bogging down when going into last gear (auto)

[Rick504]

New to the forum and the dsm world, I just purchased a 96 tsi 2wd auto last week and it has a weird transmission problem. Under light to moderate throttle transmission shifts perfectly, but when I floor it, it will shift thorough all the gears normally but when it gets to about 75-80 mph and wants to shift into the last gear it boggs down and wont shift until I let my foot off the pedal some and then it will shift. It does this everytime under heavy throttle. Mods are headers, K&N intake, exhaust with cat delete. Also motor was just rebuilt. It has a boost guage and it is not losing boost but it will not shift into last gear with the pedal to the floor.

 

[TunaTalon]

It sounds like you're losing power under boost. At WOT the TSI shouldn't shift to fourth until somewhere around 110 MPH.

Loss of power under boost usually indicates a boost leak. Do a boost leak test before trying anything serious or expensive.

 

[FIBA M - EC17PSE]

It sounds like you’re losing power under boost. At WOT the TSI shouldn’t shift to fourth until somewhere around 110 MPH.

Loss of power under boost usually indicates a boost leak. Do a boost leak test before trying anything serious or expensive.

actually its not just that i had the simi;er problem and it was the ignition boot split a little and was arking and missfiring and that could be the same here check your plugs aswell as it might be clogged up and check the leads

 

[Rick504]

Did boost leak test, I had some hoses that were loose. Fixed those issues so now im holding boost but it wont boost pass 8 psi. Also it is still bogging down it feels like the fuel is cutting out at WOT when I get to about 70-80 mph. Im gonna go and check spark plugs now.

 

[GooeyGus]

did you bypass the boost control solenoid by accident?

it's a little sensor with a wiring harness going to it, with two wires. It also has two vacuum connections. If you bypass this, your boost will drop to around 9psi (or whatever wastegate pressure is)

 

[Rick504]

checked the solenoid it is connected correctly. I found a boost leak in the piping coming from the intercooler and sealed it but I still have not resolved the problem. I also installed new NGK iridium spark plugs. Do you think it could be a fuel issue?

 

[m1nd64m3]

It could be the end clutch