1990 mitsubishi GSX leaking and other issues

[teknicalissue]

Hello, i just purchased a 1990 Mitsubishi GSX with 260k miles for 1600. I don't know too much about cars but i'm still learning (just sold my b16 honda del sol).

The owner had said the he rebuilt the motor approximately 15,000 miles ago so there are no issues with that.

the owner also said that the slave solenoid might be leaking and that was about it.

Turns out i think the transmission is going bad (it grinds every time i go to 3rd) so it has its issues, but overall its running quite well.

Im a noob to dsm and even more of a noob when it comes to checks and maintenance. There is a leak (looks and smells like burnt oil) on the bottom of a car after its been ran. I just replaced the oil and i checked the dip stick and its definitely not burning oil. the oil seems to be coming from the oil pan but i'm not too sure why its dripping burnt when it isn't burnt.

Last but not least the car has little sputters (running at 12psi) and the headers tend to glow red after i run the car hard. I researched this and came to the conclusion that i may be running too lean/rich.

also i put the car up in a lifter and noticed that two brackets under the car that look like U's with black plasticky stuff (not the exhaust ones) that i don't know their name, are in really bad shape. I later figured out that because of those, my car makes a slamming noise on the bottom (center of the car) if i shift normally (i have to shift slowly)

I honestly don't know where to start or where to look for more issues, please advice.

although it has all of these issues, this is the greatest car i've ever purchased

 

[eurytopic]

Oil leak may be the oil pan. Try to clean it up and put some dye in the oil and check it out.

Glowing manifold is probably due to a lean condition probably caused by a boost leak. Do a boost leak test.

Black plastic things are carrier bearings. There is a cheap ghetto fix with glue, or you can take the drive shaft apart and replace the bearings.

 

[DSM1G90]

Ya, pull the pan plug out and put on a new copper crush washer. Is the pan all banged in from being bottomed out by someone hitting barricades or hopping ditches?. If there is a sharp crease in the pan, one can spot torch it with bronze to seal the leak and you can leave the pan on to do the bronze spot.

But, should trace the oil dripline from the motor to the pan, for it could come from the top end like a head cover gasket needs replacing..

Do a tranny fluid changeout with Redline MT-90 synthetic and see if that will settle down that 3rd gear grind - it may not, but at least new fluid will help it out some.

Good luck - DSM

 

[teknicalissue]

thanks for all the advice, im gonna do all of these things over the weekend.

Something else i should probably mention, the owner of the car said that it had been sitting without being ran for 2 years.

I think im going to have to get new carrier bearings because the metal is bent and it isn't in a good shape at all.

as for the oil pan, yea there were a few dents, but nothing catastrophic.

can i find oil dye in my local auto parts store?

when i bought the car, it was running on 20+ psi (had a HUGE sputtering issue) the turb was the 14g and everything was completely stock, so i lowered it back down to 12 and it fix the sputtering issue by a lot.

on very good news, i bought me some STP fuel system cleaner and that almost 100% got rid of the puttering, theres still a little here and there but it barely there.

one last thing, the car takes forever to turnover when its cold, i have to crank it for 6 to 10 seconds for it to start, what could that be? i know it has a 255 walboro fuel pump in it and many people say it could be the pump going bad

 

[XiKeiyaZI]

If it has a 255 Wally in it, then you need to be sure that you have an AFPR. If you don't then the stock regulator will quickly fail and will then cause an issue.

There are two likely issues for the oil leak. 1 : It could be the oilpan gasket going bad. 2 : It could be that the oil return line that runs from the bottom of the turbo to the oil pan is cracked at the flex section. This is a common issue with these vehicles and can easily be fixed by replacing the line all together, or taking the line out, cutting the flex section off, and then reconnecting the two pieces by use of a rubber hose to take the place of the flex section.

With the vehicle as it is, you should remove the MBC all together, and make sure you keep your mods updated so as we know what you're working with. You need to invest in a boost gauge if you don't have one, confirm the fuel pump, invest in an AFPR if there isn't already one, and soon looking into ways to log. You should also focus mainly on determining where the lean/rich issue is coming from. Make sure to perform a proper boost leak test.

