need a little help

matty0785

just bought another 2.2 astra coupe with a semi stripped engine im currently got it back together and running but it has really bad surging under load.

i have notice that the vacuum line that comes from the side of the inlet manifold there are 2 nipples one of them is blanked one isnt question is where is this meant to got to

new plugs
new chains
egr blanked
throttle body cleaned
cts sensor reading correctly on diagnostics

evocarlos

the little ones are both meant to be blanked normally
the bigger one goes to the vac pipe for the brake servo
the pipe from the fuel pressure regulator goes to the inlet pipe just before the T/B

matty0785

this one circled in red

the one with the white rubber is blanked the one circled had a cut piece of pipe attached and my fpr line is already onto the intake pipe

evocarlos

vec b or astra g ?

astra blanked both
vec heater valve ? @[deleted]

matty0785

astra g coupe

what would cause surging under load ?

i bought the car with a semi done engine swap and basically finished it inc full chain kits and a few other bits mentioned in first post

evocarlos

the vectra inlet has a bigger port for the brake servo vs the astra inlet

does it idle ok ?
could be an air leak on the inlet side hard to say tho

pottsey

evocarlos said:
vec b or astra g ?

astra blanked both
vec heater valve ? @[deleted]

on mine it had 1 in use ,I guess that was vec heater valve ,dunno never really knew where it went ,the other was spare until I took the pipe from the inlet pipe ,which is the fpr mod

matty0785

idles perfectly just surges under load right through the rev range

thought it was the cam chains causing the hesitation as they where a bit rattly/stretched hence replacements fitted