2.3T running terrible when warm...

New video:

http://s9.photobucket.com/albums/a87/pay...G_0556.mp4

Man if I still lived in MD I'd be up there in a heartbeat. now it's a minimum 3 hour trip for me to get up to DE.

1 - did you mention that the o2 sensor in the turbo outlet elbow is a 3-wire? If so what wires are being used? The stock O2 sensor is a single wire. Paulie (and I'm sure others, too) uses 4-wire O2 sensors to eliminate the signal return wire being mounted directly to the turbo. What I'm getting at is the "ground" wire for the O2 sensor needs to go pin 49 of the 60-pin PCM connector. I hope I'm wording that clearly enough? If the "ground" wire for the O2 sensor just grounds to the body, (A) the PCM is not receiving any input from it, and (B) the PMC will not output any codes. I just re-read a few of you older posts and it appears that the PCM is in fact outputting codes. So I assume a couple of posts ago when you say you have "no codes", you mean other than the ones you posted earlier? If you are not getting any codes output at all then the PCM may not be seeing any input from the O2 sensor. if nothing else, you should be at least getting one code (11) for "system pass".

2: The open breather on the valve cover is ok although you are losing some metered air, but it won't make the car run like crap or not at all. in a stock setup the valve cover breather is closed with a hose that runs back into the intake before the turbo.

3: It does appear that your PCV system is hooked up correctly, though it is difficult to see exactly what valve is being used. Is that check valve mounted horizontally? Might think about taking that out and just running hose from the pcv valve to the intake.

4: In an earlier video you were running it with the VAM unplugged. If you unplug it now will it start? If it does, the VAM could very well be your problem. Either that or you have a serious (probably pre-Throttle Body) intake leak.

5: 15" of vacuum is kind of low depending on what cam you're running. 18-20" is normal. I currently get 24" vacuum at idle with a slightly bigger than stock cam. Do you have access to an air compressor? if so you should really pressure test the intake. You can buy a pressure tester fitting, but it's faster and cheaper to just make one using a PCV end cap, air fitting, and a coupler to attach it to the turbo - all of which you can get at Lowes or Home Depot. Hook it up to the compressor inlet on the turbo and pressurize the whole system to 15 lbs or so. Soapy water is great for finding leaks this way.

6: That yellow wire from the PCM connector... how many pins from the end is it? If I'm looking at lthis right, it Looks like it could either be pin 44 or 45? Hard to tell from that angle. 44 is not used, but 45 is for the BAP sensor. Can you let us know which pin it goes to or take a photo of where it goes in the connector.

I snapped a few shots of a "stock" setup on the components you showed in your last video...

This is the stock O2 sensor...
http://i798.photobucket.com/albums/yy270...G_2069.jpg

And the O2 signal return which from from the compressor housing back into the vehicle harness. from there it goes to the signal return wire and back to the PCM...
http://i798.photobucket.com/albums/yy270...G_2067.jpg

And this is the stock PCV setup the large hose on the bottom of the PCV valve runs down to an oil separator on the block. The smaller hose at the top runs directly to the bottom of the upper intake...
http://i798.photobucket.com/albums/yy270...G_2068.jpg

I don't know that these shots will help you any. Just wanted to show the stock setup.

Oh... and no one is laughing at you, dude... Trust me. There are posts on this board which are 3 pages long trying to figure out running/starting issues.

OK the car wont run now !!!! So just for fun reconnect the old ignition switch and see if it runs??? No need to mount it on the column. Plug it in and use a small philips screwdriver to actuate it. if it runs then clearly the new switch is different. Back up and get the car running.

B people make to much out of the HEGO return. Its not that critical. Some are wired to SIG RETURN and some are grounded at the BELL. I have mine on the fender apron until i install my stand alone. What has to be dun here is a whole lot of voltage checks and ground checks. Clearly something is intermittent. Either a wiring issue or a component. Either way the car should run even if the O2 is disconnected. The ECM ignores O2 signals past 2800 RPM'S any way. so if he is having issues past that point the O2 is out of the picture. If i was closer i would Diesel over their in a heart beat. We are missing something here that is STUPID. What we have to do is figure it out. From a Key board its difficult to tell. This type of an issue needs hands on. With that said he is going to have to check voltages and grounds on the 60 PIN CONNECTOR. Good luck and hang in their

HEY MIKE! I MAY be able to help you out this weekend. Contact me and we'll see if we can work out something. garry

OK, so the plot thicken's.. now it's the opposite. The car is completely horrible when cold, stumbles all over and won't idle at all. When warm, it's a bit better and can sometimes idle on it's own. Just still seems to have a heavy stumble. I THINK it's fuel-related, based on all of the ignition parts have been changed.

I just took this video to show it a bit more.
http://s9.photobucket.com/albums/a87/pay...G_0559.mp4

Well the yellow wire as far as I can tell is for the octane switch. That is pin 24 where it is originating. That would be pin 46 which is the signal return that it's connected to on the other end. With it hooked up like that, it is in "Premium" Fuel mode. Disconnecting the terminal connection on the yellow wire will set it to "Regular" fuel mode. 87-88 TC's have a switch to switch between modes. You can try pulling apart the terminals that are half way through that wire and see if anything changes, but it probably won't.

The FP won't go over the base fuel pressure (~39psi) until you get into boost. It's normal in this video.

And what made it start now? you just keep trying? did you change anything between this video and the last?

Thanks B, guess I'll leave it connected as I run 93 in the tank at all times.

I'm going to post another video in a few min's, showing how the car drives now.

After I took this video though, I disconnected the VAM and the car ran better. It was still bucking a little bit, but past 2500rpm (out of boost), it drove cleanly. I tested the VAM though with my mutlimeter and it showed fine. I'll see if I can find another one locally to swap anyways.

I noticed the biggest problem area is 1500-2500rpm. Sometimes it'll clean up past that, sometimes is won't. It's really weird.

Originally posted by B:
And what made it start now? you just keep trying? did you change anything between this video and the last?

You'll see how it start cold in this video once it's uploaded. Basically, I just kept trying and held my foot ever so slightly to keep the rpm's up till it warmed up.