This is more of a question about earthing I think. For a while (after I fitted an engine brace), I had an intermitent problem with hesitation whilst passing 4500rpm. Felt like it didn\'t want to go further and if I pushed it it would splutter and eventually kick in. The problem occured from cold mostly, once warm it seemed fine.
Having WI it also chucked a load of water through the system and generated a ton of white smoke when it happened. Anyway, it suggest MAP sensor, but once warm it was fine so I ruled that out.
Upon popping the bonnet and taking a closer inspection I noticed I had failed to connect the plenum ground wire to the firewall. Since then it seems to be 100% fine.
Can anyone confirm whether this would have been the cause of the hesitation? If so, is a ground wire upgrade kit worth considering?
Cheers
H
Yes it would explain the hesitation, however i am alittle more concerned about you pumping the car while cold ????
Let it warm up before you start blasting the car else there will be a bigger problem :(
Usually i dont give any boost until oil temp is up to 70oC, if you have a PFC but no oil temp reference then wait until water temp gets above 70oC
Thanks for the info.
I know what you\'re saying, I never boot it until a few mins after water hits 80+, give the oil a chance to warm up too (no oil temp yet) :)
First time it happened I just kept my foot at about 1/8th throttle in first and let the revs climb to 4500, the hesitation cut in and I just kept the throttle in the same position, at about 5500 it seems to get back to normal again. Water temp was about the 50 ish mark. Kept doing it for the next 10-15 mins or so after the car had warmed up, then was fine after that...
H
Earthing is a common cause of hesitation, as is injector transition point. Both can be cured fortunately!
what is injector transition point?
Its the point at which the secondary fuel injectors start phasing in with the primaries.
Stock Apexi settings (and I assume the stock ECU also) start phasing in these secondaries at around 40% primary injector duty - which is around 4000revs whilst cruising, lower when you are nailing it.
At the same time the secondaries cut in, the primary injectors hold back a bit to keep the fuel mixture correct.
Think of it as having two cups of water and two buckets of water, easy to create a drip with a cup, try it with a bucket!
Go larger secondaries (larger bucket) and it gets harder to get it set up smoothly.
You can control the phase in point, and also the rate of cut in of the secondary injectors, but it can take time with some cars to get right.
cheers max, :D
i liked the cup n bucket bit,lol