Two Guys Garage Forum  

Go Back   Two Guys Garage Forum > Your Own Projects

Thread Tools Search this Thread Display Modes
Old 06-07-2002, 03:08 AM
puma puma is offline
Registered User
Join Date: Jun 2002
Location: California
Posts: 1
puma is on a distinguished road
turbo problems of a mitsubishi 3000 GT

I recently bought a 1991 Mitsubishi 3000GT VR-4 Twin turbo.
I am experiencing a problem with the turbos.
When I depress the gas pedal all the way down the turbo starts build up pressure and the when I reach about 4000 rpm Ihear a buzzzz sound coming form the engine compartment and it feels like I am not getting the anymore boost from the turbos.
Does anyboy in this have an answer?

One more question
Is it true that if I replace the stock muffler on my car with one of those universal one, Will it damage or intefere with performance of the turbos if the inle of the new muffler is bigger or smaller?

I would appreciate if anybody could give some advise on these problems before I take it to the shop.
Reply With Quote
Old 06-09-2002, 10:33 PM
Fordrockschevy Fordrockschevy is offline
Registered User
Join Date: Apr 2002
Location: ny
Posts: 107
Fordrockschevy is on a distinguished road
Send a message via AIM to Fordrockschevy
Ok here is how you fix it!!!!

Get 5000 dollars and a stick of dynomite, blow up the 3000 gt and go out and bye a fairly older ford mustang like a pony car from the 80s drop a 5.0 into and hook up some nos and it would toaste that 3000 gt.
" They say the difference between men and boys is the price of there toys"
Reply With Quote
Old 06-10-2002, 01:38 AM
thecarguy's Avatar
thecarguy thecarguy is offline
Trademark Motorsports
Join Date: Nov 2001
Location: So Cal
Posts: 3,048
thecarguy is on a distinguished road
Send a message via AIM to thecarguy

turbos nedd constant attention. ive heard that after 1-2,000 miles they go bad and dont put out power and will eventually give out. as for the muffler: there is a certin amount of flow within the exaust system. It makes sense to me that a more free flowing exaust would create less pressure within the system. Kind of like when you put your thumb over a hose, its free flowing till you put your thumb on it but with the thumb you have pressure.
Reply With Quote
Old 06-11-2002, 10:58 AM
Posts: n/a
How much boost are you hitting at 4000 rpm? My guess would be that you're hitting a certain pressure and then air is escaping somewhere. Check all the hose's and clamps that are associated with the turbos. ALso make sure all your vacuum lines are in good shape. Turbo cars really don't like vacuum leaks
Follow the hoses from the intake back and see where there is a leak.

Putting a less restrictive exhaust on your car might cause to you get boost spikes, since the exhaust will be able to exit easier and more quickly. But i'd check with some 3000gt websites and see what they have to say before you shell out the $$

Reply With Quote
Old 06-11-2002, 03:59 PM
Posts: n/a
look here for more answers
be sure to look at faq's and message board. i had a 3000gt and was able to fix an idle problem myself by using the info i found there..... saved me hundreds of bucks.
could be faulty bleeder valve dumping your turbo pressure.

Last edited by dancerman; 06-11-2002 at 04:01 PM.
Reply With Quote
Old 06-13-2002, 06:53 PM
rapideo rapideo is offline
Registered User
Join Date: May 2002
Location: austin
Posts: 399
rapideo is on a distinguished road
could it be a waste gate is opening to regulate the maximun pressure the engine can handle
Reply With Quote
Old 06-20-2002, 05:40 PM
JackDonkey JackDonkey is offline
Registered User
Join Date: Jun 2002
Posts: 2
JackDonkey is on a distinguished road
change your sparkplugs
Reply With Quote
Old 06-21-2002, 05:21 PM
Rally Art Rally Art is offline
Registered User
Join Date: Jun 2002
Posts: 13
Rally Art is on a distinguished road
Send a message via AIM to Rally Art
turbo's do not last long at all, best thing you should do if you drive your car a lot is get something else that will last longer that suits your driving needs like a supercharger or something
Reply With Quote
Old 06-26-2002, 12:20 PM
JackDonkey JackDonkey is offline
Registered User
Join Date: Jun 2002
Posts: 2
JackDonkey is on a distinguished road
Kenworths and Peterbuilts have Turbos, and they put on quite a few miles under heavy load. I think turbos are quite reliable.

The problem may be completely unrelated to the turbo.

I had a similar problem with my 95 Eclipse GSX, if I got on the gas too much there would be like a vibrating noise (accompanied only by a slight vibration in the engine compartment) and the car seemed to lose a little power, but would continue to accelerate. So I could only get on the gas up to a point. At 70000 miles I spent $10 and 1 hour on some Bosch Platinum spark plugs, gapped them up just right, I think it was .025" and the problem was solved. I also hung out with some mitsubishi guys for a while and the 3000GT guy always had a spare set of spark plugs for himself and anyone else that wanted them. So I think that the 3000GT may have a similar problem to the Eclipse, and judging by the fact that the 3000GT guy always seemed to have a spare set of plugs, the spark plugs may be the issue.
Reply With Quote
Old 06-26-2002, 11:49 PM
Posts: n/a
Well, I'm a diesel mechanic and I work on turbo's on a regular basis. I don't have any experience with your particular vehicle, but i have an idea. The bearings in the turbo are what wear out. After a lot of miles (I've seen some diesels go over 20,000 hours-not miles-hours on the original turbo. If you do the math, that's over 833 twenty four hour days and we all know that no one drives their vehicle like that!) the shaft bearings get sloppy and at high turbo speeds the shaft actually will vibrate around and lose speed causing a loss in boost. If it gets bad enough, the fan or compressor wheel can actually make contact with the housing and really cause mayhem. I've actually seen parts of compressor wheels make it into the engine cylinders = new engine. A catastophic failure of the bearings dumps all kinds of metal into the oil, also a very bad thing. Typically, when the bearings get sloppy, the oil seals on the turbo shaft start to leak. Check to see if you have any oil either coming out the exhaust or out the pressure side of the turbo. If there's any oil present, the seals are shot and so are the bearings - Time for a new turbo. Preferably as soon as possible before it has a chance to fail! As far as the muffler goes, the best muffler is no muffler. The faster the exhaust gasses can escape the engine, the faster the turbo will run, the more boost it makes. This actually helps the turbo to run cooler too and extends it's service life, not to mention make a few more horses. The engine will scavenge better too if the turbo is running faster, and should help it to burn cleaner and can increase fuel mileage. Good luck and I hope this helped!
Reply With Quote

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Diesel Turbo Housing Muddywoman Your Own Projects 8 03-30-2006 03:02 AM
95 mitsubishi eclipse 2.0 non turbo used to know Your Own Projects 5 03-13-2006 10:35 PM
Et Turbo Brutus? Ferdinand? Donaldo88 Wheels and Deals 3 06-06-2005 07:47 PM
Turbo Charger sskula Your Own Projects 4 06-15-2004 12:03 AM
Turbo Question for WRX's scottking Your Own Projects 0 06-14-2002 12:51 PM

All times are GMT -4. The time now is 08:04 PM.

Powered by vBulletin® Version 3.8.2
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd. © Brenton Productions