Need a 1g DSM turbo expert

Got a question that I was wondering if anyone could help me with. I'm having problems with the Turbo on my Talon, and while I know a fair amount about automobiles in general, I'm rather new to the turbo game. I have a 91 TSi 2.0 FWD Talon and she's acting like a pooch. If anyone can help, I'll be forever in your debt.

Originally, I was having a problem whenever the turbo would kick in. Anytime the turbo guage got above zero, the car would start to lunge and jerk. Kind of like the way a car does when a new driver is learning to drive stick. Whenever the boost isn't kicked in, she would run fine. But, the minute I got above manifold pressure, that's when the trouble started. Also, the idle was rather rough, especially after being driven for a while.

It was recommended that I search for a turbo system pressure leak. I have yet to do that, but I did find a vacuum leak on the line that hooks into the BOV. I fixed that, and now this. I'm not sure if I fixed one problem and this is another, or if this problem is just a different symptom of the same problem. Maybe a turbo leak causes this, too.

Okay, here's what's happening now: Instead of jerking and lunging, now the turbo won't even kick in at all. Well, barely, anyway. When I accelerate, the turbo guage stops at about 2 or 3 pounds of boost and will go no higher. When I'm driving, she runs fine, just no boost.

Also, idling is a huge problem. After driving for a while, anytime I approach a stop and disengage the clutch, she dies. When I try to start her, she doesn't want to fire unless I push the accelerator. If I feather the gas, she'll stay running, but dies if I don't.

One final thing of note and I'll stop this book. Sometimes when I try to start her after not driving her for a while, she doesn't want to run at all. She'll fire, but die immediately. Nothing helps this, except persistence. Feathering the gas doesn't make her run. If I keep the starter engaged, which I know is a horrible thing to do to a starter, she'll run, but dies as soon as I disengage it. After being persistent and restarting her dozens of times, eventually, she'll run, but then she runs like shit, doing what I told you about above.

If anyone can help, you'll be my hero!

Thanks
Jon

P.S. Don't get too technical on me. You don't have to put it in "Turbo for Dummies" terms, but don't go overboard. Like I said, I'm new to this game.

I dont mean to offend you by asking this, but what type of plugs are you using, what is thier condition, and what is the gap set to? Wires? I'm sure you covered it, but I have to get the simple things out of the way. Additionaly, wether or not a boost leak is causing your problems, check for them and fix them all. Every car I've ever tested had leaks. 1G especially since they are older. There is no point in trying to diagnose any of the symptoms you mention until the ignition system and intake integrity is up to par.

So a quick overview, when ever possible, use NGK BPR [6 or 7] ES plugs only, gapped to 028-030, with stock or NGK wires. This is the known good combination, anything else you try may be "new" but may not work.

For boost leak tester see the instructions at www.vfaq.com, in the "intake" section.

Hope that helps. Once you get those things done, let us know if there is any change. If its fixed, drive it on. If not, we can start to look further into it.

i had laser rs 91.when i firs get it they sad the turbo was bad,wouldn't go over 2-3 psi on the gage,but when not pushed the car was idelling and driving ok.
wasn't bad turbo ,only from vibration the metal stick right in front of the turbo was disconected(i dont know the name of that metal stick-somebody help-just know that that stick opens the turbo valve or whatever upon the high RPM.its right up front turbo).2 min and i was flying.thats the first time i drove turbo.so u can check yours too,looks like it's connected and is actually not.also about the startting.u know the coil-where your wires go.that thing is supported from a 4wire cable that has an outlet holding for the engine(if the stand or outlet broken)its kind of a plug (male-female)which can be loosening inside means,not having the plug making full contact(ellectricity)goin to your coil...the thing where your wires plug into.from the time and engine shake that thing was loosening in my old turbo.hope it helps

That is the wastegate flapper arm, and the rod is from the WG actuator. It is fairly common for that cotter pin that holds it on to rust and break on 1Gs.

