T5's BOOST QUESTION

[mick1275]

Hi guys, who owns a HPT T5's do you get full boost through all gears 1st & 2nd i get 0 psi positive boost pressure, 3rd gear i get around 8psi DO I HAVE A PROBLEM HERE as ive heard c70 t5 boost from 3rd gear high pressure normal through 1&2 gears ?

[AlanG]

I find that boost pressure is lower in the bottom couple of gears. My opinion is that there is not enough time spent there for it to build as it just tears the tyres. 3rd upwards the guage is off the scale. HTH.

[p fandango]

you will be able to boost more higher up the gears because of the extra load, but 0psi really isn't right. I have heard of torque limiters on 1st but no boost is a first

[Knight Rider]

How do you know what boost readings your getting?? Have you added a gauge somewhere??

[mick1275]

C70 T5 COPUE 2.3L 2001 ME7.0 BOSCH ECU
1st gear holding at 3000rpm foot flat down to 6000rpm with 0 psi boost pressure straight into 2nd gear negative boost pressure unto 3500rpm vacuum at 20-25 inHg boost pressure then climbs upto 0 psi at 4500rpm keeping on the throttle to 6 grand into 3rd climbing between 3000-4000rpm i start to get positive boost pressure upto 8 psi @max rpm. Ive looked at the ECU NO fault codes stored ,also pipes ,hoses arnt a questions all brand new and secured with high pressure hydraulic hose clamps new actuator diafram no smoke from turbo or any in pipes I have also done a full vacuum system test by pressurising through the turbo i did find a minor leak @ the intercooler but repaired that.the only thinkl concerning me to this fault it the boost control selonoid situated side of air filter box but i would have thought a fault would have come up if malfuncting

[AlanG]

I would have thought the same buddy but the only way to rule it out is to try another. Pretty sure you're thinking this yourself. Keep us posted.

[wallace570]

my v reg 2000 c70 t5 (240bhp) gets 7-8 in 1st and 11psi in all the rest of the gears taking my foot of 23 on the vacume

[Dangerous Dave]

There's something wrong somewhere mate.

The BCS could be leaking but showing no code as the electrical side might be ok, be the mechanical parts might be worn/broken. If you've checked everything else, then it might be worth getting a spare and swapping it over.

Either that or there's a problem with your wastegate setting, or the actuator rod has come off. Have you checked that?

[bornagain]

I have a BCS off a s60 t5. Took it off for an upgraded one. I think it was working fine. Yours for £5 including p&p if you want it, or if your local to me you could always try it out.

[AlanG]

Is it the same unit as the original B5234T? Think mine is failing as I am getting a stutter on full boost........

[st1t5]

When my C70 T5 (ME7) was'nt boosting properly it was down to the actuator needing adjusting ... after that was done the car was fine.

The guy used a vacuum gun type thing to test the pressure in the actuator, its meant to go to 3psi, but was only going to 1.5psi, he adjusted the rod and all was fine after that.