1HDT boost indications fluctuating (2 Viewers)

[Jeff Cooper]

1990 1HDT and my boost indications are fluctuating during steady state operation. Normally tops out at ~10psi, now will indicate as high as 17psi, but will drop to about 8 or 9 with no change to throttle position or load on the engine.

Any ideas what I should look at?

I honestly don’t even know where the boost is measured.

Thanks in advance,
Jeff

 

[mudgudgeon]

Probably start by figuring out where the boost line is coming from.

Is it securely connected?
Is it oily? They can get choked with oily gunk
Is the wastegate line intact?
Standard turbo?

With such vague info in your post, it's going to be hard to give helpful responses

 

[Jeff Cooper]

Probably start by figuring out where the boost line is coming from.

Is it securely connected?
Is it oily? They can get choked with oily gunk
Is the wastegate line intact?
Standard turbo?

With such vague info in your post, it's going to be hard to give helpful responses

Thank you for the reply. I checked all of the connections and they seem to be solid. There is some oil residue so maybe I’ll try to clean everything up. The waste gate line seems to be good.
Yes, a standard Toyota turbo (C-26 if I am not mistaken)

Thanks again