hi, Jon , was up dude.
did u check your wastegate actuator? mine was disconected coasing the turbo not boost more than 2-3 psi on the gage inside. also check your turbo if its good at all, check the shaft play, but i doubt its goin to be the turbo. alright, let me tell u about the rough idle and not wanting to start sometimes -my "lucky" experianse.
after i find out that my WG actuator (WG-wastegate) was not conected and before that, the car would go into a possition where it has a rough time idling. i mean like the motor starts shaking and feels like the car works only on 3 cylinders. it wouldn't do it all the time only sometimes when she was feeling like it. oh boy, thats what happend one "beautifull" day on my way from houston(TX) to saint petersburg(FL).(i used to work all the way in houston so i was making constantly trips back and forth).
i was driving half way,cruise on ,75 mile/hour, just past alabama/florida boarder and there the car starts act funny. the same filling like only 3 cylinders are working properly. ho well it wasn't the first time so i keep on going right. maaan i past about 50-60 miles and a second cylinder died. very tough for the car to run on 2 cylinders, somehow i could get myself to the next exit, a WALMART supercenter. i tough it was the spark plugs , so im getting a new ones, wrenches some tools ,changed them and the car seemed to get back to normal. but only for a while. i drove the next 350 miles on 3 cylinders,maan i was so happy when i got home. so after this accident i was commited to find out what the fuck was wrong with the car.it was about 7-8 months since i had the car, it was coming on and off and it wasn't bothering me ,but after the last accident on the long road trip i could no longer afford this to happen.and i was supposed to drive back to houston after a few days so no way i was getting stack somewhere on the road by myself.
there is when i got lucky. finnaly i find what was coasing that long ass problem of my car. u know that is the coil pack ,right? my problem was bad spark plugs or cables or anything common else. it was the coil pack supply plug (the male-female conectors with 4 wires). its located right behind the intake cam gear. after i unplug it everything seemed to look fine, but wrong again. the problem was that the female adaptor wasnt conecting with the male adaptor corectly. the male adaptor has 4 "sticks" inside the plug, and the female has 4 "holes". so the male "sticks" get into the female "holes" after u conect both plugs. the problem was that from the time or whatever the female "holes" were too loose, not letting the male "sticks" to make a good conection on the walls of the "holes". i simply bend the male "sticks" so they dont go strait in without touching the walls of the female "holes". did u get where i'm going? hope that help .
send me back after u check that out, and in general the car is 10-12 years old, i would check every electrical plug and make sure the above is not happening.just make sure all your plugs ,wires, and cables are conected and make good CONTACT. they might seem connected , but like i sad , inside they might not make good conection.
i realy hope u fix that problem soon, and check all your vacum lines...

Quick update for anyone who cares. I think I've gotten to the bottom of the hard start problem. Pulled a plug and it was ridiculously black and sooty. Looks like the black smoke and unburnt fuel spitting out the tailpipe was caused by the car running too rich. Fouled the plugs out. I replaced them, and it fired up, no problem. But, it's still running crappy, so I still need to diagnose the turbo problem. I'm going to try and look for a boost leak tomorrow.

Question: Does a boost leak cause the computer to alter the fuel/air ratio? Would a leak cause it to run to rich? If not, how about the MAF sensor? It took a hell of a hit in the accident. If anyone can help with that, I'd appreciate it.

Thanks again.
Jon

go read your other thread i posted it there!

Here's another update. I did a lead check on the turbo system last night. Haven't checked the MAF sensor as of yet. That's my next order of business. Wanted to ask a question before I move on. I wasn't able to check all of the lines in the turbo system for leaks. Reason for this was because I couldn't get the system to pressure up long enough. I've never done any of this, so I'm not sure what's supposed to happen. Whenever I'd pressure the system using my air bubble, I'd hear a hiss from the valve train for about five seconds. Then, all of the pressure would be gone. If I took off the oil filler cap, the noise would get louder.

Now, I'm not sure what this means. I'm guessing that what I'm hearing is the air leaking into the cylinders through whichever valves are remaining open when I shut the car off. Is it supposed to do this? If not, what can I do to stop this?

Thanks again to all who read this. Any help I get is greatly appreciated.

