Overhaulin'

Could I be needing a new turbo in my car...this sound like it?

I have a 2001 VW jetta 1.8T with 123,000 miles the ECU has be remapped/reprogrammed, this was done about 60,000 miles ago stock boost would hit 7psi APR programming hits 18 psi boost what's happening now is I have to feather the gas keeping the boost under 5 psi or it will shutter and cough ( the boost will not hold) unless.....I floor it...it will hit full boost and hold it but there is no in the middle? does this sound like my turbo is going? also I'm thinking about upgrading to one of the Audi TT turbo options which is a direct fit should I rebuild with Audi TT KO4 tubo parts, buy a used one or get a bigger turbo if I need to thanks..... The car was turbo charged factory...it has a small intercooler stock... yes it could be fuel but then why at low boost and not high boost does it hicup??? I'm still thinking the turbo fins could be bent and need rebuilt I know a lot about cars but I appreciate any advice and will consider all points and opinions FYI??? APR Turbo-Back Exhaust is also installed

Public Comments

1. Turbos do not "go". A turbo is dead when the bearings seize up, or it shatters. The problem is that you are over boosting hugely. You may have done irreversible damage to the engine itself. The turbo is causing it to run extremely lean, which causes preignition and detonation. You must run the highest octane all the time to counter this, and/or install an intercooler. An intercooler is not meant to give more power, although it does. It is meant to lower the temperature of the intake air after it has been heated greatly by the compression of the turbo. By cooling the intake air, it allows for more boost before the engine begins to preignite. The easiest, cheapest fix is this: Get a higher flow fuel pump (or boost pump) to keep the mixture rich and run high octane fuel. That is without a doubt the cheapest fix, and it will improve performance also. What you really want to do for the long run is to get a intercooler, so that you dont have to dump fuel into the engine to keep it from preigniting. Since intercoolers are retardedly expensive, running a longer pipe from the turbo to the intake will lower temperatures greatly for much less. You could actually get a splitter and run two pipes and then another splitter at the intake to rejoin them, which would increase surface area and slow down the velocity of the air to allow more heat to escape. It would take no more than an hour to braze the parts together.
2. pull the hose off and see if there is oil in the hose to the intake if so yes you need a turbo