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**NOT RESOLVED**Randomly losing cylinders/dying**NOT RESOLVED**

5OF2k

Well-known member
Joined
Mar 28, 2012
Messages
664
Location
colorado springs, colorado
Good morning!

First off:

stock 2.0 bottom end
272 cams
evo pink 560s
SD setup
AEM EMS
Magnus SMIM
OBX ramhorn
Full-Race T67(12psi)
7ES(and 6ES) plugs gapped to .23(NEW)
NEW Denso Wires
known good 2g Coilpacks
ICM less than a year old
CPS less than a year old(replaced same time)

My car was out of comission for about 5 days when my clutch master went bad. When I replaced it, the car acted a bit funny on startup and idle until it warmed up, then was good. I took it out, drove it around, and beat on it a little bit without issue. I then drive to my parents house and hang out for a while, come back out to go home and the issue starts:

RANDOMLY will lose cylinders. When I say lose, I mean not firing. I'll have to floor it to keep it running, and it sounds like it's running on 2 cylinders, barely. Literally driving along, smoothe as glass road and BLAM, falls on its face and I have to turn off. It did it that ONE night when I replaced the clutch master, and then stopped so I didnt think anything of it.

Fast forward to Monday morning. I wake up to go to work and the car doesnt want to start;the starter sh*t on me. So, I call into work, and call a buddy to take me to get a new starter and stuff like that. I replace the starter, and if fires right up, like a champ. I let it run for a while, make sure everything is good, and leave to take the starter back to the parts store for my core charge. I never make it(in my own car, that is). Car does the cylinder loss/die thing on me easily 6-7 times in the course of my 2.5 mile drive from my GF's house(where I was replaceing the starter) to my house(as far as I could make it on 2cyls).

So, I get to my house and pull the plugs, and they are BLAAAAAAACK fouled, and I also notice I have a leaky injector(#1). I mean BAD, and wet, fuely all 4plugs. Now, I find it a bit odd, because just that previous sunday I was at the shop and pulled them out, re-gapped them, and threw them back in. Just that day before they were perfect. Good burn, good timing, no signs of detonation, nothing. Perfect.

So, I call up my pops who luckily wasnt working Monday, and had him take me to drop off the core and get some new plugs(I bought 2 sets, just in case). Head to my house and throw in the new plugs, replace the injector o-ring that was ripped and fire it up. At first its not wanting to idle, running on 2cyls, and smoking like it was before. So, I give it gas to try and clear it out. It eventually clears up, so I let it idle for a while. it dies.

I crank it over and fire it up again and it's fine, good to go like nothing is wrong, so I head off to my parents house. On the way there, Im driving normal and decide to beat on it a little bit, and it goes fine, runs good until I'm decelling for a traffic light. I go to get back on the gas and nothing, dead. So, I pull to the side of the road and try starting it again, and it wont do anything unless I keep it floored, and at that point it sounds like ONE cylinder and it's barely spinning at 500/1000 RPM. Eventually clears up, so I take of again and guess what, it does it again, 3-4 times. This time, I just keep it floored because Im pissed, and it keeps cutting back and forth from all 4 cylinders to 2(or however many).

finally make it to my parents and check things out, looks like the fuel leak I had was drippin down onto the coils/that area, so I start calling around for another set of coils. Find a set of 2g coils so I went and picked them up.

I go to install the coils, and notice the wiring for my stock coild is a bit shotty. The coil side connector has the insulation for the wiring coming off in a few spots. I figured the problem was that, so I decide to replace it with the 2g wiring that came with the coils(verified the pins and wiring was the same physically, NOT in color). Slap the coils on my bracket, re-mount the bracket, and plug everything back in. Fire it up and it's running a bit off, but clears up almost immediately. So, I let it run for about 15 minutes at idle, and its fine. THe whole time Im under the hood wiggling connectors and harness and everything trying to get it to act up again, and NOTHING. So, I take it out and drive it a bit. Put about 10 miles on it, no problems. Some driving nicely, some "spirited".

So, I figure SWEET! I got it!

Wrong.