By the way, as you said the car has sat for 2 years, have you changed the timing belt? That is something that shouldn't be toyed with or taken a chance on. If that breaks while you are "running it hard" then get yourself ready for a head rebuild.

 

[teknicalissue]

If it has a 255 Wally in it, then you need to be sure that you have an AFPR. If you don't then the stock regulator will quickly fail and will then cause an issue.

There are two likely issues for the oil leak. 1 : It could be the oilpan gasket going bad. 2 : It could be that the oil return line that runs from the bottom of the turbo to the oil pan is cracked at the flex section. This is a common issue with these vehicles and can easily be fixed by replacing the line all together, or taking the line out, cutting the flex section off, and then reconnecting the two pieces by use of a rubber hose to take the place of the flex section.

With the vehicle as it is, you should remove the MBC all together, and make sure you keep your mods updated so as we know what you're working with. You need to invest in a boost gauge if you don't have one, confirm the fuel pump, invest in an AFPR if there isn't already one, and soon looking into ways to log. You should also focus mainly on determining where the lean/rich issue is coming from. Make sure to perform a proper boost leak test.

By the way, as you said the car has sat for 2 years, have you changed the timing belt? That is something that shouldn't be toyed with or taken a chance on. If that breaks while you are "running it hard" then get yourself ready for a head rebuild.

Awesome advice, i never got this much attention from Honda tech

i don't think i have an AFPR, where would it usually be at? (nub question i know).

i thought having an MBC was a good thing? why would it be a good idea to remove? and yes the car has a decent boost gauge.

I'm going to inspect the belts today because although the owner had said that he tuned it up before he gave it to me, the wires had corrosion in them and the plugs were definitely not new (already replaced wires+plugs).

im also going to check if the oil return line is going bad or the gasket.

i don't think it has too many mods besides the cone Air filters, MBC, and the fuel pump. also it has a 2100 clutch (i think thats what its called.. correct me please)

When i change the transmission fluid, do you think i should get it flushed?

im definitely writing a to-do list so keep the suggestions going, i want to get this car in tip top shape.

EDIT: Also do you guys think i should run some seafoam? the STP worked wonders for the sputtering (no more sputtering) maybe it needs a decent internal clean up

EDIT: NVM the sputtering came back. why did it go away for awhile while on the STP?

 

[4g63Powered]

If I were you, I would:

1.) buy an AFPR to keep that fuel pump in check
2.) remove MBC, or turn it down to stock level until you are 100% sure the car is healthy
3.) run a compression test.
4.) replace spark plugs and wires
5.) fix oil leak

As for the leak; do you have any friends that have a fogger (IDK if that's what they're called)? When I had a leak that i could not find, I took it to a garage, reluctantly, and they hooked up a machine that injected smoke/oil fog into the oil system. The smoke then comes out wherever the leak is. Mine was at the cam seal, a place I never would have found myself.

The fuel pressure regulator, when stock, sits on the drivers side of the fuel rail. It is a bronze-ish color.

 

[teknicalissue]

If I were you, I would:

1.) buy an AFPR to keep that fuel pump in check
2.) remove MBC, or turn it down to stock level until you are 100% sure the car is healthy
3.) run a compression test.
4.) replace spark plugs and wires
5.) fix oil leak

As for the leak; do you have any friends that have a fogger (IDK if that's what they're called)? When I had a leak that i could not find, I took it to a garage, reluctantly, and they hooked up a machine that injected smoke/oil fog into the oil system. The smoke then comes out wherever the leak is. Mine was at the cam seal, a place I never would have found myself.

The fuel pressure regulator, when stock, sits on the drivers side of the fuel rail. It is a bronze-ish color.

ah i see what your saying about the MBC, isn't stock psi 11? im not too far off =P

spark plug wires have been replaced by some bosch (i will get NGK's in the future) and plugs have been replaced by NGK's (im reading on here that the gap is supposed to be .28.. autozone said it was .32) so i may have to gap them.

are AFPR easy to install? (for a somewhat n00b like me)

sadly, i don't know anyone with a fogger.. any other ways of detecting said leak?

