put foot down car seems to gag

[mbu10]

just taken car for a nice blast around
all seems well apart from a couple of times it started to gag when i wanted to accelrate quickly
any one got any ideas
thanks

[Big Al.]

Just to be the first, have you cleaned your STEPPER MOTOR?

[mbu10]

well would do but need a huge adjustable or spanner and do not have one that large going to have to aquire one monday

[Big Al.]

Try a pair of parrot grips! if it's not too tight you may save a purchase.

Size BTW is 32mm.

[GreenV8S]

You may find you can undo it by hand, I'd advise against using any gripping pliers as the body is quite fragile and they're expensive to replace. In any case the stepper motor should only affect the idle performance it shouldn't really affect the behaviour under power.

Try disconnecting the throttle pot. If it's working properly, disconnecting it will make the flat spot *much* worse. I suggest you reset the ECU afterwards by disconnecting it for thirty seconds, this will prevent the ECU from registering a fault from the missing throttle pot. Also if the ECU has gone into 'limp home' mode this will put it back into normal mode, if this is what is causing the problem then you may find the symptoms go away briefly when you do this.

[mbu10]

well just cleaned the mass air sensor with some spray alcohol and removed and reset the ECU
will see what is happening when i take out tonight

[Nuggs]

Might also be worth checking the HT leads and dizzy - I had a slight misfire when planting the throttle and some shiny new Magnecors sorted it...

[Ballistic Banana]

I had ht lead that was shorting out on the manfold and causing a similar gagging promblem. not saying yours is but worth checking the leads for condition etc.