turbo lag and variation

[Waterloo]

You can try a new cap on the coolant bottle, but I can tell you from experience you may have a head issue. If it is to the point of puking coolant, odds are it won't be long. Mine was so bad it actually blew apart my radiator. I replaced that and then the hoses started to blow. When I finally got her in for the in frame, I had coolant shooting two to three feet into the air out of the coolant bottle. All of this happened in a matter of a few weeks. Just saying... One thing you can check to is your air compressor. Sometimes they will have a bad check valve or other failure that will push air into you motor. There are a couple of ways to test this, but I think it is the head.

You can go to NAPA and get one of their block test kits, some poo poo them hear, but it diagnosed my head in like ten seconds. https://www.napaonline.com/en/p/BK_7001006