 

[viprez586]

Honestly, if you don't know what your doing it would be wise to contact a mechanic.
If you don't have the cash for that though, I advise researching a lot before you jump in with two feet.
Biggest thing here : MAINTENANCE BEFORE MODIFICATIONS. Get this car in good shape before you go trying to run 12s with worn components.
Some DSMers are very helpful, you can try going on some local DSM forums, or sub sections on here to look and see if someone will give you a hand, or at least look over your car and tell you what you need.

Don't listen to kids who tell you to vent your blow off valve, or stick a bigger air filter on cause it gives you more HP. Look for the more experienced gurus.

11psi is pretty normal, even for the restrictor being removed in the BCS. A MBC will not turn down the boost past that. 11psi is pretty safe for the stock fuel system. With the walbro 255 your running rich at idle/ throughout the entire rev range which is why your turbo manifold is glowing (not a header).

Search boost leak test on here, you can make your own or buy one and use soapy water to find leaks.

Only thing I can think of as "black plasticy things that make a loud slamming noise" are the driveshaft carrier bearings. These aren't a typical back-yard mechanic job. I'd recommend a buddy or someone with more experience to replace these. Otherwise READ READ READ.
You can do the epoxy fix with them but you need to do it carefully.
I did it to mine temporarily but it wasn't the best fix in the world.

The sputtering is likely:
Plugs - go NGK standard coppers gapped at .028".
If the plug wires are bad/ rough get some new ones.
The walbro 255 causing you to run rich.
Any boost leaks.

Seafoam on a new motor is pointless.

 

[teknicalissue]

alright,

I will post back with all of my results from today.

what i understood from research + this thread

Maintenance Before Modification is key!

things to do ASAP:

1) Check Compression
2) Check Timing Belt
3) Find/Fix for Boost Leak
4) Find/Fix oil leak
5) Change Transmission fluid
6) Get AFPR and install it
7) get Wideband, boost, and volt gauge's
8) Check for why engine may be running too lean
9) Coolant flush
10) Change transfer case fluid
11) Change Rear Diff. Fluid
12) Clean out the intercooler
13) fix the carrier bearings
14) Seafoam
15) MOD!

Would i be missing anything else? I usually go to a shop after work and i can use all of their tools and machines for a good amount of time (including the lifter and such)

EDIT: the motor is not new, its just rebuilt.. does that make a difference?

 

[viprez586]

alright,

I will post back with all of my results from today.

what i understood from research + this thread

Maintenance Before Modification is key!

things to do ASAP:

1) Check Compression
2) Check Timing Belt
3) Find/Fix for Boost Leak
4) Find/Fix oil leak
5) Change Transmission fluid
6) Get AFPR and install it
7) get Wideband, boost, and volt gauge's
8) Check for why engine may be running too lean
9) Coolant flush
10) Change transfer case fluid
11) Change Rear Diff. Fluid
12) Clean out the intercooler
13) fix the carrier bearings
14) Seafoam
15) MOD!

Would i be missing anything else? I usually go to a shop after work and i can use all of their tools and machines for a good amount of time (including the lifter and such)

EDIT: the motor is not new, its just rebuilt.. does that make a difference?

Your running rich due to not having an AFPR.
Seafoam is pointless on a fairly new (15k) motor.
A volt gauge is really pointless - I'd save money for something else.
A wideband isn't necessary unless you plan on turning up the boost. You really can't turn it up that much on stock injectors w/o being fairly experienced and knowledgeable of what you need to do for the car to run properly.
A boost gauge is necessary because the "boost" gauge on the dash is a calculation by the ECM, it's not accurate what-so-ever.

OH!, if your doing maintenance a good thing to do a lot of people forget about is to bleed your hydraulic brake system and flush out the old fluid.
It sounds like your automatic? Otherwise I'd reccomend doing the hydraulic clutch fluid as well. (It's brake fluid too). Be careful you just don't snap a bleeder plug off cause then your F'd!

