I drop $400 bucks, I'd like to get some real answers from real users.Seems the more I look, the more find(junk and legit).

Thanks

[emhmotorsports]

Sorry for the delay - I was in Daytona for the 24. I don't really want to say much about my solution because it's still in development. But I can just tell you that if you can get the throttle blade to move with the pedal (as they did with old cable systems), the Z becomes a different car.

I don't have much experience with aftermarket tuning systems, because us engineers generally try to avoid them. In order to get the big power numbers they need to sell them, these companies end up taking out a lot of safety/protection features. I've even experienced some higher end systems cause slight driveability issues. A friend of a friend works at Bullydog - they are definitely knowledgable about diesels, I don't know about their gasoline stuff. I recently drove a BMW 335i with a COBB tuner and this car was a beast! It would easily tear my 350Z to pieces in a drag race. It seemed to drive fine for the little I hooned around in it. Each person is looking for different things, so all I can recommend is to find a system you think you will like and that you can re-sell if you don't. Sorry I can't be of much more help...

[BusyBadger]

I recently drove a BMW 335i with a COBB tuner and this car was a beast! It would easily tear my 350Z to pieces in a drag race.

The 3i is a factory tc'ed V6, be a shame if one sporting a Cobb AP didn't chew up a Z. I was on the fence for a long time about getting a Cobb and since their support dropped for non-tc'ed cars I'm kind of glad I didn't. I'm sure that in the end I'll go with UpRev, if I don't go full standalone (no reason I need to really).

Line that 3 up against an Evo or an Sti running a Cobb and see what happens.

[valentine66]

Thanks guys, appreciate all the feedback

[jerryd1987]

the two things that where recommended both the blitz and the sprint do not actually effect throttle lag its actually exactly the same. theres a reason they are called boosters although amplifier would be a more accurate term, essentially it is just telling the ecu the throttle is pushed more then it is. so say you give 15% throttle it will tell the ecu you are giving it 20 or 21%, it gives the illusion that there is better throttle response but in actuality all it is doing is eliminating pedal resolution. not sure what emh's solution is but theres nothing you can do to eliminate the throttle lag of a electronic system, you might make it alot better but the only real solution is a cable TB however it will require a system like haltech to adjust tps voltage. i run my tps off of the pedal sensor and dont have anything running to the pedal sensor input on the haltech and my throttle response is amazing, nothing you can do with the electronic throttle to match it, although you can fine tune it by reducing or increasing cable slop. only thing is you would have to come up with some way for idle air control, i dont run it because hawaii is a pretty standard temp year round and even when i leave im not gona be running this thing in the cold it makes too much power.


cost for me was about $100 using a cheap ebay mustang throttle body(dont recommend) and lokar cable but i already had haltech.

cobbs support for the z market dropped because uprev just has a cheaper solution, if you dont intend to tune yourself there is no need to buy any cables