boost gauge flutter at 17lbs of boost

[the wrath]

i have a friend that bought a car that sat up 10 yrs and when you get up to 17 lbs of boost the boost gauge wiggles between 15 and 17 car runs fine it has a te34 turbo 42 lb injectors turbo tweak chip 340 fuel pump with hotwire adj fpr.

 

[WSLN 6]

Could be a couple things. Either the wastegate is weak and that is all it can handle for pressure, or you have a cylinder head issue and a bad gasket is causing boost to flutter once you push it.

 

[JDSfastGN]

Chances are its a bad gauge. Ive had lots of issues with my autometer Z series boost gauge. at 23-25 psi it just vibrates back and forth but my powerlogger shows steady boost.

 

[RUQWKNF]

Also, might want to check for the problematic exhaust leaks on the headers and the cross over pipe connections. As well as at the 3-bolt flange. I've seen exhaust leaks cause this same type of condition.
Just a thought.

Patrick

 

[the wrath]

car does have a autometer gauge too but car has a 17psi chip. i turned up the boost a little it was at 20psi no knock it just pulled hard as hell and it was still fluctuating 18 to 20. i turned it back down for safetys sake. i was thinking the valve springs were bad because it was sitting for all those years. oh and i have a new wastegate that came with the new turbo.

 

[87buickracer]

car does have a autometer gauge too but car has a 17psi chip. i turned up the boost a little it was at 20psi no knock it just pulled hard as hell and it was still fluctuating 18 to 20. i turned it back down for safetys sake. i was thinking the valve springs were bad because it was sitting for all those years. oh and i have a new wastegate that came with the new turbo.

if your one of heads have lifted or bad head gasket you will have boost flutter...retorque head gaskets and put in some ceramic block sealer and see if that takes care of your boost flutter...

 

[1quick87GN]

I had the exact same problem with my car. I had a VDO boost gauge that fluttered. I chased down vacuum leaks, replacing all lines. This did not fix the problem. I ended up replacing the boost gauge and problem solved.

 

[turbo nasty]

When mine was fluttering lik ethat I tried all and finally I pulled the rockers and PSI'd from the compressor inlet to intake. Found all kind of leaks, 3 ports on the intake manifold gaskets, all the fitting on the alum vac bloc, egr stem, etc

 

[jpwalt1987]

bad gauges

Just went out and did some tuning. Autometer Z series boost gauge showing 17-19psi fluctuating real bad but the BS3 and MAP sensor show steady and about 22psi. I think that the gauge is the culprit. Maybe autometer has some QC issues.

 

[JDSfastGN]

Just went out and did some tuning. Autometer Z series boost gauge showing 17-19psi fluctuating real bad but the BS3 and MAP sensor show steady and about 22psi. I think that the gauge is the culprit. Maybe autometer has some QC issues.

Ill bring this post back up, but yes i believe they do have a QC issue. My Z series reads 25-26 psi when im running 20-21 psi. I confirmed this today my MAP readings on powerlogger

 

[grocerygetter]

Z series is their cheap stuff...I had a flutter like that at 25psi on my sport-comp...come to find out I had a zip tie loose...I zip tie all my vac lines.

 

[JDSfastGN]

Z series is their cheap stuff...I had a flutter like that at 25psi on my sport-comp...come to find out I had a zip tie loose...I zip tie all my vac lines.

Meh for a 55$ gauge, its pretty bad. Ive bought the crappy ones at Oreillys before and they were closer than this. I don't understand how they pass the QC test at the end of the production line being like this. The new gauge doesn't flutter and my MAP readings are steady as a rock, its just off by 4-5 psi. I sent autometer an email, we'll see what happens.

 

[the wrath]

how do you test the gauge for accuracy mine may be off i want to check too.