Erratic 2nd turbo

[Andyp]

Elo,

Just been out in the Rex for the 1st time over xmas, so its been sitting in the drive for about 2 weeks, usually used every day...

Anyway the spark plugs are due for a change which im gonna do..

Car was very smooth on the 1st turbo but it was spiking in 2nd... kinda like a car would when its got fudged HT leads... jumpy boosty...

My question is, is the 2nd turbo on a seperate setup? More than certain its the spark plugs as i\'ve had exactly the same kinda jumpyness in my last car, but thought they were pretty much running all the time?

Any thoughts?

Much thanks!

[iaint]

It has a separate set of vacuum hoses and solenoids for controlling it\'s operation.  Boost spikes seem to be caused by either a poorly solenoid or a leak in the tubing.  Easy to fix if you know where to look...  I took mine to a specialist to get this kind of problem sorted out - too complex for my little brain!

Iain

[Fishy]

Andy, what modifications does the car have?

Dan

[Andyp]

cheers Iain, think I\'ll check the hoses over if it keeps doing it... as I say think it\'s mostly *hopefully* due to sitting there for two weeks, think its needs a good run...

Dan, just kakimoto r racing exhaust and HKS induction, nothing that elaborate

[Fishy]

OK, if you\'re running a centre de-cat and back box with an induction kit, this could give you over boost.

If you have a FULL exhaust system fitted, get yourself an Apexi or something and get it mapped to sort out the fuelling. You might save yourself an early rebuild.

Dan

[20B_boy]

Originally posted by Andyp
Car was very smooth on the 1st turbo but it was spiking in 2nd...

Describe EXACTLY what you mean by spiking Andy - do you have a boost guage?? Do mean boost spike as in its overboosting like Danny says? or it is just erratic boost i.e. probably a control system problem?

[Andyp]

sorry probably poor choice of words there. No gauge at the mo, should arrive tomorrow hopefully!

The best way I can describe is as I say its like a screwed HT lead. It boosts but kinda dies in power then tries again..does get there, but its a very lumpy type acceleration...

Only happened today, was fine before.. as I say been sitting still for two weeks...

Been out to check the hoses round the alternator with my power torch and checked the black plastic jobby and checked the hoses near the sparkplugs... all seem well, though if it does it again tomorrow on the way to work, i\'ll have to re-look at it

[Davegtt]

My moneys on perished vacuum hoses on the second turbo boost circuit.  It might clear after using the car again.  If it was electrical it would probably do it more at lower revs due to the engine load.

Dave

[Andyp]

think you\'re right dude, it was fine again this morning, boosted it about 5 times on the way to work into the 2nd turbo... worked fine

how odd.. if it was perished, would it work on and off then?

cheers

[iaint]

When this used to happen to my FD it was when everything got warm - made the perished hoses very flexible and they leaked.

Beginning of journies would be fine - the end would have no 2nd turbo.

Iain

[20B_boy]

Indeedy, see what she\'s like when properly warmed up mate...

[nikp]

I get the same problem, which I haven\'t got round to sorting yet. Boost is fine when still relatively cold, but once it\'s been used for a bit, 2nd turbo is all over the place. I\'m confident it\'s down to vacuum pipes or hoses getting warm and leaking.

[Davegtt]

Just buy your self a nice reel of silicon hose and go about swapping it all out, be a nice 30 mins work

he he he

[Andyp]

hmm it was both fine on the way to work and on the way back

Not doing it at all now. I think if anything it wasn\'t warmed up enough the other night, was showing my mate the car and booted it before the time I usually would, so dunno if that caused it..

I\'ll keep an eye on it for the time being, see if it does it again

thanks for the help anyway

[tom]

i know where your coming from! i gave mine a bit of welly the other day when the water temp was warm but the oil was not up to temp(naughty). but the second turbo seemed to be very up and down in boost!  it was definatly due tempriture! learned by my mistake.