is there a way to connect the boost gauge to the inlet manifold?

its not ideal to do that downstream of the throttle body, because the engine doesnt always make boost, when the throttle snaps shut like on overrun the engine pulls a heavy vacuum and some boost guages dont like this all that much you end up splitting the diaphram in them

Never seen that and I take all the boost gauge connections I fit from the inlet after the TB

its not ideal to do that downstream of the throttle body, because the engine doesnt always make boost, when the throttle snaps shut like on overrun the engine pulls a heavy vacuum and some boost guages dont like this all that much you end up splitting the diaphram in them

So let me get this right, downstream as in front of the TB, yeah ??

So the FPR pipe is ok then ??

I'm such a noob sometimes

Downstream is toward the engine with airflow.

Thinking about it now the AEM gauge instructions actually specify it to be connected on the inlet after the TB.

Edited 6 March, 201313 yr by Frisco

So let me get this right, downstream as in front of the TB, yeah ??

So the FPR pipe is ok then ??

I'm such a noob sometimes

It doesn't matter, the vac system is effectivly a sealed system, if it wasn't, you would have a constant vac leak

The throttle shutting etc, will have the same effect on a boost gauge no matter where in the line it is connected.

The throttle shutting etc, will have the same effect on a boost gauge no matter where in the line it is connected.

yes kind of, except on the air filer side (upstream) of the throttle body there is no heavy vacuum on overrun, it just goes to normal atmospheric pressure once the recirc valve hs purged the charge to the airbox. if the boost gauge was the other side it would go into negative numbers at certain points/operating conditions, in fact that's exactly why the brake servo vaccum reservoir is connected directly to the intake manifold so that it replensihes the vacuum via a non return valve

edit;

this is where i would connect a boost gauge to one of these

rocker cover gasket ok? caused me poor idle for some reason , changed y pipe and s pipe on mine too idle tiny tiny bit off but its perfect to drive

rocker cover gasket ok? caused me poor idle for some reason , changed y pipe and s pipe on mine too idle tiny tiny bit off but its perfect to drive

Yep done last year, Y pipe is ok, S pipe done a few years back, I may give it a closer look later just to triple check.

Unclip the pipe going into your charcoal canister, to see if anything changes.

Just tried this .... The same, does that rule out a fueling issue ??

Another thing noticed is that if I'm sat on sat 24mpg, when I start the car again it will drop up to maybe 0.5 mpg within a few seconds of turning the key

mine averages 19 round town as is

mine averages 19 round town as is

Thats bad lol

Normally i can hold about 23 round town, at the moment I'm struggling to reach 19

Just tried this .... The same, does that rule out a fueling issue ??

Another thing noticed is that if I'm sat on sat 24mpg, when I start the car again it will drop up to maybe 0.5 mpg within a few seconds of turning the key

Not nessesarily, but might rule out it being an issue with your charcoal canister

You need to do some logs of block 001 to see what the fuel trim is doing.

A quickie from the slow trip home.

O2 looks quite sporadic. Not 100 percent sure what that means though

LOG-01-001-020-xxx.CSV

A quickie from the slow trip home.

O2 looks quite sporadic. Not 100 percent sure what that means though

Mine is also a bit all over the shop.

You really need a log of it, when your at full throttle, full boost and it starts playing up.

You really need a log of it, when your at full throttle, full boost and it starts playing up.

I'll sort that for later.

Didn't manage a run last night, got one in this morning, I've added markers at points where I opened it up a little, still not a full 3rd gear run though. But there is more varied engine speeds.

LOG-01-001-002-020.CSV

I've noticed that on idle there's some large minus figures on the O2 sensor, thats trying to lean the mixture out IIRC ??

And I seem to recall anything over +/- 3 being bad, am I right ??

Oh yeah if it was pulling timing the figures would be minus right ???

Well it's hard to say, but certainly when you go around the 5000 - 5500rpm area your trims are doing similar things to mine.

I could only see 2 noticable jumps in all that though, 1 being 15.9 and the other 13 something.

So it's possible you have a similar issue to myself, but as you know, you need a few good runs hard into 3rd gear at high rpm.

Nip to that local airfield on your way home later

Also log blocks 001, 031 and 032.

This will give a better picture of what your fueling is doing then hopefully.

Also block 117 might help as it will show what the ecu is doing with your TB.

Nip to that local airfield on your way home later

Also log blocks 001, 031 and 032.

This will give a better picture of what your fueling is doing then hopefully.

Also block 117 might help as it will show what the ecu is doing with your TB.

Yeah I'll call in the airport

There's a couple of pipes under the inlet near the dipstick that aren't visible. I had it on mine, it was only till I got my hand round them that I noticed one split, worth a check.

As to the boost gauge mine was plumbed in straight to the inlet once the sai system and all the associated crap was removed, never had any issues.

Had a fiddle last night and changed the S pipe, Vacuum has gone up a little to bang on -25.

The pipe looked fine to be honest.

I'm out of ideas but the boost leak tester has arrived so I'll give that a shot later.

ANother log as requested

LOG-01-001-031-117.CSV

Had a fiddle last night and changed the S pipe, Vacuum has gone up a little to bang on -25.

The pipe looked fine to be honest.

I'm out of ideas but the boost leak tester has arrived so I'll give that a shot later.

ANother log as requested

LOG-01-001-031-117.CSV

Yours looks like it is behaving itself much better than mine, the fuel trims at high rpm are stable unlike mine.

Yours looks like it is behaving itself much better than mine, the fuel trims at high rpm are stable unlike mine.

So I take it thats good news, what am I actually looking at in those figures ??

Mine was trying to add 20% more fuel around 5500rpm for some reason, so the trim would show 18 or 19 and at this point it would close the throttle as it thought it was running lean even though it wasn't. Which is why it was suggested I needed a new fuel pump.

Bung up a copy of your log, I'd be interested in looking just to see if I can spot the difference

Bung up a copy of your log, I'd be interested in looking just to see if I can spot the difference

I haven't got any of it from before it was mapped.

This 1 is from the other day, the first section of it is with the old fuel pump, the 2nd 2 sections are with a brand new cupra R pump fitted.

LOG-01-001-031-032.csv