I go to leave my GFs house this morning, and it fires right up, idles great, and is warming up while I scrape my windows. I hop in, and it's just about warm, and I take off driving to my house to change before work. I get stopped at a light, and BOOM. Dies. So, I go to re-start it, and it re-starts, but on 2CYLINDERS, smoking, and everything as above. CLears up, boom dies again, and so-on and so-on and so-on. It does it about 6-7 times at that ONE light, and I take off driving towards my house. Make it about 2 miles before Im stopped at another light and boom, dies again. another 3-4 times of it cutting in and out, dying, smoking, clearing up, and so on before the light turns green and I take off. It's running on 2cyls the whole time at this point, all the way through my comples and to my garage about 1/2 mile from the last stoplight.

So, I pull in the garage, pop the hood open quick and pull a plug.

FOULED.

Just as black and wet as the plugs I had pulled out Monday afternoon, and these are NEW plugs I JUST got.

Now, Im a very capable mechanic and have done it for a living for almost 15 years now, but cant get it to act up or duplicate, nor am I able to diag anything when it's acting up(because I have to stay in the car giving it gas for it to stay running). Im at a loss, it's like a catch 22!

I did notice when it;s running on 2cyls, it's making boost....which is weird. Especially with the T67. I mena, on my 16g I could see that because just revving the car makes boost, but it doesnt on the T67 typically, especially not the 10psi it's making when it's misfiring/dropping cylinders.

I dont know what that has to do with anything, but yea, it's interesting and worth a mention I suppose.

Anyway, thanks for reading, and thanks in advance for any suggestions. I really need to get this figured out and sorted; it's my ONLY vehicle and already costing me money by me not being able to drive the ~20 miles I have to, to and from work.

HEEEELLLLLP!!!!

-Jake
 
Last edited:

EHmotorsports

Well-known member
Joined
Sep 25, 2012
Messages
1,278
Location
Beaverton
If the car is fouling the plugs on the same two cyl's swap injectors to the opposite banks. What is the fuel pressure at when this happens? Things that can cause this are Cas not giving a proper signal to the ecu, ignition control modual faulty, pressure regulator going out causing high fuel pressure. Just need to use the basics of diagnosis to figure out the problem. My guess is its ether the Cas or wiring to it, or the ignition modual. But this is purely a guess until proper diag is completed.
 

Swap injectors to see if you can duplicate the problem but on different cylinders, if not, remove ECU and check for bad cap/ burn spots and this sounds ALOT like bad transistors in the ECM for spark. Also make sure your ground cables and good and clean
 

5OF2k

Well-known member
Joined
Mar 28, 2012
Messages
664
Location
colorado springs, colorado
Quoting EHmotorsports:
If the car is fouling the plugs on the same two cyl's swap injectors to the opposite banks. What is the fuel pressure at when this happens? Things that can cause this are Cas not giving a proper signal to the ecu, ignition control modual faulty, pressure regulator going out causing high fuel pressure. Just need to use the basics of diagnosis to figure out the problem. My guess is its ether the Cas or wiring to it, or the ignition modual. But this is purely a guess until proper diag is completed.



I hear you, I really do, but both the CAS ICM and the pigtails for both are less than a year old and OEM. Fuel pressure is at 41 psi(what it's been at for over a year now).

Also, all four plugs are fouling, not just 2-3(like I wish were the case).

I need to see if I can find another known goos CAS and ICM local I suppose, give it a shot and see what happens. Also need to connect to a laptop and log.

Appreciate the replies, fellas!

-Jake
 

EHmotorsports

Well-known member
Joined
Sep 25, 2012
Messages
1,278
Location
Beaverton
if you were closer i would just take the one out of my galant and see if it works.
 

5OF2k

Well-known member
Joined
Mar 28, 2012
Messages
664
Location
colorado springs, colorado
Appreciate the thought man, thanks!

-Jake
 

prove_it

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Joined
Jul 3, 2008
Messages
4,201
Location
Sioux Falls, SD
This is my opinion:

Sounds like your addressing a whole engine fault, which in my opinion would put the CAS and ignition down the list. Doubt it's an injector issue as it's affecting all the cylinders. It's a random failure and that would tell me that it's unlikely to be a mechanical issue. The fact that your "spooling" up tells my that your probably just dumping fuel into all cylinders which can ignite post chamber and cause the turbo to spool, think old school antilag. You could be losing spark too, but honestly how often do coil packs and CAS fail randomly after only a few years old.