Sincerely,
Jon

Sorry, guys. Should've clarified just how I tried to pressure test the turbo system. I took off the outlet hose (the one between the turbo and the intercooler) from the turbo system and put a PVC cap in the hose. I drilled a hole in it and put a valve stem in it. I used an air tank to pressurize the system. I wasn't able to check the hoses, intercooler, BOV, and the like for leaks because I couldn't get the system to stay pressurized. Within seconds, I'd lose whatever pressure I put into the system through the valve train. I could hear the hiss for a few seconds from under the valve cover, and it got louder when I removed the oil filler cap. Not sure why this happened. I'm guessing that I lost the pressure through the valves that were open when I shut off the car. But, is this supposed to happen? Like I said, I'm new to this and I've never done anything like this before.

Thanks again, fellas!
Jon

Okay, guys, time for a further update. I came to a revelation last night. So, today, I'm putting the boost leak check on hold. Remember when I said that after I changed the plugs, I got her to run, just not very well? Well, last night, I started her and tried to take her for a spin. I couldn't get her to go anywhere. She would not stay running. So, I took the suggestion of more than a few people and I disconnected the Mass Airflow Meter (the one in the air cleaner cannister). While I was at it, I disconnected the battery for a few minutes to reset the computer, thinking maybe that would reset the fuel/air mixture. When I reconnected the battery and started the car, it ran. Not very well, but it ran. So, I'm thinking, "Cool. I just reset the fuel air mixture", and took her for a spin, albeit a very rough spin. I drive a few blocks, then pulled over to reconnect the MAF Meter. I popped the hood and reconnected the plug, then tried to restart her. I was right back where I started. She wouldn't stay running at all. She'd fire and die instantly. So, I disconnected the MAF Meter, and drove her back home.

Here's another oddity of that situation. I replaced the Idle Speed Control a couple of months ago because it was chattering at me like a chipmunk when the key was on but the car wasn't running. I was thinking that was the reason that she was running so crappy. That didn't fix the problem, though. The new one I put on still chatters. Well, I hadn't noticed at the time, but last night when I disconnected the MAF Meter, the ISC stopped chattering. When I plugged it back in, I noticed that the chattering had been gone and came back when I plugged the MAF Meter back in. So, after a series of disconnects and reconnects of the MAF Meter, sure enough, whenever it was unplugged, the ISC was quiet. Whenever it was plugged in, the ISC went crazy.

So, what does that sound like to you? MAF Meter's bad, right? Couldn't just be caused by a vacuum leak, could it? I'm going to alleviate any possibility of that tomorrow. I'm going to go buy a spool of vacuum line and replace all of them. Not just because it's running bad. After 13 years, I'm sure it'll do the car some good. I'm going to go to my donor car today and grab the MAF Meter off of it. Not sure if that'll fix it, though. The reason I say that is because the outer housing of the air cleaner cannister on the donor car is missing. So, that MAF Meter has been blowing in the wind for God knows how long. I'm sure that one's bad. But, for free, it can't hurt to give it a go. If anybody has any other ideas for me or wants to confirm my suspicions, I welcome any comments. I'll keep you posted as to what I come up with.

Thanks for everybody's help.
Jon

I'm not going to be updating this post any longer. It's rather old, and some people are getting upset about the presence of multiple posts about what is essentially the same problem. I am, however, going to keep three identical posts for the three types of cars that are essentially the same, those being the Laser, the Eclipse, and the Talon. So, if you have any questions for me or want to offer any help, can you post it to one or all of the following posts:

Laser: http://www.automotiveforums.com/vbulletin/showthread.php?t=231451
Eclipse: http://www.automotiveforums.com/vbulletin/showthread.php?t=231452
Talon: http://www.automotiveforums.com/vbulletin/showthread.php?t=231450

I appreciate you checking this post, though. If you've got any help for me, write it up on one of those other posts. I'll get it that way.

Thanks again for helping me.
Jon

Okay, we can close the book on my problems, once and for all. I've finally gotten my Talon back in working order. Turns out my problems were twofold. I ended up having a bad turbo and a bad ECU. Replaced the turbo first, and that got rid of the jerking. It was still running rich, though. Then, over the course of the last few days, I came to the conclusion that my ECU was shot. So, yesterday I pulled one out of another car and put it in. She started right up. So, I'm rolling again, and it's in no small part to all you guys that helped me out on this website. Thanks for everything. You guys saved me.

Jon