Fiesta ST 180, Low Boost, No Vacuum
Hi All,
Hopefully their are a few car nuts in the crowd, having a few issues with my Fiesta MR230 with low boost, normally she should read -8 / 10 psi on idle and + 24psi on full throttle, i'm currently getting + 1 psi on idle and + 12 psi maximum on full throttle, iv'e checked all the pipes and clamps from and to the turbo, iv'e checked the diverter valve and inlet pipes with no luck.
Any suggestions welcome.
Thanks Mike
Re: Fiesta ST 180, Low Boost, No Vacuum
Have you tried dish soap on the joints at full throttle? It does sound like a leak somewhere on the inlet side - maybe around the intercooler, if you have one (since they're exposed to more road debris that the rest of the inlet system)
Re: Fiesta ST 180, Low Boost, No Vacuum
Ever figured it out where is the leak? Could one of the hose clamp. Our previous neighbor had the same problem and the leak was on host clamp on connection 4, needed to remove fascia to access it. Our old tractor even had the same issue which as solved by Fass fuel pump and even gave 1mpg improvement.
Re: Fiesta ST 180, Low Boost, No Vacuum
Have you tested the gauge to see if it is reading correctly? Are there any other symptoms of low boost pressure? (While noting that the thread is a month old... :))
Re: Fiesta ST 180, Low Boost, No Vacuum
An impromptu leafblower impression is a sure bet for a manifold leak
Re: Fiesta ST 180, Low Boost, No Vacuum
Thinking about this more, I think you're right about the sensor playing up - a petrol with that kind of leak will not idle. If that much air is getting into the engine at idle and the ECU is still giving the usual fuel amount then it won't run; it'll be ridiculously lean and the engine will stall at anything other than full throttle. If the ECU is adjusting the fuel for the air getting in then it won't idle - the engine will run flat out all the time. Diesels can take being run without a solid connection between the turbo and valves, but a petrol can't. I was wrong about the dish soap, an intake system has a flow rate far too high for that to show a meaningful leak
Re: Fiesta ST 180, Low Boost, No Vacuum
Hey Chaps,
Finally did trace this down, My Mtune Handset was reading incorrectly lol, tested it using a Bluetooth OBD port reader and torque app and and correctly holding -10hg on idle and 23-24psi on full boost.
Rather anoyying really as spent quite a bit of time under the car checking and double checking all the clamps removed some parts i had even fitted to see if they was the cause as well which iv'e now got to refit.
Re: Fiesta ST 180, Low Boost, No Vacuum