My theory:
It's getting a faulty signal from either the coolant temp sensor for the ecm, MAP or O2 sensor.

If the coolant sensor was reporting a -40 temp at the time, the ecu will richen the piss out of it and cause these same issue.

I see you have an AEM ECU, go out and try to datalog the event. You can then check all your sensor readings and see if the computer is at fault or not.

 
Last edited:

5OF2k

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Joined
Mar 28, 2012
Messages
664
Location
colorado springs, colorado
"This is my opinion:

Sounds like your addressing a whole engine fault, which in my opinion would put the CAS and ignition down the list. Doubt it's an injector issue as it's affecting all the cylinders. It's a random failure and that would tell me that it's unlikely to be a mechanical issue. The fact that your "spooling" up tells my that your probably just dumping fuel into all cylinders which can ignite post chamber and cause the turbo to spool, think old school antilag. You could be losing spark too, but honestly how often do coil packs and CAS fail randomly after only a few years old. True, but it could be a timing issue as well. And while I hear you about the dumping fuel thing, it's not poping like anti-lag or anything like that, and no backfires, it's just misfiring. Would that still make sense?

My theory:
It's getting a faulty signal from either the coolant temp sensor for the ecm, MAP or O2 sensor.That could be, unfortunately I have no way of connecting to the ECU being as I use a borrowed laptop from a friend, and that friend picked up a work schedule EXACTLY opposite of mine. I havent been able to hook it up to log in a month or so because of that. Hopefully I can find another one to use or something, because loggin definitely would help.

If the coolant sensor was reporting a -40 temp at the time, the ecu will richen the piss out of it and cause these same issue. I wondered that kind of too, but then I figured it would be the typical 15 minute trying to start ordeal as is normal of the typical DSM coolant temp sensor ordeal. Also, this car is using an GM style temp sensor, MAP, IAT, and so-on, if that has any affect on the outcome, I have no idea....? Im still somewhat new to AEM, really

I see you have an AEM ECU, go out and try to datalog the event. You can then check all your sensor readings and see if the computer is at fault or not I'll go and see if I cant find another laptop to log with, see what's going on. Typically, AEM boxes dont go bad. It's fairly unheard of from what I've been told by my tuner. BUT, I suppose it's just like everything else; always an acception!"



Edited with my responses. Some good points to consider, thank you!

-Jake
 

prove_it

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Joined
Jul 3, 2008
Messages
4,201
Location
Sioux Falls, SD
The popping of anti-lag is from retarding the timing. I was referring to the old school fuel injected manifold concept. Back in the days when there was literally a fuel injector injecting into the manifold to create combustion to spool the turbo.

Yea I'd say get a laptop and check, swapping parts might not get you too far, as I'm sure that's how your feeling now. Did you get the AEM version 1 or 2? As far as I know they are pretty stout and usually don't fail.

Good luck and from one tech to another: KISS. Keep It Simple Stupid. lol
 

5OF2k

Well-known member
Joined
Mar 28, 2012
Messages
664
Location
colorado springs, colorado
"The popping of anti-lag is from retarding the timing. I was referring to the old school fuel injected manifold concept. Back in the days when there was literally a fuel injector injecting into the manifold to create combustion to spool the turbo.{b] that's a good point, I just figured fuel igniting in the manifold would make some sort of noise lol[/b]

Yea I'd say get a laptop and check, swapping parts might not get you too far, as I'm sure that's how your feeling now. Did you get the AEM version 1 or 2? As far as I know they are pretty stout and usually don't fail. yea, that's true. BUT, being as I've been stuck trying to figure it out by myself at my house with next to no tools/resources at my disposal, it's kind of where Im at with it. Dammit. It's the V1 box, and yea, they're very stout. I love it so far, really. And in all honesty this is the worst break-down the car has had in the little over a year and 17k miles I put on it, so I really cant be all that upset......well, ok. Maybe I can....

Good luck and from one tech to another: KISS. Keep It Simple Stupid. lol words to live by..... again, dammit"

Thanks man!

