erratic power delivery.
Turbo Mini Forums

Hi, im after some help..

As some of you will know my car is now road legal, great, however actually driving it is a right pain.

Firstly it starts and ticks over fine – and all in all first gear isn’t too bad, however the power delivery can be a bit erratic and this is where the problem begins.

When I shift up to second (and any subsequent gear) it is very unpredictable, sometimes when accelerating I will get nothing at all, no increase in revs and no go resulting in the car stalling and me having to crank it again.

If I do get revs when I accelerate then the power delivery is very erratic and im hopping down the road.

This is my first few runs in a turbo mini, any ideas what I should be checking first?

Could it be the timing (megajolt) or should I be looking for the problem somewhere else??

Cheers, Mark.

Mark is the same in all driving situations ? ie driving slowly, cruising or nailing it ?
Does it miss-fire or just cut out and then run on all cylinders again ?

"So wat we gonna do tonight Brain?"
"Same thing we do evernight Pinky!"
"Try to take over the world!"

a little worse when giving it the beans.. but its also like it doesn’t want to cruse, so i suppose it all driving situations.

no misfire and its running on all 4.

has it been set-up?

do you have a wideband on it? Whats the mixture like?

not set up yet.. first run really. Thought i should be able to get it somewhere close before the rolling road.

no wideband but i have the option to fit a mates if i weld a boss in..

to be honest the more i think about it the more it feels like fuelling / a/f ratio..

the running out of puff can sometimes be a blocked or restrictive fuel filter, i had it before, ran fine on the driveway, took it down the road and the carb ran out of fuel, crank it and it would run for a bit and do the same.

same goes if you mod a standard tank and leave the strainer in the bottom

Wouldnt be related to dashpot oil would it?

Its suprising how many issues it causes.

give us a shout if you get stuck tomorrow dude, don't think i've got much planned apart from washing the car if its not raining.

does it do the same from cold and heated, you could have issue with float bowl heated by the turbo. it does a bit like this.

mixture too lean or rich ?

search for the T peice trick which turbo dave wrote

i had this, loose earth strap!

strange but true!

had another issue on a different car, goosed pump!

if you run a non mpi or spi tank and also a fuel return to the tank then you HAVE to remove the strainer on the pick up pipe inside the tank.

to remove it tape a broken hacksaw blade to a stick and stab the strainer through the filler neck ( spearing the mesh is as good as removing the hole thing)

problem fixed!

Me and nick removed the strainer on the pick up pipe inside the tank and then noticed a bit of a school boy error..

it pains me to say it but i had wired the fuel pump up wrong.

Its on a relay connected to oil pressure, however i had the pump going 'off' when we had oil pressure not 'on'. :$

so i would only ever have the fuel that was in the lines.. then it would stall and the pump would come back on etc.

anyway the car is now running ok, still some tuning required as suspected but apart from that its all good.


thanks for all your help.

Edited by MarkGTT on 14th Jun, 2009.

don't forget to stick the fuel filter back in dude!