Boost cut?

[ls13coco]

So I started noticing the other day that my boost only hits 8 psi now, 11 previously, and sometimes I can hear the bov going off in succession while WOT while going no higher than 8 psi.

Recently I did the o2 sensor, plugs, wires and ordered a new fuel pressure regulator.
Boost leak? Bov needs to be adjusted even though it was perfect? (aftermarket Greddy bov) or maybe it's a fuel issue that the fuel pressure regulator will help? Its also started running rich and idling choppy like I have a sick cam.. mainly why I ordered the reg.

Its a 97 awd tsi, bought it about a month ago. 180xxx km, stock aside from the bov, muffler and air filter.

 

[Dsmkauai]

Do a boost leak test, also is the bov recirculated? I would do a blt and adjust the bov properly and look over things and go from there. Also check the turbo for play.

 

[Macgyver'sDSM]

+1 to what Dsmkauia has posted. A boost leak tester is probably the best first item you can use on a turbo motor. It might just find you some cheap horse power.

 

[ls13coco]

Great, thanks guys. Interesting that the bov was holding fine before but hopefully finding the issue will be this easy!

 

[ls13coco]

Haven't gotten to the boost leak test yet, but I replaced the FPR to no change. I must also add that aside from the uneven choppy idle, there is a snap/crackle sound coming from the motor at idle, close to the fuel rail.. can't for the life of me figure out what it is, or any car buddies.. or the shop I got it from which is when all this problems started. They did the crank position sensor and I did the fuel pump, after the shop though all these issues popped up including major clutch slipping which I fixed and an exhaust leak just before the muffler due to a hanger tearing off.

 

[93AWDDSM]

You're going to be wasting money replacing parts without doing a BLT. That crackle sound by the fuel rail could be old dried out injector seals leaking...wouldn't see unless you did a BLT and soapy water or some other method. You need to do a BLT first off.

Do you have a boost gauge and if so, what the does the gauge read at idle? Anything lower than -18 in Hg Is potentially a leak. Mine sits at -18 to -20 in Hg on my gauge at idle. When I'm in deceleration (foot off gas just engine braking) it reads all the way up to -24 in Hg

What degree is your ignition timing set at? 5* BTDC hopefully..



Edit: are you using the stock 2g BOV? If so those are a known leak. Preferably, the simple upgrade for cheap would be a 1g metal BOV.

 

[ls13coco]

You're going to be wasting money replacing parts without doing a BLT. That crackle sound by the fuel rail could be old dried out injector seals leaking...wouldn't see unless you did a BLT and soapy water or some other method. You need to do a BLT first off.

Do you have a boost gauge and if so, what the does the gauge read at idle? Anything lower than -18 in Hg Is potentially a leak. Mine sits at -18 to -20 in Hg on my gauge at idle. When I'm in deceleration (foot off gas just engine braking) it reads all the way up to -24 in Hg

What degree is your ignition timing set at? 5* BTDC hopefully..



Edit: are you using the stock 2g BOV? If so those are a known leak. Preferably, the simple upgrade for cheap would be a 1g metal BOV.

Thanks man, some good info there. Having trouble finding a boost leak test setup so may have to make my own as testing that is priority now. The other fixes were probably called for though, the car was sitting since 2012 aside from the odd drive here and there (insurance on the plate ended 2012) so didn't go too out of the way.. just general part replacement. Fuel filter today, should be fun..

Clutch keeps un-adjusting on me too, and depending on the adjustment it will sink on left turns but doesn't seem to make any of the noises associated with crankwalk. Hopefully finding and fixing boost leaks will help most of my issues.
Funny, first 2 weeks the car was perfect then timing belt slap, crank position sensor went, fuel pump, front brakes seized, and then everything I've already mentioned. Lol.

 

[doubleclutch]

You have crank walk.

Crank position sensor failure and clutch falling to floor on left turns. Both indicators of walk. Maybe check the endplay?

 

[93AWDDSM]

You have crank walk.

Crank position sensor failure and clutch falling to floor on left turns. Both indicators of walk. Maybe check the endplay?

Unfrontely, I think he's correct. I had crank walk happen to me. Symptoms started as hard left turns with clutch sticking to floor, progressed and then one day started tearing through 3 alternator belts and on way home from parts store getting a new one it walked. This was all
Within a 2-3 month period on a 1g 7 bolt.

 

[mitsubishikid]

if you find that crank-walk is your problem, it might be a good time to swap in a 6 bolt motor.