laster969 said:

Like the video just made my own boost leak tester.

Click to expand...

Good now go through and fix those leaks.

Updating thread:
Made a ramification on the leak test the way to also pressurize the top of the BOV during the test. Now the Audi/VW OEM BOV hold impressive 25+ psi, with no leaks at all. Here's the procedure I went through: pressurized 5 psi, cut the air supply and watched the boost gauge. Pressure didn't drop. Went to 10 psi, cut air supply: still no drop. Then 15, 20 ... at 25 psi the cap covering the hose exit to TB blowed off from the clamp. Well, I still could go until 30 psi, end of the gauge scale, but with twice the maximum boost, I was pretty satisfied.
I still had to test for leaks this way to the stock BOV, to assure it was bad. And yes, it is! With the top of the BOV (vacuum line) also pressurized, the valve still couldn't hold more than 2 psi, probably what the spring can hold by itself. Diaphragm does not its job anymore.
Throw Audi BOV in again and intake hose connected to TB. Tested for leaks: took 30 sec to drop form 15 to 10 psi and an entire minute to drop form 10 to 5 psi. I guess it must be fine.



I used generic radiator hose pieces to adapt the BOV exits diameter to the car hoses.







Time for a highway test. Still no success!
Throw new NGK BPR6ES plugs in. Took it to the highway again. At this time, to release a bit of my frustration, something changed!!! My car is holding much more boost and I feel it pulling strong at medium rpm range. Sputtering still happens when WOT or/and high boost.
I will take the new plugs out today to check the gap (0,7 - 0,8mm right?) and compare to the old plugs gap. Maybe this performance improvement came up from different electrode gaps – wider before, little closer now – worth to check. I'm also getting ready to order new NGK plug wires and new coils.
PS: I also made the water-spray-over-plug-wires test last night, to check for bad insulation, but nothing drew my attention.

Mike_GST said:

About the vídeo-tutorial, it shows they got 30psi, after fixing the intercooler. On a stock GST, what's the pressure I should look for as a target? As I'll have to work with the hoses, would't be worth replace them for new ones?

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You should test for 15 PSI. I belive stock boost is around 12 psiish so overshooting that mark by 3 psi would be on the conservative side of doing a BLT on our cars, but it will help you pinpoint leaks faster as they will be making more noise at 15psi. From what I have read and heard from turbo gurus is that you should NOT be testing 25-30 PSI or whatever when your car only boosts at 15 PSI. You could potentially be CREATING boost leaks at that point blowing out seals and blowing off hoses, Someone correct me if I am wrong here.. You mentioned in the earlier part of the post that the car had low miles but sat for a long time? Maybe the oil residue in the PCV valve hardened or gunked it up over the duration of the sitting time?

To check the PCV take it off the car
1) Put the threaded side to your mouth and suck air in. if it closes and blocks the air your PCV is working fine.

If not go ahead and shoot some carb cleaner in it let it dry and repeat step1

GAP:

Another common question is in regards to the proper gap of a spark plug. This refers to the space between the center electrode and the side electrode. The average auto-parts store computer will usually suggest a gap for each spark plug that they have in their computers. However, in most cases, the best gap to use is the one specified by the manufacturer of your car. In the case of turbo DSM's, many people choose to gap their plugs to .028". DSM'ers have had good experiences with slightly larger gaps (.030-.032") as well as with smaller gaps (.026"). The computer where I work suggests a gap of .032" for the spark plugs for our cars.

Spark plugs do not come from the factory pre-gapped. You may open a spark plug up and find that it meets your gap needs, but this does not mean that the next identical spark plug will have the exact same gap. To be sure, manually gap each spark plug you install. There are several tools to help you measure a spark plug's gap. Here are three of the most common: a gapping disc ($.99), a blade measurer ($3) and a wire-gapper ($3). What you use is your preference. Many people say that the ramp-style gappers are not as accurate. They'll work in a pinch, but the wire and blade gapping tools are preferred.

To sum up: In general the BEST spark plug for our cars is the NGK BPR6ES gapped to .028", varying heat range depending on modifications.

Click to expand...

Check out the link below for the full spark plug FAQ.

http://www.dsmtuners.com/threads/spark-plug-faq.233421/

I took out the new NGK BPR6ES and they're gapped right .028". The old ACDelco that were in before are .031". Then I gapped the Delco plugs .023" and mounted them just for a test run. Still sputtering in high boost and/or WOT, didn’t notice anything better or worse.