 

[teknicalissue]

Your running rich due to not having an AFPR.

Ah i see

Seafoam is pointless on a fairly new (15k) motor.

so a rebuilt motor is the same as a new one.. i see

A wideband isn't necessary unless you plan on turning up the boost.

how would i know if im running too lean or too rich when i get the AFPR if i don't get the wideband?

A boost gauge is necessary because the "boost" gauge on the dash is a calculation by the ECM, it's not accurate what-so-ever.

yep, i have a boost gauge ( not the dash )

And no, i dislike (for a lack of a better word) auto. I'm running on manual

 

[viprez586]

OP, best thing to do is post a picture of your engine bay. The more pics the better. That way we can spot if something is out of place/wrong/needs attention.

You can pick up a data logger for a fraction of the cost.
But hell if you plan on doing your own tuning anyway, sure go ahead and get a wideband right away - since you'll probably get one eventually.
Make sure it's a wideband not a narrowband.

AEM UEGO is best bang for buck.

 

[teknicalissue]

I see, so just buy a data logger and log if its too rich or too lean when i get the AFPR


heres a pic

You must be logged in to view this image or video.

let me know if you need a picture from a certain angle i don't have too much room as you can see

EDIT: OH i forgot to mention that my oil dipstick was popping out. so i pinched the top a little

yes, yell at me, i'm a noob that's my excuse

 

[viprez586]

Hmm, I don't see anything jumping out at me.
As for vacuum lines heres the scoop.
You want the BOV to have a single untouched dedicated vacuum pressure source - so the intake manifold.
You also want your pressure source for the wastegate to be un-touched and dedicated.

I made a diagram a while ago for a member who was confused. Don't hate on my MS paint skillz.
<img src="http://www.dsmtuners.com/gallery/files/7/2/2/1/8/simple.bmp" alt="Mbc For Idiots" />

The dipstick popping out isn't the best sign in the world, what you did is okay.
This means you have blow by - but a compression test will tell you how serious this matter is.

*EDIT* I almost forgot while doing maintenance stuff you should change you coolant too. 50/50 mix works well. Buy a spill free funnel - it's super cheap and you don't make a mess. Make sure you burp your coolant system properly so you don't get air pockets in the system.

You must be logged in to view this image or video.

Here are some helpful sites:
www.vfaq.com
http://www.vfaq.com/TMO/Tuning-Tips.htm
http://www.vfaq.com/TMO/
http://mmcdlogger.sourceforge.net/ <--Great open source data logging program. Version 1.8 is latest and it's FREE!
http://www.dsmtuners.com/forums/frequently-answered-dsm-questions/344490-download-1g-service-manuals.html

 

[teknicalissue]

Hmm, I don't see anything jumping out at me.
As for vacuum lines heres the scoop.
You want the BOV to have a single untouched dedicated vacuum pressure source - so the intake manifold.
You also want your pressure source for the wastegate to be un-touched and dedicated.

I made a diagram a while ago for a member who was confused. Don't hate on my MS paint skillz.
<img src="http://www.dsmtuners.com/gallery/files/7/2/2/1/8/simple.bmp" alt="Mbc For Idiots" />

The dipstick popping out isn't the best sign in the world, what you did is okay.
This means you have blow by - but a compression test will tell you how serious this matter is.

interesting diagram

I would love for a DSM guru to seriously give an eyeball to my car

what would happen if the compression test comes out to be bad? what do i do then?

also when the dip stick came out, there was steam or smoke coming out of the tube.......

 

[viprez586]

It's up to you what you wanna do. It all depends on the compression test.
It's either Rebuild it, buy a new engine, drive it, or sell it.

OR your dipstick is so old and dry rotted it's shooting out on its own.
^ Hope that's the case.^

 

[teknicalissue]

It's up to you what you wanna do. It all depends on the compression test.
It's either Rebuild it, buy a new engine, drive it, or sell it.

