hello people-would really appreciate some help on this one!! i have an `87 s2 that holds back and surges under med-hard accelaration.mainly when the engine is warmed up.here is a list of what i have changed/eliminated:fuel pump,fuel filter,injector seals,valve stem seals,plugs,leads,cap,rotor,have had ignition system checked by a garage,advance/retard pipe from ecu-manifold.also the car never seems to come up to temp according to the `norm` on the gauge.the needle is always below this section-even after extended or hard driving.(the air coming from the vents can be v hot!!!) any ideas and questions welcome.

cheers guys

 

Mine hesitates slightly 'under load' but I need to get it on the rollers to make sure everything is ok, I suggest you do the same made, sounds like u have eliminated many possabilitys, the RR will tell more. Regarding getting upto temps, do you have the thermostat in? Does your fan kick in ? You should find a period of even short driving and coming to a halt it should take a few minutes before the guage climbs to just over half and the fan cut in and bring it back down to ust above the 1/4 mark if all is well. P.S ven't will always be hot

 

as adam said for the temp really!!

as for the surging agree again get it to a tuner.
sounds like its underfueling in the midrange (as mine is) hence the surging.
do us a favour, take it for a drive and when its surging put your foot hard to the floor.....does that eliminate it?

(best in 3rd, from 2k RPM floor it....is there any surging like there normally would?)
if there is then its a different problem, if not thats your answer!

 

i was thinking about going for a rolling road session.also my temp gauge never reaches half-way!!it usually floats between a qtr and the solid white section at the bottom of the range!the fan can also be running at these low temps.poss temp sensor fault???

 

the car will surge even under full load.also i did forget to mention that sometimes the car will run with none of the problems and really fly but the majority of the time the hesitation can reall be felt??any other ideas?


cheers for the input btw

 

sure it aint hittin the boost limit? Just a thought? It chipped i take it?

 

no mate it aint chipped but it def isnt hitting the boost limit.it does in 5th in cold weather but thats all.

 

Get it to a reputable tuner mate, make sure all is well

 

still sounds to me like all it needs is a tune.
possibly one of your boost hoses is collapsing but unlikely from the symptons.

temp gauge sounds fine to me

 

Sounds like a fuelling prob m8.

 

mine also has a surge like its holding back in 3rd through to fith but when ya floor it from say second then go through the gears it seems fine dunno goto get mine checked?

 

Possibly over boosting one time i found that if i booted it in 3,4, and 5th gear inbetween 2500-4000 rpm it would hold back i then took it to SCC performance in ST albans in Hertfordshire and they told me it was over boosting on the standard chip so it must have been runnin about 12-13 psi when it should have been running about 8psi iwould surgess you take it to an RS specialist and get it set up properly like the others have said. GOOD LUCK BRUV