a few different problems here..please look

[CMTalon]

ok first off i'm new to this forum and dsm's in general. i've tried doing some searches and haven't had much if any luck so please bare with me....the car in question is a '92 talon awd, when driving no matter the throttle position at about 4-5k the car will start to back fire and or stutter, almost stops accelerating. next is i can't seem to build more than 7-8lbs of boost. 3rd when engaging the clutch to leave a stop sign or what not, the car will almost want to die unless i kinda pump the throttle a little. i've done the basic boost leak testing and fixed a few minor leaks and also replaced bad throttle body seals. i took it down to mitusubishi for a check engine light and they came back saying they couldn't even get their system to communicate with my car (no charge ) which made me think fuses or maybe an ECU? i know i need to replace the turbo manifold gasket and there are a few minor oil leaks but i don't think that would be causing my problems. if anyone has had or have these problems please comment any help will greatly appreciated.

 

[silver bullit]

Boost leak test, check the maf and what mods are done to the car?
Is the bov venting?
Did you fix the rest of the boost leaks?
If it is throwing a check engine light check vfaq.com to make a diy check engine light reader.

If it is not charging then check your battery cables, fuses, battery voltage and alternator.

 

[CMTalon]

as of now there are no mods, i'm sure it was modded before i got it though, the guy said it was a re-build from previous owner, but no papers, for the BOV venting question, do you mean venting to the atmosphere? its set up to recirculate (stock). i did boost leak checks, but i can check again to make sure there are no more. i'll check out that diy check engine light reader. thx for your input , i'll keep this updated.

 

[kenamond]

Pressurize to 15-20psi, stop adding air, and watch how the pressure drops. If it drops quickly, find and fix the leaks. Mine drops 1psi every 4 seconds to give you an idea.

If you don't mind spending a bit more cash, you can get a logger for your car VERY cheap. The hardware is usually an old Palm which you can get off eBay for $25 or so and a cable which you can make yourself if you can do basic soldering work. The logging software is free. The logger can tell you a whole lot about the condition of your car and will read diagnostic trouble codes. So you could probably have the whole logger setup for $40 or so.

I'd check the plugs with the sputtering. You want NGK BPR6ES gapped to 0.028" ($2/ea at NAPA). Might also consider changing the plug wires.

Make sure you've got the intake air-tight, seriously consider the logger, and change the plugs and (maybe) wires.

 

[bmoha2]

PCV valve?

 

[CMTalon]

ok today my buddy will be coming over with his deal to do a boost leak test, i looked into a logger and thats sounds like it would be a good thing to invest in, what about DSM link? my buddy told me that if i plan on modding it would be good purchase, any insight? also another thought i had, i wonder if the turbo not spooling up to full boost could be a faulty boost controller? i was driving it around last night and at about 1/2 throttle around 4k the engine stuttered real hard, made the entire car jerk. so i think today after we leak test i'll disconnect the boost controller and re-route the vacuum lines and see what happens. i'll also check out the PCV valve, thanks for all the input thus far

 

[kenamond]

ok today my buddy will be coming over with his deal to do a boost leak test, i looked into a logger and thats sounds like it would be a good thing to invest in, what about DSM link? my buddy told me that if i plan on modding it would be good purchase, any insight? also another thought i had, i wonder if the turbo not spooling up to full boost could be a faulty boost controller? i was driving it around last night and at about 1/2 throttle around 4k the engine stuttered real hard, made the entire car jerk. so i think today after we leak test i'll disconnect the boost controller and re-route the vacuum lines and see what happens. i'll also check out the PCV valve, thanks for all the input thus far

My bet is a bad boost leak, but you won't know until you do the test. DSMlink is a great tuning tool, but it isn't cheap and it certainly isn't your problem. If you disconnect the boost controller, you still have to provide a boost signal to the wastegate actuator or you'll overboost (that's not a good thing). Unless you're overboosting, your stuttering problem is something else. If the boost leak test shows a bad PCV valve, replace with an OEM unit from your local Mitsu dealership (~$8); the Autozone/Carquest/etc. valves will not hold boost even brand new.

 

[CMTalon]

Did the boost leak test again, turns out the vacuum line coming off the waste gate has a nasty leak and the BOV has a leak too. Under 20psi it was dropping about 4lbs per second, also, there is some sort of line coming off of the intake manifold that has been caped off with a bolt and some washers which also has a leak. I'm not sure where it leads to, but its located on the left side of the manifold coming straight up, I would like to find out to re-connect it. I'm going for a stable stock status right now just to get her on the road. So I'll be buying a new vacuum line and clamp for the waste gate and attempt to crush my BOV, I've searched and read a few threads on this, it seems like a fairly simple task?? Thanks.

 

[KazooGS-T]

Also, you can get your computer scanned at autozone or advanced auto for free, that way you don't have to pay a diagnostics fee. They will print you a sheet that shows what the codes are and what they mean, for absolutely free!

 

[rarson]

DON'T crush your BOV! You will ruin it (whether you realize it or not).

