R32 Gtr Half Boost

[hazerb30]

Hey Guys,

My GTR wasnt pulling anywhere near as hard as usual last night. I watched the boost guage and its only hitting 0.3 bar and sometimes might make it to 0.4

So im fault finding and could use some help.

Its a pretty much stock R32 GTR 140'000kms.

Standard computer

I believe the turbos are the standard ceramic ones still.

Aftermarket exhaust

I believe the boost restrictor may have been removed but to be honest ive never checked. I think it goes to near on 1bar so i think its been taken out.

Engine sounds normal, no change or nasty noises. Drives fine im just keeping it off boost now until i get it figured out.

I didnt hear any pop or bang noise or any 'moment' when it went wrong.

No bad exhaust smoke

I had a compression tester available a couple weeks ago so i did that for interest sakes. 160 to 164 accross all which i believe is good.

From reading posts on here a lot of people said their gtr's stopped making full boost because the computer detected knocking or leaning out. They would turn ignition off and back on and then it would make full boost for a while. I tried this and mine never makes over .04bar.

Where do i go from here ?

Edited October 30, 2007 by hazerb30

[hazerb30]

advice anyone?>

My friend thinks it might be the wastegate stuck open on one of the turbos. Im going to pull the intake piping crap out of the way and have a decent look in there.

[whiteboy01]

advice anyone?>

My friend thinks it might be the wastegate stuck open on one of the turbos. Im going to pull the intake piping crap out of the way and have a decent look in there.

Something simular happened to me.

Things to check,

• CAT to see if is blocked
  
• Wastegates to see if there are stuck
  
• While checking out your cat look for tiny bits of exhuats wheel
  
• Check all pipping to and from the turbos
  
• Check all intake pipping as well
  

That pretty much covered it. If you fined you have a blown turbo i have a spare one here. I pray for you it isn't a turbo.

To check for leaks just get some "start you bastered" and spay it all over the pipes and listen to the engine if it rises you have found your leak!

Good luck with it all.

[hazerb30]

Cheers. Ive just got back from pulling it to bits. I didnt get as far as pulling the turbos off cos daam that looks like an all nighter and i didnt have any bandaids

I did get the pipework off them though. What i found:

On the rear turbo inlet pipe there is oil coating the sides and a dribble of oil pooled in the compressor side. The front turbo pipes are clean. What it looks like to me is the oil is coming from the breather hose thats attached to the rocker cover. Its all i can think of that would explain how oil gets in before the turbo. Is this a normal thing to get a bit of oil blowing in and surely this much would be excessive?

Now from what ive read here the worst case scenario would be that bits of the ceramic wheel have gone through the engine and scored the pistons and bores and that would cause this oil covering the pipe. Unfortunately there was no cat in the car to catch any fragments so i cant check there (my friend borrowed it to get his starion over the pits ). To me it seems like i would have to pull the turbos off to see whats happening

I dont know for sure what the turbos are. All I could see was garret 1-2 written on them. If they are the ceramic turbos i dont see any point pulling them off without having replacements ready to go so ill have to research what to get. Anyone in WA that has something lemme know !

There was no 'moment' when this happened. No bang, nothing. just started it up one day and noticed it wasnt pulling very hard. I know the car pretty well so you'd think id notice when something went wrong.

So im thinking of this plan so far:

Compression test to see whats what

Locate replacement turbos

Pull old turbos off and see whats what

Pray for the best

What do you guys think ?

[hazerb30]

Pulled off all pipes to the turbos, checked and reattached

Wastegates are not stuck

compressor blades are still there, cant see exhaust

Reset ECU

ECU Diagnostics are 55 meaning all ok

Ive done a compression test ~160 accross all

Car idles and drives fine, Still only making 0.4 bar

I havnt pulled the turbos off yet. Surely if the turbo went while i was driving it i would get smoke or at least hear the wheel shoot out the exhaust. Is there some other way to know the exhaust wheel is gone besides pulling the turbos off?

