Throttle response Questions.

[Tricky-Ricky]

I had a look at two 350z today, both engines sounded fairly good, but on one the throttle response was very slow and the first time i planted it, there seemed to be a slight flat spot around the 4-450K mark any ideas?

 

Details, the sluggish one had a few mods, and very well looked after, engine mods, induction kit, full exhaust with race cats, and a plenum spacer Couldn't tell any signs of an air leak!

 

Yet the other 350Z bog std with more miles had a very good throttle response!

[350 Russ]

the mods were prob bringing power down. to get the best results out of the engine mods like an exhaust or a plenum spacer you will need a remap

[Tricky-Ricky]

Are the mods likely to make that much difference to the throttle response? i wouldn't have thought that it should have made that much difference, the throttle response was very slow compared to the std Z i tried?

It felt OK once it got going?

[scottsoulby]

might have suffered from a bogging issue from the induction kit, like said, once remapped, it will be fine and probably better than the standard

[Chris`I]

I'm pretty sure Beavis told me when he removed his pop charger his car felt to respond better and pull a bit better too. Too many breathing mods (intake, plenum, cats and exhaust) without a remap will lose you low down torque and I guess could cause fueling problems which could manifest as a flat spot, although I've never seen evidence of that on any dyno days we've had or plots I've seen.

[Tricky-Ricky]

It was a nice example, best i have seen so far, but that was a little worrying, wanted to get some opinions so i could judge how to proceed.

[Tricky-Ricky]

Read something about throttle reset when battery has been removed, could this be a reason for the bad throttle response?

[rtbiscuit]

Read something about throttle reset when battery has been removed, could this be a reason for the bad throttle response?

 

yes there is a combo to do a throttle position reset

[Husky]

http://www.technosquareinc.com/350reset.htm

[3FIDDYZ]

One reason may be with regards to how its been driven before you drove it. As Mark @ Abbey has said, its takes a few runs for the car to show its true colours on the dyno... perhaps its the same on the road.

[Tricky-Ricky]

One reason may be with regards to how its been driven before you drove it. As Mark @ Abbey has said, its takes a few runs for the car to show its true colours on the dyno... perhaps its the same on the road.

 

I think maybe the two occasions i took it to 100 leptons may preclude that, but i may be wrong

[matth76]

Do you know what brand of exhaust he had? Because that can make a bit of a difference (if for example it was a 'true dual' system), even more so if it has not had a remap. I wouldn't have thought the induction kit would cause the feeling you felt as you mentioned the car was going approx 4000 revs and by that speed you would definitely be getting enough cold air in unless you noticed the flat spot when accelerating from a standstill as an induction kit can suffer from heat soak - however if the car was already moving and you then accelerated you shouldn't have had a flat spot. Do you know approx what mph/gear you were in? It could of course be none of the modifications causing the issue but something else causing it (faulty maf sensor, plugs on way out etc). If in doubt move to the next car. You shouldn't have any doubts before spending out on your car.

[Dblock]

It could just need a reset. When i drove the 350z when the battery kept dieing it was a little jerky as in there wasnt much accuracy to the pedal. But after a few days it will get used to me or maybe i get used to it hmm?