-Jake
 

prove_it

Well-known member
Joined
Jul 3, 2008
Messages
4,201
Location
Sioux Falls, SD
Did you check for a soft set connecter? Maybe you bumped one loose that's just barely pushed together when you did the master cylinder.
 

5OF2k

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Joined
Mar 28, 2012
Messages
664
Location
colorado springs, colorado
Yea, i sure did. Yesterday after i switched the coils i had it running and shook/wiggled/pushed and pulled on every connector in the bay.

Good news is, i may have found a used known good transistor, and my GF is going to see if i can use her brothers' laptop to do some logging and stuff like that.

Now, its just a matter of getting everything in my hands!

Appreciate the replies, as always!

-Jake
 

5OF2k

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Joined
Mar 28, 2012
Messages
664
Location
colorado springs, colorado
I'll look into that!

It's just odd to think that it'd be something tune related with it popping up all of a sudden like that, AND being intermittent. But, I'll take a loos when I get it on the laptop this afternoon!

Appreciate it!

-Jake
 

desant78

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Joined
Jun 23, 2010
Messages
732
Location
Clarksboro, NJ
+1 for coolant temp sensor. It was rough to start, and when the car was fully warmed up, my 20 year old wiring randomly would lose connection (which I logged) and at the same time I started to misfire badly. I lost power, but it never turned off, then again I'm running a 16g with 560's and a keydriver chip. Maybe this issue with AEM is handled differently? If you can't get a laptop verify the leads to the coolant temp sensor isn't damaged, or a loose connection.

Good luck!
 

5OF2k

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Joined
Mar 28, 2012
Messages
664
Location
colorado springs, colorado
It isnt hard to start though, it fires right up! It'll die after it's idled for a bit, or lose power to xx cylinders while driving. if I werent moving it'd die too, I'm sure.

I'm definitely keeping it in mind as a possibility though!

-Jake
 

DynastyLCD

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May 12, 2006
Messages
761
Location
Harwinton, CT
Jake, i had this similar problem with my grey 1g a few years ago. i've had this happen also to my blue 1g. every single time, coil pack or transistor pack (whats mounted under the coil) it would drive MINT like nothing was ever wrong, boost it once or hammer on it, sometimes even just pull away from a light, same deal. misfiring and running like garbage. pull over, shut it off, start it up, drives fine.

if you had a CAS type issue, typically it won't let you rev well at all, tach jumps around, etc. or it just won't start.

i'd recommend trying another coil pack and transistor, one at a time to verify where your root problem is.

good luck buddy!!!
 

strokin4dr

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Aug 30, 2005
Messages
2,770
Location
Savannah, GA
I had the same problem before. A new ignitor solved the issue. Took me a while to figure out.
 

5OF2k

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Joined
Mar 28, 2012
Messages
664
Location
colorado springs, colorado
Thanks Phil, appreciate the reply!

Ive got a new set of coils on the car currently, and today got myself 2 known good ICM/Transitors. Threw a new set of plugs in it today with the one of the "new" transistors and it popped right off, just fine. So, i started poking around under the hood again with it running and wiggling connectors and came accross the CAS plug(which, believe it or not, has brittle, worn, and otherwise less than desirable wires on it)and give it a shake and BOOM, dies. So, i try to restart it and its doing the subaru/2cylinder thing, so i turn it off and push the wires down toward the sensor and boom, fires right up. So, i head outunder the hood again and pull on the wires again and BOOM, dies again. Go to restart and sure enough: subaru/misfire/etc.

So, even though i STILL havent come accross a laptop to do any logging, i think i may have found the problem. How i didnt come accross it the last time i was under the hood pushing, pulling, shaking and tugging everything in there, i have no idea.

Anywho, i have a good pigtail i'll be splicing in tomorrow, and ill try and snap some pics along the way as well!

Thanks to Ryan and everyone else that replied so far too. It definitely helps to get outside perspective.

-Jake
 
Last edited:

Racah15

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Aug 28, 2012
Messages
315
Location
Colorado springs CO
Hey man don't be afraid to ask for help locally. Give me a holler if you need any help. I may not know too much but 2 people checking it out is sometimes better than 1. I have a laptop and ignitors, CAS, and other goodies. I even have a 90' we can try (has it's own pigtail)
 
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