Not getting much help here? Im stuck driving an 80's hilux ute with a speedo cable that drags on the road ! i guess i should be appreciative of that..

could it be something to do with the BOV's? how could i check

Edited October 19, 2007 by hazerb30

[whiteboy01]

Pulled off all pipes to the turbos, checked and reattached

Wastegates are not stuck

compressor blades are still there, cant see exhaust

Reset ECU

ECU Diagnostics are 55 meaning all ok

Ive done a compression test ~160 accross all

Car idles and drives fine, Still only making 0.4 bar

I havnt pulled the turbos off yet. Surely if the turbo went while i was driving it i would get smoke or at least hear the wheel shoot out the exhaust. Is there some other way to know the exhaust wheel is gone besides pulling the turbos off?

Not getting much help here? Im stuck driving an 80's hilux ute with a speedo cable that drags on the road ! i guess i should be appreciative of that..

could it be something to do with the BOV's? how could i check

To check the blow off values just put a metal sheet where the blow off values connects to the pipe. So basicly blocking off the blow off value. Did you check the exhaust wheel? Did you spin the turbo wheel and did it spin nicely?

When i lost a exhaust wheel i didnt' here anything but i lost ALL boost. So my problem is slightly different.

Just one more time though, have you checked all the pipes?

I had alot of oil in the rear turbo but i think it's because i don't a have a catch can.

[hazerb30]

To check the blow off values just put a metal sheet where the blow off values connects to the pipe. So basicly blocking off the blow off value. Did you check the exhaust wheel? Did you spin the turbo wheel and did it spin nicely?

When i lost a exhaust wheel i didnt' here anything but i lost ALL boost. So my problem is slightly different.

Just one more time though, have you checked all the pipes?

I had alot of oil in the rear turbo but i think it's because i don't a have a catch can.

I didnt spin the turbo I had to use a mirror to look in the pipe to see the compressor wheel

Ive got a catch can on order so i can see just how much is coming out the breather. Glad i pulled pipes off to see what actually happens now and understand the usefulness of a catch can

Whats the easiest way to get to the blow off valves ? Pull the front bumper off or something?

Thanks for the help!

Michael

Edited October 20, 2007 by hazerb30

[Shane_954]

If your really tricky try and get it to run without the intake on the suspect turbo for a short period of time and see if the compressor wheel spins, should tell you if theres an exhaust wheel there or not.

[whiteboy01]

I didnt spin the turbo I had to use a mirror to look in the pipe to see the compressor wheel

Ive got a catch can on order so i can see just how much is coming out the breather. Glad i pulled pipes off to see what actually happens now and understand the usefulness of a catch can

Whats the easiest way to get to the blow off valves ? Pull the front bumper off or something?

Thanks for the help!

Michael

Just take the front bar off. Easy as 10min job.

I was a bit silly going all that way to the turbos not to spin them!

[SLIPPERY]

still tricky tho....a little spot for big hands

[hazerb30]

i pulled the front bar off. For anyone reading this in future and looking for help. It took a while because i had the find all the screws and some were siezed.

http://www.skylinesdownunder.com/index.php...4&Itemid=44

So now Intercooler and hoses are off. pulled the outside covering off each intercooler hose and couldnt see any splits or leaks. Intercooler looks clean but im going to flush it with 50/50 methylated spirits and kerosene. Ill also take it to a radiator place tomorrow to make sure it doesnt leak.

Buying new intercooler hoses even though these look ok. When i put new hoses on should i bother putting the original rubber outer covers on? see pic

These are the ones im planning to buy . wish they made them in black.

http://cgi.ebay.com.au/INTERCOOLER-HOSES-N...1QQcmdZViewItem

Will check BOV's once i get the intercooler back in. Unless there are checks that can be done without the car running. Theres a pic there of the left one

Edited October 21, 2007 by hazerb30

[whiteboy01]

i pulled the front bar off. For anyone reading this in future and looking for help. It took a while because i had the find all the screws and some were siezed.

http://www.skylinesdownunder.com/index.php...4&Itemid=44

So now Intercooler and hoses are off. pulled the outside covering off each intercooler hose and couldnt see any splits or leaks. Intercooler looks clean but im going to flush it with 50/50 methylated spirits and kerosene. Ill also take it to a radiator place tomorrow to make sure it doesnt leak.

