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Discussion Starter · #1 ·
Thanks for clicking this topic [^]

Could you please give me some insight in figuring out how to monitor/log the psi values on boost using Vag-Com? I know measuring block 3 shows the MAF in g/s which is fantastic and has helped me resolve a possible MAF fault, however I'm really eager to monitor my boost - i.e see where it spikes. Is 20psi a little optimistic?

If someone could please give me a pointer as to which measuring block the Mk4 Golf uses I'd be really grateful.

I've had the REVO remap for sometime now and while I'm certain there is no boost leak [had a very thorough inspection of engine and components performed as well a log of vag-com - NO DTCs] I just know the car isn't performing as it used to. Once I figure it out it will put my mind to rest and because I'm getting really fed up with the cars performance lately. It's a bl*ody lottery, some days/weeks the car runs fine, others it just lags increddibly, feeling as if I'm towing a heavy load! The engine only has 25k on it, I've had the Revo remap since 4.5k.

I'm really contemplating dumping the Revo and just booking the car into Jabba - they quote upto 230bhp from a remap alone! But then again I might just fit myself a 4Bar FPR and get a 4Bar map loaded. If this doesn't seem to rectify the loss of power, then I'll have no choice but to get a custom map for the car, I guess the generic maps were never going to suite all cars, I should have read more into this from the beginning...

Cheers guys,

Raj
 

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Can't help with Vagcom but as to your performance problem I would suspect the N75H and/or the forge DV. Try putting the standard items back in to compare. Many people have problems with the N75H on chipped DBW cars, as your using an SPS3 you can set the boost with that so the N75H isn't really needed anyway, it could well be causing overboost and putting the car into soft limp. As for the the forge DV when did you last service it and which spring are you running, does the problem only seem to occur once the car is warm?
 

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Get it down to Jabba! Mike squeezed 233bhp outa mine.... puts over 200hp on the tarmac... has got a few other bits on, turbo back Miltek and the other usuals but my car has always been a bit of a "friday" car and standard ones nicely loosend up roll more Hp than mine.......
 

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RS2002

I'd have a look at the stuff that Eddy has mentioned before doing anything drastic!

If that doesn't sort it out, surely a call to Revo HQ or whoever installed it should be your first port of call?

(Just thinking that it'd be a lot easier on the wallet if you could get it sorted without having to spend another 500 quid!)
 

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quote:

Originally posted by Josh_PoloGTi

RS2002

I'd have a look at the stuff that Eddy has mentioned before doing anything drastic!

If that doesn't sort it out, surely a call to Revo HQ or whoever installed it should be your first port of call?

(Just thinking that it'd be a lot easier on the wallet if you could get it sorted without having to spend another 500 quid!)
Yeah, sorry, by recommending Jabba I wasn't suggesting you get a remap! Stick with Revo and find out what the problem is. I suspect it will be the N75 or the forge DV though as people have problems with these very often.
 

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I ain't no effin padawan
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Log the block that gives you requested and actual boost. somewhere around blocks 115-117 I think.

If you're running standard revo settings, you should see 2200 across the mid range, droping to 1.7ish at 6-6500rpm

As eddy says though, ditch the N75h, and check your DV and piping for leaks, and service your DV if it's an aftermarket one.

Also worth reseting your ECU. Turn the car back into standard, then back into performance, or disconnect the batery for a couple of minutes.
 

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Discussion Starter · #11 ·
Many thanks for the replies fellas [:)]. I've decided to ditch the N75 and pop the stock one back in, as for performance, the car drives perfectly in stock[180bhp] mode so I'm sure there is no leak anywhere. I have however notices [rather alarming actually] that the hose which connects to the top of the Forge DV is beginning to show signs of wear, I think it's been rubbing against the engine cover. However, it doesn't look as if its torn or punctured it in anyway, just left some scuffs on it - Should I be concerned with this? Surely I would get a DTC thrown if a hose was damaged, right?

