Boost lower than usual

[SamHendry]

My s3 has been mapped to run 24psi boost on hybrid and recently it decided to only boost to around 18psi.. Big drop in performance. Still pulls bit not like before, car showing no signs other than lack of boost displayed on gauge and noticeably slower.

Scanned the car last night, 4 codes in total, first were clutch switch and terminal battery voltage, instantly I ruled these two out.

Other one was:

17956

N75 I believe, actually already rewired this at the plug, break in wiring somewhere or even faulty unit, tho did replace it couple year ago. would this cause low boost issue.?


And 16486 which is the maf, can maf cause lower boost what am experiencing.?

 

[SamHendry]

Forgot to say once these codes were cleared none came back.

Another thing is (I'm just taking stabs in the dark here, forgive me if I'm talking complete pi$$) is it a possibility the actuator needs adjusted, I remember reading something about actuator relaxing on hybrids after bit of use and half turn of pre load added.

Car isn't jerky at all, isn't mis-firing nor does it sound like a leak somewhere although haven't had it pressure tested.

It's still really smooth, almost like it's reverted back to stage 1 power delivery

 

[hydro s3]

What hybrid do you run and at what power is your car running normally?. Hope you get her sorted out soon.

 

[SamHendry]

It's beacbuggy hybrid mate and produced 306lbft 338hp. Hope get sorted soon aswell, little stuck with this one tbh.

 

[Stuart B]

is it possibly a leak somewhere - although I would have thought you would hear it wouldn't you? I do recall tuffty saying the boost pressure isn't fixed, its to do with the volume of air and of course it is much colder this week - but that wouldn't explain the drop in power.

 

[SamHendry]

Yeah Stuart, car was smoke tested when napped but that was in June about 3k miles ago.

Just did a search with regards to actuator preload, came across a welly thread where prior to fitting his hybrid he got bill to check the pre load on the actuator, does anyone have any insight on how this can be done?

Was this thread here: http://www.audi-sport.net/xf/threads/another-hybrid-conversion-thread.104103/page-3#post-1076803

 

[SamHendry]

Faulty boost gauge was the culprit, cheap Sh!te of eBay! Avoid cheap eBay boost gauges.

 

[Stuart B]

so the "loss of power" was psychosomatic? <-- or whatever - "in your head"?

 

[SamHendry]

Yeah I was certain the cars performance had dropped off but I think I jumped the gun slightly.

I tested the gauge using a foot pump, not the most accurate I know but it's definitely under reading,

I took the car for a proper test drive drive and I'm sure it's performing as it always did, hopefully get to the track this Sunday. Event on at knockhill, anyone on here going?