weird accleration/boost problem

[Slim]

right.. not sure how im going to describe this problem,, but il try my best.

Bascially,, My car recently broke. I have recently got it back up and running,, after my acceleration stayed down a bit too long (over revved) while changing/missing gear tryin to get it into second unsuccessfully then breaking a valve. Thats all fixed now.

Except,, i thought it over revved because the acceleration cable may have been sticky somewhere or the carb. Since rebuilding it again, there is no problem with a stick accelrator cable or throttle. its all free and fine.

Heres the weird bit. If i accelerate hard(foot down) specially in first gear, as the boost kicks in and gets to high revs, if i were to let go of the accelerator, the car still accelerates for about nearly a second. As if there is more boost in the system for some reason. :scratch:

can it have anything to do with an oversized air filter pipe compared to the rest of the boost circuit???

[HULK]

Sounds like a sticking accelerator pump on the carb to me, won't have anything to do with ya air filter or pipe

[Slim]

Sounds like a sticking accelerator pump on the carb to me, won't have anything to do with ya air filter or pipe


???

but if i test it when the car is on.. it does seem as if it sticks at all.. what do you suggest i do?.. the carb was off too before n i thought it seemed ok :scratch: but then im no good at carbs :(

[HULK]

The accelerator pump arm on the carb is underneath the carb and has a spring over it. Give that a blast with wd40 whilst pushing it in and out with ya accelerator cable. Do it twice.

Take car for a drive then report back

[Slim]

keeping the carb on the car right? sorry :crap:

[HULK]

keeping the carb on the car right? sorry :crap:

Yes. Move the accelerator cable in the engine bay whilst your stood at the drivers side. you will see the little arm move in and out at the drivers side of the carb. Give it a good blast everywhere

[Slim]

k... il report back soon as

[Brigsy]

What is the idle set at? if its too high (over 1k) it will cause this.

[Slim]

well.. its not the acc pump... i js WD40 it and it didnt do anything.


What do you mean if its idle at over 1k it will do this.. My car has nearly always idled slightly over that and has'nt been over revving before..:scared:

it feels like there is air still in the system not burnt off yet or somthing... any other ideas anyone? :scratch:

could to long of actuator pipe cause this? (not that i think so)

ALSO... it feels as tho it only does this on boost,, not off boost...

[Tony Walker]

Its not air in the system because when you back off the throttle its the blade in the carb that restricts the flow so no amount of pressure or length of pipe before it matters. It does sound like something sticking and releasing slowly, perhaps your accelerator cable or the acc pump arm, my acc arm was slightly bent and jammed in the same way keeping the throttle open. Maybe a weak spring or a slightly tight mechanism on your throttle linkage, they do come loose too maybe try tightening the nuts securing the accelerator mechanism. Best bet is to get someone to press the accelerator while you watch the throttle open and close.

[Tony Walker]

If its idling slightly high too maybe you should check that the throttle is closing properly.

[Slim]

Its not air in the system because when you back off the throttle its the blade in the carb that restricts the flow so no amount of pressure or length of pipe before it matters. It does sound like something sticking and releasing slowly, perhaps your accelerator cable or the acc pump arm, my acc arm was slightly bent and jammed in the same way keeping the throttle open. Maybe a weak spring or a slightly tight mechanism on your throttle linkage, they do come loose too maybe try tightening the nuts securing the accelerator mechanism. Best bet is to get someone to press the accelerator while you watch the throttle open and close.

ive checked it myself.. (pressing the pedal down whilst looking to see if i get full throttle... and seeing how quick it goes back.. it goes back quickly as expected)

when i rev the car at idle its fine,, when i drive and put my foot down off boost its fine,,, just wen boost comes on (after 4k) then id let go but the pedal wont release or come back up straight away... but it will if its not on boost :scratch: not sure if anyone understands this...

[Sparkie]

i think your throttle cable linkage needs adjusting. do you have the little link cable set at the correct length?
shorten your carb spring too.

[Sparkie]

i think your throttle cable linkage needs adjusting. do you have the little link cable set at the correct length?
shorten your carb spring too.

[Slim]

i think your throttle cable linkage needs adjusting. do you have the little link cable set at the correct length?
shorten your carb spring too.

im pretty sure the spring is fine.. cos the bracket its on.. has been pushed further back so the spring has even more force... ive checked it.. and its strong and goes back into position fine.

cable linkage?? im not sure what this means... but what ive done so far is.... adjusted the accelerator cable near the carb, to make the pedal sit slightly lower now, then i have also adjustted that arm on the accelerator pump thing. I turned that gold thing on it so theres less of a gap when the thottle is fully open lol.. i have no clue how to explain that.

Then i took the carb top off to see if that circle thing shuts and opens fine,, and it does. :scratch:


Could it be anything to do with fueling? OR .. my exhuast housing on my turbo being chaged to a smaller machined out T2 .35 or somthin housing.. put on my t28.??

[Slim]

feck it.. i think im js gna get a rev limiter :cooter: