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My turbo started to be laggy and unresponsive :(

Hey guys.

cut long story short. I've just had my car dynod 2 days ago and made an impressive 272kw at the wheels on 98. Car drove pretty well and was quick. Although I noticed when driving home on the M1 shortly after the dyno run, my car would be inconsistent with how the boost would come on. This was especially evident in 3rd gear as the intake would sound really loud but the car would not pull.

I didn't think too much of it, only until today my turbo started to feel really damn laggy. I would have to push the accelerator all the way to the floor for the turbo to kick in :( And I can't really hear the turbo spool like it usually does.

The last time I had this issue is when the turbo manifold bolts were loose. I had tightened the bolts and the car was transformed. The the boost came on hard and you could hear it spool nice and crisp. So I thought it would be a good idea to get a mechanic to add a metal gasket between the turbo manifold. 

Once I had the metal gasket installed the car never really felt the same and im not too sure why? Also the bolts were constantly coming loose no matter how many times I would try and tighten them down. Do you think this could be the underlying issue guys? 

I have a map sensor so would a boost leak still cause sever turbo lag?

Any help would be much appreciated.

 

When the gasket was replaced was the turbo looked at?

If you don't have lock tabs the nuts will want to undo always.

 

A Boost leak still causes issues even if you use a map sensor, it just means the fueling isn't thrown right off. I would definitely check the easy things first.

Boost leaks, dead turbo etc

17 minutes ago, Ben C34 said:

When the gasket was replaced was the turbo looked at?

If you don't have lock tabs the nuts will want to undo always.

 

A Boost leak still causes issues even if you use a map sensor, it just means the fueling isn't thrown right off. I would definitely check the easy things first.

Boost leaks, dead turbo etc

 

Thanks for the reply mate.

turbo is brand new and in good condition. I will be getting some lock tabs to see if it fixed the problem. Its driving me crazy!

1 hour ago, Trex said:

boost leak on a map would hunt idle, stutter/shudder under boost, and feel slow.

What ecu are you using? Do some logs and post them here

Hey mate

I'm using a link G4 ECU. My idle dips fairly low and almost stalls at times when I bip the throttle but I do have a forward facing plenum and big ass throttle body.

I had a look at my boost gauge today and I am starting to make positive boost pressure with my throttle all the way down to the floor and at about 4500rpm its at about 5 psi and will increase boost from there. Also my gauge is reading - 20 and its usually at - 18.

Usually I can get a nice vacuum and spool with not even quarter throttle and by 3500rpm im at 8psi. So something is definitely not right.

Its a new turbo so I doubt its blown? :( Ill see if I can post logs for you guys. I'm willing to send someone $50 from pay pal if anyone can solve this issue lol.

Edited by Redknight

I had my car tuned on a dyno once and 2 days later I had no boost and was very laggy. I took the cat off for a look and it was blocked up.

This could be your cause. Undo 2 bolts and shine the torch in there.

 

Update

Driving the car home from work this morning, I noticed my turbo was spooling normal again and had my power back. I parked the car to get something to eat for 10 minutes. Start the car up again and turbo goes back to being silent and can hardly hear it spool, feels like I have the handbreak up when Im boosting and extremely laggy. Also a strong fuel smell :(

Checked the exhaust and no signs of it being blocked. Exhaust place checked for any leaks with a stethoscope and couldn't hear any leaks. I have no idea what else to do :(

I am willing to pay anyone via paypal if someone can solve this issue. Its least I can do to get my baby driving like it should. I have spent so much damn money on this car and I expected it to be right :(

do you guys think its tuning related? I had it tuned at dare motorsport at Lismore NSW.

edit: The tuner added a 3 port solenoid to control boost. Would this cause any of the following issues if it was faulty? 

Edited by Redknight
  • Like 1

Reeks of fuel, faulty plug or coilpack?
Whens the last time you changed the plugs?
I had a coilpack fail and it was real laggy but you could tell something was wrong just low speed driving

Do you have a wideband? Is it possible someone has increased the fuel pressure and thrown the tune out (richer)

Thr fact that it smells fuely when it plays up would make me want to explore that further - too much fuel injection or not enough air getting into the engine

As above, i would take it to the tuner, especially if you dont have a wideband installed. Could take him 5mins to work it out

  • Like 2

UPDATE #3

Omg my exhaust sounds absolutely horrible today. It sounds really tingy or maybe slightly like a tractor? It just sounds terrible and nothing like an RB25. Also the fuel smell is so bad its stinging my eyes while I am driving. Boost lag is horrible and I can't even hear the turbo spool until I get to 5000rpm then it hits 17psi.

Would coil pack issue cause these issues? or maybe stuck wastegate? I have a brand new turbosmart actuator though..

The tuner did put in new spark plugs on the day of the tune. Also a bit dubious that he rejects my calls when I try to call him...

sorry for the late reply guys. I work crazy hours as a security officer. Will post logs as soon as I can. Appreciate everyone's help.

Edited by Redknight

Idle car. Disconnect coilpacks one at a time. See if when you pull one the car still sounds the same (no noticable change in engine note) and that might be your dead coil

Sent from my SM-G950F using SAU Community mobile app

  • Like 1

Anyone living in surfers paradise that is able to help for $100?

I have taken it to several mechanics and no one knows what the hell is wrong with it!

driving home last night I lost all power, strong fuel smell and the throttle is completely unresponsive. The injectors or engine are ticking really loud, almost like how a tractor idles. And turbo completely laggy. 

I took everyone suggestions and disconnected each coil but all I could notice is the engine revs dropped. I am not a mechanic so I have no idea what I am doing. All I know is I spent a huge amount of money to build my car so I can enjoy my pride and joy but its giving me nothing but frustration. I am really starting to hate the damn skylines.

I am desperate for someone to help me out and tell me exactly what the issue is so I can go fix it immediately. 

I am more than happy to pay someone just as much as a mechanic if it means diagnosing the issue. Any member from SAU that is living in gold coast?

I am at my wits end. 

 

Edited by Redknight

I fixed my car!!!!

I did a couple of things. My coolant temp sensor was all green and moldy from corrosion. I bought my self some contact cleaner and cleaned it. One of my injector plugs was not all the way in so I secured that. Also one of the wires on the 3 port was loose so I plugged that back in.

My exhaust started to sound beefier, more bass and I could actually hear my turbo spool! My mid range punch was back! 

 

Edited by Redknight

Well...the issue came back. I thought I had fixed it. 

No mechanic in gold coast can help me. I have no choice but to sell it and be done with skylines for good. I'm done with them.

Its going on car sales today.

appreciate the help guys. 

  • 3 weeks later...

Could be as simple as timing goes off.. Maybe it knocks and the timing gets retarded massively.. causing spooling noises but no performance.. I have seen that too many times than i can count.. take it back to the tuners. Could be a number of things. They'll find the issue 

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