Right, in the quest to sort my fluctations etc, today I've removed the SAI & N112, along with the Combi valve and blanked that off. I've also bypassed the N249.

Although I have technically removed it all, I have left the valves and some pipework under the plate that bolts to the front of the inlet manifold, as I wanted to retain the plastic trim that attaches to keep the engine bay looking tidy. Anything else that had anything to do with the N249 or N112 I have blanked off as they are obviously not used anymore.

The plus side is the car appears to idle better, and under normal driving seems much better, but under full throttle I get a nice amount of boost, for a second or so, and then I hear the DV opening, even though I'm at full throttle!? I have never experienced this before todays removal of the above.

It's weird, the car seems to have 'the potential' to produce good boost, by that I mean it now feels like what I would expect it to feel like, but then just when you think all is well, you hear the DV 'dump'. I can also hear what sounds like the boost fluctuating on and off (you can hear plenty of boost, then the noise dies off temporarily, then comes back etc...)

The car is standard apart from Compbrake DV, K&N panel & Catch Can.

Any ideas?

Edited 17 March, 201214 yr by sjh1986

Have you piped the dv to the inlet manifold where the valves connect

Yes, vac pipe directly from underside of inlet to top of DV.

Sorry - forgot to specify that.

Have you disconnected the valves under the plate

The electrical connectors are still plugged into both valves

Is the compbrake valve adjustable? Try tightening it up a bit. If you have a remap it needs to be quite a bit tighter than normal.

That's a good question, I don't know to be honest. You can obviously unscrew the cap to get access to the spring, but no idea if loosening or tightening adjusts it. As far as I am aware the car has not been remapped.

Just a little update though...

I've just been out in the car, and it drove extremely well, the best it has ever driven whilst in my ownership! Next to no stuttering, no boost fluctuating, and good power right up the rev range. I can hear a difference in engine note which sounds like it actually has some power higher up the revs now, rather than it feeling/sounding asthmatic. Now, it's rather cold outside (about 3 degrees) so I don't know whether it was just because of the cold air, or that the ecu has now adjusted to the fact that maybe I've cured some problems.

Is that feasible?

Edited 18 March, 201214 yr by sjh1986

That's a good question, I don't know to be honest. You can obviously unscrew the cap to get access to the spring, but no idea if loosening or tightening adjusts it. As far as I am aware the car has not been remapped.

Just a little update though...

I've just been out in the car, and it drove extremely well, the best it has ever driven whilst in my ownership! Next to no stuttering, no boost fluctuating, and good power right up the rev range. I can hear a difference in engine note which sounds like it actually has some power higher up the revs now, rather than it feeling/sounding asthmatic. Now, it's rather cold outside (about 3 degrees) so I don't know whether it was just because of the cold air, or that the ecu has now adjusted to the fact that maybe I've cured some problems.

Is that feasible?

That is feasible as the cooler the air the better the boost.

I removed all the SAi, N249, N112 I also removed everything from the metal bracket to inlet manifold and refitted it as i also wanted to fit plastic cover back on. DV must be tight also check you have good connections to inlet manifold for DV and tight clips. Also check Inlet manifold has not lost any blanking plugs or T's when you did the removal process.

Just checked all connections and clips and all are tight. Just hooked a boost gauge upto it and did a WOT test from 2k RPM in 3rd, which held around 0.6-0.7 BAR. If I do the same in 2nd gear, it spikes to approx 1 BAR, then settles and holds at 0.6-0.7 as per 3rd gear.

I assume the above sounds about normal for a standard car? I might stop playing around with it now lol, I'm going to book it into R-Tech at the end of the month for a Stage 1 Custom map, so I think I will just leave it for them to give it a once over before mapping it.

That sounds about right, they hold at about 10psi standard which is 0.7bar

fantastic, sounds like im making progress then! These cars must be brutal when they are mapped, as it's already bloody quick now i've sorted the boost issue! Clearly it was getting bugger all boost before as it goes like a bullet now!

It's taken a year but i think i've just fallen in love with it!

LOL you'll find it quite different remapped, with most stage 1 maps it'll peak at 1.3 bar and hold at 1 bar. It will pull and pull in every gear. Imagine 3rd feeling like 2nd and 4th feeling like 3rd you get the idea.

Brilliant It's taken me ages to get over having to sell my Integra, but now i feel much better!

See what its like when the weather warms up, I'm just wondering if it could be the cts playing up?

I did wonder that... A couple of weeks back the temp gauge went close to the red, but the coolant was actually fine so I think they gauge threw a wobbly. I will keep an eye on it and probably replace if it does it again.

Is the IAT on the intercooler likely to cause funny business if it is a bit poorly?

I did find mine did some funny things when the coolant temp sensor was giving up the ghost. If the CTS gives the ECU a spurious temp reading (like a lot colder than it really is) the ECU injects way more fuel.

I was sat at some lights and pulled away and all of a sudden it felt like a remapped car, I couldn't believe it... but then ten seconds later the gauge was in the red and I had an engine management light which had me panicking but the coolant wasn't boiling so got it to a garage and it turned out the cheapy CTS I had bought and fitted the week before was knackered already.

So yeah, a failing CTS can affect the performance. It will also kill your fuel economy.

If you don't use the car much you might as well leave it for R-Tech to check and replace when they do the map.

MPG isn't too bad, If I hoon it around it will do circa 23-24, and easy driving will do 29-32 depending on the outside temperature. I'll probably leave it for now to be fair and let RTech sort it, My Mrs drives it most of the time anyway and she wouldn't notice if a bloody wheel fell off lol!

Edited 19 March, 201214 yr by sjh1986

Easy driving should show atleast 34mpg+

Easy driving should show atleast 34mpg+

Even on short journeys? It will do circa 40MPG cruising on the motorway, but short town driving I get around 30 ish.

Are you measuring it manually or using the dash readout? The dash readout can be about 10% optimistic.

They generally get (on the dash) anywhere between 30 and 35mpg average with a mixture of driving. 40+ on long motorway journeys at a steady speed and low-mid 20s if you're caning it or doing a trackday.

I try not to take much notice of the dash reading as I know they're not that great. It tends to do around 350 ish to the tank, which is circa 29-30 MPG. I don't drive it all the time so I don't know what it's capable of. I am more sympathetic than my mrs when it comes to trying to be economical, but then again I have this problem with my foot...when I see a long road it tends to become all heavy and jams the loud pedal to the floor lol

Edited 19 March, 201214 yr by sjh1986

Ok, so just took the car out for a bit of a run to test it in some more mild weather conditions. Obviously it wasn't as pokey as at the weekend due to the increase in temperature, but i did notice it holding back ever so slightly, and slight boost fluctuations. I'm thinking there must be a reason for this, and i'm wondering about certain temp sensors, coolant or intake air temp? Just seems weird that it runs faultlessly when outside temp is very low (less than 5 degrees).

Any suggestions from you gurus?

What is the actual coolant temp reading (accessed via VAG COM?). It may well be this if its gone a bit doolally.

I don't have a copy of VAG-COM yet unfortunately, so I will have to find someone who has and see if they could have a look for me. For what it's worth I may just replace it anyway, as it did throw a wobbly the other week and tell me the coolant was boiling, when it was fine... Scared the s*** out of me when I looked at the gauge though lol.

Worth a go I suppose, a genuine new coolant temp sensor is £29 from the dealers or TPS though. If that doesn't help you could always stick it on ebay for a few quid less than what you paid.