VW Jetta 1.8T


Full member
91 Honda Civic LX
I got this car and started to take it apart. I found a lot of things wrong with it so I decided to tune it a bit. I just don't know where to start. Ideas would be nice. Drop some if you have any.
whats wrong with it ?

coolant temp sensor - if its still a black topped one get a green on in there asap

if your still running the OEM diverter valve the 01 will have the older style which is very prone to splitting. the 03 onwards should have a redesigned part on - but mines still split before 30k. there are several variates available however they must be recirculating

check all vac lines around the engine. again these are prone to spliting - esp the Y joiner on the RHD of the head

brakes have 288mm discs on the front in the UK on the earlier models. im guessing your do as well. get the calliper carriers ( most scrappies will sell them with the callipers on but they, the callipers, are the same as you have ) off a TT and you can fit your callipers to the 312mm disc. from here you can further upgrade to porsche callipers ;) (see my thread for details)

if theres no errors on the engine and you cant find and split hoses then look at remapping it. the AUM engine in the 01 will map from 150 up to around 210. next up for preformance would be the downpipe and a sports cat along with Turbo Intake Pipe (TIP)
front mount intercooler - your temps at least warrant having one quite quickly along with the map tweaked and you should be seeing around 230.
after this your really needing to change to a better turbo
I'll try this when I get a new engine. When I took out the engine every single valve was down and bent not including that 3 of the pistons were fully cracked and the other on is almost cracked. A lot of the wiring is gone because of how they ran it (engine was changed once before) so the heat destroyed some of that. Some easier fixes are going to be the water pump, the hydraulic tensioner since that is bad and that messed up the timing belt. So do have a lot of work on this.

Thanks for the help. I will keep you updated.
take it the timing belt snapped then ? or had they done the cheapskate power mod on the MAP sensor - this is where a diode is put across the map sensor so no matter how much boost the tubro gives the ecu never thinks it above max limit. thus allowing you to manually control the boost.
unfortunatly this doesnt mean the fuel is matched and it runs lean

Edit just read the bit about the tensioner
Sorry for the long time it took me to reply on this. I've been working and this got pushed aside a little. This weekend though we dropped the engine back in. The pistons were fine. It wasn't fully cracked just dug into a little when the piston rammed into the valves. So we sanded those to down. We changed all the seals gaskets. Did nothing to the pistons. Replaced all the valves. When we put it back together we did a compression test on the ground and we were getting around 50 which is better than the 0 we were getting. So we dropped it in and connected all wires and harness's. We go to start it and the engine is turning over very slowly. The battery we have for this is pretty much dead. We heard that we need to get a new battery and then wait a couple minutes for the computer to relearn everything since it's getting no spark and injectors are not firing. The other issue is that it won't shift into 2nd or reverse and now it has a 6th gear. Any ideas?
you will need to play about with the selector to get the gears sorted out.

the computer relearning everything with take around 100 miles - or 2 minutes with vagcom
Okay I was wondering if we just got them switched around because now it has a 6th gear. :blink: I'll post on this later. I'm going outside to work on it now.
the 6spd conversion has been done quite a bit, although i dont know why the gears arent really that much closer and clutch/flywheel options are about 3 times the price, did you get the selectors with it ? the 5 spd and 6 spd ones are different
No I didn't do any conversions to it. I think we hooked up the connectors incorrectly because now it can't shift into 2nd or reverse but now has a magical 6th gear.
Right now I'm not even worried about shifting just getting it started. It's turning over which is good but it's getting no spark at all. Each of the terminals that connects to the coil pack are getting over the 11.5 volts that it needs. We get around 12.5 for all of them. We also connected an OBD to it but it says it can not connect to the computer. So we are guessing it's the computer, the coil packs, or the engine speed sensor I believe. Any ideas? Do you have any threads of your car on there? I would love to see it.
We not got the car working :D It was the two stupidest things on the world. The switch to the alternator was plugged in all the way and there was this other switch right below the intake manifold that looked like it was plugged in but it wasn't. Thanks for all the help man. I'll see how I can help everyone here.
sorry mate been away for the last week. was going to suggest it could have been the ignition amplifier on the side of the airbox

aye if you click bora in my signature itll take you to my small thread.
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