Buying new intercooler hoses even though these look ok. When i put new hoses on should i bother putting the original rubber outer covers on? see pic

These are the ones im planning to buy . wish they made them in black.

http://cgi.ebay.com.au/INTERCOOLER-HOSES-N...1QQcmdZViewItem

Will check BOV's once i get the intercooler back in. Unless there are checks that can be done without the car running. Theres a pic there of the left one

Good Luck with it all. When I replaced most of my hoses i gained about 2-3psi. Made boost quicker and pulled harder.

Don't forget to come back and finish the post for future readers!

[hazerb30]

Thanks man. Ill keep posting as i find things

Having fun pulling stuff apart and seeing how it all works atm. I only get a couple hours a day to really do anything.

Last night i took the intercooler out and flushed it with kero/meth spirits. it does a great job! So ive got all that back in now with new hose clamps everywhere and ill start the engine again tonight and see whats what.

With the BOV valve test, do you mean that i should loosen the bolts and slide a flat bit of metal in there to completely block off their exit and tighten the bolts back up?

[hazerb30]

Its back together again minus the front bar. Still runs great just no change to the boost level. I went looking for leaks in the piping / intake manifold with a can of Aerostart. Couldnt hear any change in the engine rpm.

I read that when one turbo goes it means one of the inlets sucks and the other blows. Both inlets to the turbos are definently sucking air in.

Didnt try out blocking off the BOV's, wasnt confident of doing so.

I think im gonna give up and take it to someone who knows GTR's and see what they reckon.

[SLIPPERY]

you block up the entry to the BOV so it acts as though there are no BOVs in the system. So where the bov joins the pipe. NOT the outlet

[whiteboy01]

you block up the entry to the BOV so it acts as though there are no BOVs in the system. So where the bov joins the pipe. NOT the outlet

Yer sorry i should of been more clear.

Next step is to make a leak tester. Some thing close to this http://www.vfaq.com/mods/ICtester.html.

[hazerb30]

Nice! Off to bunnings tomorrow. So its a case of blocking off both afm's and the exhaust and pumping in air from a compressor starting at 10psi through to no more than 20 psi and look for leaks.

Ill keep yas posted

Cheers!

Mike

[whiteboy01]

Nice! Off to bunnings tomorrow. So its a case of blocking off both afm's and the exhaust and pumping in air from a compressor starting at 10psi through to no more than 20 psi and look for leaks.

Ill keep yas posted

Cheers!

Mike

Yep and just spray water around the pipes so you can actuly here it.

[hazerb30]

ok another collection of stuff that happened last night

Air leaks were almost non existent. Small one around the BOV which tightening the bolts corrected. That was a bit dissapointing as i was hoping to find something.

So we also did this stuff

Checked fuel pressure, went for a drive with fuel pressure guage duct taped to the windscreen. 55psi under load at WOT. It never dropped off with rpm or load.

Used another boost guage for reference and got around 7 psi which means my other guage is correct. (For reference the stock boost level on a r32 gtr should be 0.8 bar /11psi)

Used a air pump with a pressure guage on it and put it on the actuators for the wastegates. Both of the wastegates just start to crack open at at ~0.6bar. this seems too low?

We wired the wastegates shut and went for a drive (now with 2 guages duct taped to the windscreen! ). Still refused to make over .05bar boost

Checked the timing. 20degrees BTDC which is correct

[TTT]

didn't read the entire thread but have you tried to drop the exhaust before the cat and test drive?

basically if you remove the cat (bolts on the dump side and bolts on the cat back side) so you have a gap where the cat was, go for a drive (yes it will probably be loud and illegal).

since there are no leaks, no broken turbo's, the only other thing it can be is the exit..

a collapsed cat will cause a massive restriction.

the above test essentially removes the cat.

if it all boosts up perfect like it should, bolt the cat to the dump pipe but not to the rest of the system.

another drive.. and see what the boost does.

back down to 7psi? - Cat busted.

still up at 14psi (or whatever you have it set to) - pipes/mufflers from the cat back busted.