Boost Issue - It's Flat

Your fuelling might still struggle if your fuel pump is tired, the 4bar FPR may have a negative effect because the pump won't be able to meet required pressure
 
I haven't sadly, my XP laptop died so I have been unable to log for ages. I imagine that they were high and the heat soak on a hot day was awful and robbed so much power, the car was just so boggy. I'm about to register my copy of VCDS Lite so I'll have full access to logs soon and I'll post up what this huge Forge cooler is giving me. It's a pretty warm day today down here and on my lunch break I took it for a spin, the difference is night and day in these temps where the car would normally feel slower higher in the revs, it now doesn't and just keeps going. Also the car didn;t seem to progressively lose power like it used to after a few hard runs so it's doing its job whatever the IATs are :).

Sandip, I'm hopeful that owning a low miler might act in my favour here :). We shall see.
 
That sounds good JamJay, cant wait to get mine fitted now. I remember trying to have a race against an Astra GTE 2 gears ago in the summer and I might as well have got out and ran! Though I did have many issues with the car then.
 
JamJay said:
Some maps do, some don't but my IDCs are maxed out so the 4bar will fix that...if only just temporarily while I consider which 440cc's to go for. Saying that I've never heard of a fuel pump failing due to higher fuel pressure and it's rumoured that 3bar was only fitted to help the engine fall within EU emmission and fuelling regs. Either way, the old girl is screaming for more fuel that the 3bar just can't give.
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a tired pump wont maintain 4bar + boost pressure.... New LCR ones will, they are 4bar pumps as std, just running 3bar cos thats all they need to for 225bhp - the reason you heard of the 3bar/4bar tho sounds unlikely
 
I've always said this about my car but for all the cr@p it gives you, it'll reward you double if you modify it right and a FMIC is certainly the right way to go. I don't know how the air flow to your SMICs is on the S3 but I had about a 4" square window for each SMIC on mine for air to reach it, how stupid. The way the car delivered power on the motorway just now was very good, really progressive and no bogging even in 6th gear so maybe you can go get the Astra after all ;). A turbo car with issues isn't really a fighter so I wouldn't worry, I found that out lol. The last NA car I went up against blew his rods, pistons & oil out all over the front of my car...Honda Reliability eh?!

Can you fit the MK2 LCR 4bar Fuel Pump to the MK1, Bill? As in a straight swap?
 
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Hey guys, I think I have the same issue! Although during the last service I noticed that there was a small crack in the pipe going into the vacuum chamber next to the N249! I took the pipe off, cleaned it and taped it up. Since then it seems to have lost pressure, would you think the leak in the pipe caused this? I have an AMK engine (standard), should I remove the N249 and then see what it's like?

How much is the N75 valve and where does it live? Thank you in advance guys.

Read your story JamJay, sounds like you had a hell of a day the other day!!!!
 
cagiti said:
Hey guys, I think I have the same issue! Although during the last service I noticed that there was a small crack in the pipe going into the vacuum chamber next to the N249! I took the pipe off, cleaned it and taped it up. Since then it seems to have lost pressure, would you think the leak in the pipe caused this? I have an AMK engine (standard), should I remove the N249 and then see what it's like?

How much is the N75 valve and where does it live? Thank you in advance guys.

Read your story JamJay, sounds like you had a hell of a day the other day!!!!
Click to expand...

Crazy day & one I don't want to relive, the bad luck reminded me too much of my Peugeot owning days.

If you notice a crack in any pipe that is related to boost then you need to get this fixed. A pin hole in a boost pipe can potentially lead to big power losses. I recommend bypassing the N249 with new undamaged pipe just to rule this out. If you have the same issue as me though, don't discount that you have a dead/dying N75. Are you able to fault scan the car in case anything has flashed up?


badger5 said:
the LCR pump is 4bar (mk1 1ML Leon)
Click to expand...

Lovely, thank you Oracle.
 
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So...

I have bypassed the N249 valve this evening to determine whether this sorts out my issue. I seem to hear the turbo a bit more and the car seems to be pulling a little better, although it doesn't seem right. Will reseting the ECU resolve this as I have been driving it under low boost for a couple of weeks?

Also, if it is the N75 valve then when is it located, is it easy to replace and how much are they? Any help would be grately appreciated.

I was also thinking about a stage 1 remap, where is the best and cheapest place to get this done? Cheers
 
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