I repeat the water-spray-over-plug-wires test again, but today completely in the dark. After insisting for a while revving hard, suddenly a weird tiny shine drew my attention right in the corner where the cables 2 and 3 are attached to the valve cover. It took some time to see that flashing again, but it happened and also saw some near the coils.

Took the cables out and measure their resistance. Follows the comparison of the measure I made 2 months ago to the one I made today, in kOHMs:
Cyl 1: 4.6 - 4.9;
Cyl 2: 5.8 - 6.8;
Cyl 3: 5.8 - 6.2;
Cyl 4: 8.7 - 9.3

They are getting worse probably because I'm handling them very much lately!
Will provide new NGK wires.

Thanks coloradotuner. I got excited about this ordinary BOV performance. I read a lot of people saying plastic BOVs are crap and so on. But looks like they’re not bad at all and I wanted to test its limit. What you said is totally right, gotta control myself next time I didn't know about the PCV valve, will take a closer look to it and do the test you told.

Thanks for the link UTZ_3.

Secondary coils resistance reads within the range (11.3 - 15.3 kOHMS):
1-4: 12.93 kOHMS
2-3: 13.29 kOHMS

Didn't read the primary resistance yet because to get there demands to remove the fuel rail the way to take the coils out.
I'm gonna wait for the new wires and test them before go ahead and disassemble more stuff.

My NGK wires shot out after just a few months and started arcing to the hood so I repositioned the coil so that the wires didn't make a hard bend. I ended up mounting the coils on top of the intake, flat so that the wires only ran straight. I fought it for the better part of 6 months, testing and changing lots of things, never ever thinking my new wires were the culprit but I grabbed a used no name set off of one of my donor cars and problem solved. Just my experience and I hope that new wires fixes yours too.

Thankfully all the parts I changed until now were not a waste of money.
1) The BOV was proven bad;
2) The plugs in there were not the best cost-benefit choice and I never realize if their specs were right for this car. Their gaps also were little too far;
3) Fuel filter could be stuffy because of the tank flushing, can't say, anyways this is a regular maintenance part, so whatever. At least now I have a Mitsubishi genuine part instead of a no-brand-black-can. Had a major headache with this replacing and the connections to the filter, but in the end I made a nice improvement that will make much more easy for the next replacements.

How the heck did you see the wires arcing to the hood? Does it leave a mark or something? Thanks for you positive wishes my friend. I'm looking optimist to the wires replacement.

Those are going to be looooong 10-days shipping.

Edit: the money I spent on the boost leak test device was also not a waste, since without it I would never know for sure the old BOV was bad and the ordinary VW/Audi plastic BOV was such a leakproof.

You REALLY want to know?.........I threw an old rag on top of the wires, closed the hood and went for a drive....no more spitting/sputtering. I then took my NKG wires off (yes just a few months on them) and went to my Laser, which isn't running, and stole the wires off of it (just plain old plug wires, no name). Took my rag off and went for another drive, no problems at all. So I removed the coil pack and bolted it to the top of my EVO3 intake and haven't had a problem since. I just got this fixed maybe a month ago. Stupid story but it's the truth. Couldn't believe an old rag helped solve the problem but it did.

This didn't happen at low boost but once I started upping the boost past 15 it started crapping out. Now I am at 30 lbs and still boostin away!

Just like that?! Oh man!
If the new wires don't fix my sputtering and loss of power problems, will give a shot on the old rag throwing method too

Hey, it was just a test. The rag is long gone but a big thanks to it!!!
I think if I had just changed wires it would have solved the problem, but I didn't think a set of 2-3 month old NGK wires would go bad. I attribute the problem to the sharp bend right at the hood that I had. If I still had the receipt I would get a new set for free since I think they have a lifetime warranty on them, but the car is running on those cheapo red wires and doing just fine! Good luck man, I hated chasing my tail for half a year so just wanted you to know what fixed mine.

Since you report all this, I will take doble care handling and attaching the new wires.
By the way, wish I had my engine/bay so perfectly clean like yours. Beautiful!

Thanks man I appreciate that. I scrubbed it really good when I had the motor out so it didn't look like a junker! I don't raise the hood much and just let people guess what is in there since I am trying to keep the "sleeper" look but it is far from a stocker!