I am on a crusade to stop people from crushing BOVs. Why? Because they work so well when they are not crushed.

First of all, a non-crushed BOV should hold about 19 psi or so. If you're not running that much boost, you shouldn't be worried about modding the BOV to hold boost. Secondly, realize that when you crush the BOV, you are essentially modding the spring rate of the BOV. You are taking that fine-ass 1g BOV and turning it into a cheap, tight Greddy which you can't adjust. Yeah, it might hold more boost, but only because the spring rate is higher.

Instead, you could modify the BOV properly to hold the boost you want it to. Take the BOV off and look underneath it. See that little hole on the flange? That hole runs up to the underside of the diaphragm. It sees boost pressure whenever your intake pipe is pressurized. So if the top of the diaphragm is seeing boost pressure, and the bottom of the diaphragm is seeing boost pressure, then what is holding the BOV shut? The spring... hence the reason why so many people crush their BOV's.

But the actual problem isn't the spring, the problem is that the bottom side of the diaphragm is negating all the boost on top of the diaphragm. So the sensible solution is to block off that port and open it up to atmosphere. It's a fast actuating port (the pressure on the bottom of the diaphragm is meant to help shoot the BOV open as fast as possible).

You can either block the hole off (set screw, JB Weld, whatever) and drill a hole on the side of the BOV, or mod it ala Dejontool (DEJON | Powerhouse which is basically the same thing, except you're adding a boost source and a method to either use it or not), but either way you'll end up with a better solution than crushing, without ruining the great characteristics of the valve.

Sorry for such a long rant, I hate to see people crush perfectly good BOVs.

 

[rarson]

I forgot, here's another link about BOVs: DDG- Talon BOV mod for HIGH BOOST

 

[CMTalon]

Oh wow, I had no idea crushing was such a bad thing, thanks for the tip I'll look at some of these alternative methods to get it hold pressure instead. I was gonna go down to the Auto Zone for the engine codes, but I called a Schucks first and they told me that my car was too old for their tools, so I assumed (I know never assume ) that Auto Zone would tell me the same thing. I did however take it to my local Mitsubishi shop and they came back saying that their system couldn't communicate with my car, first they tried the cigarette lighter, nothing (probably bad fuse), then they connected it to the battery?? I don't know what all happened because I wasn't there. After leaving the shop I thought that maybe its a bad fuse or possibly the ECU.

If you don't mind spending a bit more cash, you can get a logger for your car VERY cheap. The hardware is usually an old Palm which you can get off eBay for $25 or so and a cable which you can make yourself if you can do basic soldering work. The logging software is free. The logger can tell you a whole lot about the condition of your car and will read diagnostic trouble codes. So you could probably have the whole logger setup for $40 or so.

So I'm going to do that so I can get my own codes

 

[kenamond]

There is a tradeoff with the "Dodge garage mod" of the 1g BOV. That boost signal on the bottom of the BOV that pushes up on the diaphragm helps crack the BOV valve loose when the IM pressure drops. That's the "quick release" feature of the 1g BOV. If you do the DDG mod or block that port on the bottom of the BOV, you lose the quick release. I'm not sure what consequences that has, if any, but I'll speculate that it might delay the boost bypass enough to get some compressor surge in some situations. I honestly don't see what's wrong with slightly crushing the BOV. Sure, you can overdo it and ruin the BOV, but crushing it a bit will help increase peak boost. If you have any boost spikes and are trying to run 17psi, you might trigger the BOV which will kill your boost performance. Crushing it a bit to increase the cracking pressure to 21 or 22 wouldn't be a bad idea IMHO. So you get to pick the lesser of two evils with the 1g BOV mods. I think that crushing is less evil.

Can you post a picture of that line from the IM that's capped?

And I think Autozone can only read OBDII-equipped cars (2g). We 2g guys get free code reading but $125 loggers. You guys get $25 loggers and no free code reading (I think you guys win that contest).

EDIT: Link for making your own 1g logger cable is below (from the Palm n Stein website):
Palm n Stein 1g Cable Page

 

[slow4g6392tsi]

I don't know if your ECU is modded or anything but I know when I bought my Eprom on craigslist all I was told it had was injector compensation for 550s which I also bought. Then I found out it had a 5500 rpm stutter box which I like but it was also wired incorrectly for no lift to shift at 6000 rpms and it would stop their whether the clutch was disengaged or not. What kind of clutch is it? But it sounds like your problem was already solved and just needs to be fixed.

 

[CMTalon]

Awesome, thanks for that link, yeah I can go and get a picture real quick

As far as I know the ECU has not been modded, I bought the car from a kid last October and he told me the previous owner had done a rebuild on the engine. But the car does show signs of being modded at one point in time, probably hence the re-build? As for the clutch I have no idea whats in it, judging by how it drives and shifts I would say a OEM or equivalent.

<a href="http://s224.photobucket.com/albums/dd268/CMTalon/?action=view&current=IMleak.jpg" target="_blank"><img src="http://i224.photobucket.com/albums/dd268/CMTalon/IMleak.jpg" border="0" alt="IM Line Leak"></a>