Boost problem Help please !!!
 

Guys,

Please forgive me if this has already been posted by someone I have tried to find similar but no luck.

Anyways here goes, I have a 1993 RX7 Type R with Greddy SMIC, HKS Racing Suction kit, Blitz dump valve, 850cc injectors, Power FC and boost and oil temp gauges and Greddy Profec B (original one not spec2) boost controller.

I had my injectors done and a base map put on the car so I could drive it to where it was being mapped. That evening I fitted the HKS RS kit and the boost controller. The next day I drove off boost to get the mapping done about 80 miles away.

While the mapping was being done we noticed a boost problem, we believed it to be a loose air induction hose etc so it was part mapped and I drove it home again off boost.

The problem is that if I accelerate hard from 3000ish revs into the 2nd turbo the car boosts at 0.8 then if I let off and put my foot back on the car makes 0.4 bar and when letting off again get a weird high pitched noise like trapped air rushing out (like back pressure sort of noise).

Been over the car with a fine tooth comb at the induction side. Replaced a couple of split hoses but no joy, made sure all the pipes are done up tightly/not split/cracked etc.

Now I cant honestly say if the problem was after I had the injectors done (I didnt go on boost after this was done) or after I did the boost controller and induction.

When fiddling with the boost controller there are 3 knobs, 1 for balance, 1 for low and 1 for high, I have played with the balance but this doesnt seem to make a difference. If I set the car to high boost and play with that knob even if I set it to lowest the car will still make 0.8 boost when accelerating hard. If I crank it up the car makes the same amount of boost. Forgive me for being dumb but I'd have expected that to not be the case if I'd set the knob to the lowest setting.

Getting really frustrated with the car at the moment, when its on boost at 0.8 its very quick and I love it, when its playing up I am contemplating selling it.

Dont want to do this at all as I love the RX and its been great since then until I modded it lol

So what would you guys recommend looking at next ? Could it be a faulty boost controller ? Or is it likely to be one of the hoses in the rats nest as this was taken out when the injectors were done ?

Please help,

Gareth

p.s. sorry for the long post.

Anyone ?

Been out in it now and there is a barking sort of noise coming from the airpump pulley area, it seems to spin and then stop until the revs go low and then it clicks in again.

Is this normal ?

Thanks
Gareth