throttle body change

[wedgey]

help please

 

i have just changed my inlet manifold,extractors and throttle body

 

it had the 2.8l manifold 50ml throttle body and extractors ems stinger computer

new one is the naps manifold 65m ford throttle body and stewart wilkins extractors still have the ems stinger computer

 

my problem is that when i started the car after the change over

it revs to about 4500 revs and would not drop back the revs

 

tried the adjuster screw but did nothing to slow the revs down

do you think i should disconnect the computer and that would reset the computer

 

or is there something else i should do

 

thank you

robert

[Zeddophile]

I'd be guessing one or more of your sensors (probably mostly throttle position!) is giving a different output to previous... I highly doubt disconnecting the computer will reset it, you will probably have to reprogram it.

 

Perhaps try disconnecting the TPS, and see if it idles normally then... will probably run like a dog under drive conditions, but at least you'll be able to drive it to somewhere to get it retuned, unless you can retrofit the old TPS (assuming it makes a difference). However, I believe (from memory) L28 TPS's are of the ON/OFF type, while I imagine the ford item would be an potentiometer (varying voltage output from 0.5v to 5v, depending on throttle opening), which for precise tuning is probably a better setup. Obviously you'd want to check both with a multimeter before taking my word for it though!

 

Can't think of, off the top of my head, any other sensors which would make that much difference, but then again I've never seen a NAPS manifold....

 

The other possibility is maybe an intake manifold vacuum leak, but usually that would cause low and hunting idle.... If you have a map sensor, check that its correctly connected, and if its an airflow meter check that you haven't altered it in some way.

[sjcurtis]

With no effect at the adjuster screw, could also be bye-passing air somewhere else on the manifold or throttle body area.

 

Other position switch that could affect, is the resistor indicator in the airflow meter stuck open position. I also suspect the full throttle indicator stuck on.

 

good luck

 

Steve

[Mr Camouflage]

Hi Wedgey, I was just wondering why you changed to the napz manifold in the first place.

[wedgey]

hi

 

 

i was advised that the naps was a better inlet manifold for better air flow

and i was able to get it at a good price and the 65ml throttle body fits nicely to it

 

i am sending the car to the dyno next week hoping to a 10kw increase out of it

i had 90kw at the wheels when i first put the motor in with about 2000klm

on the clock just hoping to get the 100kw out of it

 

robert