Well, turned out new spark plug wires made that whole embarrassing performance just disappear. Since the engine start I could notice a very different behavior. The RPMs jumped to 2krpms and slowly slowed down ranging between 500 and 900rpms. On the road, first pull it bogged on second gear, but after that just pure happiness. Tested all the conditions and no bad episodes at all. When arrived home, idle was steady on 800rpms and the radiator fan wasn’t working nonstop, as before all this mess came up.

I’m not really done with this because the webstore sent me mistakenly the wires for the 1g eclipse instead of the ones for the 2g and the worst thing is that they don’t actually have the ones for the 2g to exchange. I’m stuck with no known options for now, but will return them anyway.

I did ohmic resistance readings on the NGK wires. Conclude that actually my stock wires were not that bad, concerning to the resistance; but as I figure out one night, on high revs, it was sparking somewhere else but the plug. Resistance readings can show you if one wire is bad, but don’t tell you if it’s good. If someone is looking for this numbers, here it goes. Just to make it clear, those wires are for 1g, wire 3 is the longer one.
wire cyl 1 - 3.89 kOhms
wire cyl 2 - 5.24 kOhms
wire cyl 3 - 6.51 kOhms
wire cyl 4 - 6.00 kOhms

One more thing I made before the new wires arrived, just because I had the opportunity, was a cylinder compression test. Though there could be exhaust valve sealing problems or whatever. The results were much more impressive than I ever would expect: 178 – 172 – 171 – 173 psi from cylinder 1 to 4. Awesome!

Will come back after testing it some more to let you know if this was really the end of the thread. For now, I’m convinced that yes. Thanks to everyone that somehow helped me on this.

That's great news Mike. Nothing embarrassing about it, just happiness! I can see the smile on your face!!!


On a side note, I got my new NGK wires on also!!! I also moved my coil to my A/C compressor mounting bracket to keep the wires closer to the motor and away from the hood.

YEAH I didn't think wires would make cars performance change so much, suddenly, since they were the 18 years old Yasakis. I quite enjoyed it at that moment 1990TSIAWDTALON but that bogging on the first pull dont leave my thought. That was the reazon I created this thread, by the way. For now I'm mistrustful, have to test it more in different days to be sure. The cylinder compression test YES, that put a smile on my face from ear-to-ear

I found out a store that will make the wires the lenght I want. Will not have the same quality as NGKs, that's for sure, but hopefully will do the trick.

Post a picture of you new wires layout, I'm curious.

WOW its been longer than a year?!

The new plug wires solved that sputtering performance that I faced in the middle of this thread, but I still had those sporadic huge power missings I wrote about in the first post. I worked hard and read a lot the last months, fixed boost leaks through injectors seals and TBI gaskets; cleaned and tested injectors, fuel rail, EGR valve, EGR solenoid and PCV valve; cleaned TBI and intake; tested coils, power transistor, TPS, idle sensor; did a lot of BL tests... replaced battery and the harmonic damper gave up on me meanwhile (fortunately i had it idling in my garage).

But after all, the problem had nothing to do with it!

Since I very mostly drive the car daylight, took this far to drew my attention the high beams considerably dim when the AC compressor comes in. Started drive the car with the AC off and it's been a month since then had no more hesitation. Even better, my car is getting faster each time I take it for a ride.

I know the AC compressor takes some HP from the engine, but my issue is more related to voltage drop than a little loss from a mechanical engagement. Personally I read this situation as a huge voltage drop every time the AC compressor comes in enough to weak the plug sparks, resulting bad gas burning and the O2 sensor understands it as a rich A/F ratio, making the ECU reduce fuel injection. Consequence: engine bogging.

The voltage comes back to normal after 1 or 2 seconds the compressor comes in, but if this very moment matches with a consistent pull, cars performance becomes a whole mess. And I'm suspicious that the ECU stored those sporadic failures since ever and reduced overall engines giving, which now with the AC off is coming back everytime I hit the right pedal.

Could be the alternator (voltage regulator getting lazy), could be the A/C compressor (clutch getting heavier/sticky to engage). Whatever, I'm so freaking relieved

...much more simple than that!
I gave a hit on tightening the alternator belt and VOILÀ!
For the record, It wasn't really loose, but compared to the other belts, the alternators demands a much more stronger tension.
Thanks everyone.