OR your dipstick is so old and dry rotted it's shooting out on its own.
^ Hope that's the case.^

very true

i will post back the compression test as soon as i get the chance.

if everything goes well ill start checking for everything else

 

[ReYnd]

Since you already mentioned needing to clean out the intercooler, how much oil have you found in your intake tract? If it's a lot (relatively; more than a light coating), in addition to your dipstick popping out, your PCV valve may be bad. You should replace it only with a new Mitsubishi unit, yet one more thing for which you don't want the run-of-the-mill part store product. Luckily it's only $7 or so from all of the vendors on this site.

 

[viprez586]

Since you already mentioned needing to clean out the intercooler, how much oil have you found in your intake tract? If it's a lot (relatively; more than a light coating), in addition to your dipstick popping out, your PCV valve may be bad. You should replace it only with a new Mitsubishi unit, yet one more thing for which you don't want the run-of-the-mill part store product. Luckily it's only $7 or so from all of the vendors on this site.

+1, Buy 2 and keep the extra someplace safe for when you need a new one. Especially if you have a lot of blow by/ low compression.

 

[XiKeiyaZI]

Haha. I love the look of the engine bay, that's how my GSX looked when I found it.

I just want to make it clear to you, since you seem to be interested in actually addressing your vehicles' issues, that driving it with that Fuel pump and no AFPR should be out of the question. That is one of the priorities, is to get an AFPR. They are fairly inexpensive and will help you tremendously.

Keep us updated as you work so we know the condition of things as they are resolved.

 

[teknicalissue]

ok so i didn't get too much time yesterday with the car, but i was able to get compression readings...

1. 100
2. 90
3. 110
4. 110

i don't understand why they are all below the 140 (which i read was the normal compression).. but they seem fine to me except for number 2 which is a little lower than 15% (by 3.5). Maybe the owner put in lower compression pistons?

Also i check my pcv and its running good, not issues there. i havent checked for a boost leak but i think i have one since when i gun it the psi differs from 11 to 12.

yes the next thing i will purchase for my vehicle will be AFPR.

What are your opinions about the compression? any ideas/thoughts?

 

[Clinical]

ok so i didn't get too much time yesterday with the car, but i was able to get compression readings...

1. 100
2. 90
3. 110
4. 110

i don't understand why they are all below the 140 (which i read was the normal compression).. but they seem fine to me except for number 2 which is a little lower than 15% (by 3.5). Maybe the owner put in lower compression pistons?

Also i check my pcv and its running good, not issues there. i havent checked for a boost leak but i think i have one since when i gun it the psi differs from 11 to 12.

yes the next thing i will purchase for my vehicle will be AFPR.

What are your opinions about the compression? any ideas/thoughts?

I'm starting to get skeptical of how 'rebuilt' that motor really is.
It's very possible it could be a 200k+ motor
Stock ones that are at least somewhat maintained can be extremely reliable, and that one may have been stock for most of its life, since it basically is still stock aside from the few things the previous owner did.

Do you have receipts for the rebuild?

 

[FLASH1970]

Yeah, those numbers are low. How did you do the compression test? The next thing to do would be a leakdown test. That will tell you where the air is going.

 

[teknicalissue]

Yeah, those numbers are low. How did you do the compression test? The next thing to do would be a leakdown test. That will tell you where the air is going.

I unplugged the wires from the coil pack, pulled out wire and plug from each cylinder, placed the compression reader. and cranked it while keeping foot on the throttle.

how exactly would i go about in performing the leak down test?

(would that explain why the compression gauge immeadiately dropped down as soon as the car finished cranking? the mechanic who was somewhat helping me toldme that it should be staying up at the highest number)

I'm starting to get skeptical of how 'rebuilt' that motor really is.
It's very possible it could be a 200k+ motor
Stock ones that are at least somewhat maintained can be extremely reliable, and that one may have been stock for most of its life, since it basically is still stock aside from the few things the previous owner did.

Do you have receipts for the rebuild?

sadly no i don't have receipts for the rebuild.



i would totally love a wrench fest by now

(would low compression have anything to do with the car taking long to start up when its cold?)