Oh, I noticed that there was mention of "service your DV" - I have never once done this and have actually been informed my a mate who is a mechanic that you only need to do this on DVs once every couple of years. I had my Forge DV fitted about 5 months ago..... so I've got about 19 months to go before it requires anything done, perhaps I should void his advice and have it done anyway...

I'm going to log the 115-117 in vag com - thanks for the pointer and range I should be looking for.

Will keep you informed on the outcome.

Cheers guys,

Raj
 

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Oh sorry yes wasnt saying spend more hard earned.... get the dump valve serviced and put your original N75 back on perhaps.....?
 

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You will find quite a few people on here service there DV every month/1000 miles, it's very important as the forge DV relies on the grease on the o-rings to form an air tight seal. Also forge advise that the spring supplied as standard in their DV's is only designed to work with standard boost. I had a similar problem and found that an uprated spring in the DV helped alot. Have a look here:

http://www.forgemotorsport.co.uk/vw18t.asp?cat=vw18t&product=FMDVTUN

If you still have the standard DV and it is in working order then give it a try.

Also once the problem is sorted have you considered the 4 bar fpr upgrade for a bit more power.

Be sure to let us know how you get on.
 

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Discussion Starter · #14 ·
Now that is VERY interesting!! I had no idea it required servicing so frequently!! I'm going to place an order for the springs, there 4 however; red being the strongest [and in all probability is only required for larger turbos; k03 sport need not apply [;)]], which would you advise I use? I'm also thinking of changing all the hoses inc. the TIP for the Samco. However, Forge ask you to specify what engine code you have, I'm clueless.... I have a 2003 1.8T 180bhp, is this AWP? Has anyone else upgraded their hoses/TIP does it make a noticeable difference?

Will definitely update as soon as I get this problem sorted, as I'm sure there are many others who are or will [sorry to jinx] face a similar problem.

Cheers,

Raj
 

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You will probably find the blue spring suits your setup well. I doubt you would see any gain at all from changing the hoses. The TIP is wortwhile, although they ask for engine code they only have one design as far as I know, your best bet is to phone and order, they don't bother asking for the code over the phone. I have the TIP on my non-DBW and it made a noticable difference to both performance and sound, I also managed to get a 10% discount just by asking. For your info the guy that gave me the discount was called Peter.

Also have you noticed if the problem seems to occur once the car is warm as others who have had problems with the forge DV seemes to have more problems once the engine was warm.
 

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Discussion Starter · #16 ·
Cheers for the info regarding the hoses, and not to jump on the bandwagan, but yes! I have noticed that the performance is detrimentally worse over a given time, after driving for an hour or so I would say. What would this suggest? A heatsoak problem [in this weather, surely not!]. The car just feels "sluggish" after a while and is very close to the level of performance you get in stock mode, only not as smooth and linear as that is.

The Forge springs are starting to look very promising, just hope I haven't set my expectations too high.

Cheers mate,

Raj
 

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I don't think it's heatsoak as such. More of a problem with the forge DV when it gets hot, not sure exactly but maybe the spring becomes more 'pliable' when it's heated, which would make sense as it's metal. Alternatively it could be the lubricant that forms the seal becomes more liquid and allows boost through.

Before you order anything I would advise swapping back to the standard DV and N75.
 

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Discussion Starter · #18 ·
This weekend I'm gonna remove the N75 and stick the original back on along with my OEM DV. Will post how that gets along.

Thanks for the help,

Raj
 

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Discussion Starter · #20 ·
Well, I was busy over the w/end so I simply reset the ECU via disconnect of battery, you know the throttle body recalibration... and guess what, the car is running like a dream! Even had a play with an old M3 down Marlow [friendly at that] today, very pleased with that car at the moment [:)] Still am craving more power though...... How is your K04 setup running so far? Must be nice to maintain more boost up in the higher RPMs, once my car hits 120mph it runs out of serious puff.... perhaps thats a good thing!

How about your car, all fine? Did you get any benefit out of that blue spring for your Forge DV? Am contemplating ordering one but don't fancy the look of the disclamer that reads "damage to turbocharger could occur" if you unnecessarily install one.

Cheers,

Raj
 
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