Welcome to DSMtuners - the largest Mitsubishi Eclipse, Eagle Talon, 4G63t and 420A DSM performance resource on the web



















Login



Go Back   DSMtuners > DSM Forums > General > Newbie Forum
Welcome to DSMtuners - the largest Mitsubishi Eclipse, Eagle Talon, 4G63t and 420A DSM performance resource
You are browsing the site as a GUEST. Please login (or register) and gain the ability to post on our site and interact with other DSMers. You also get to browse the site with fewer advertisements. It is FREE to join!

Newbie Forum: Beginner/newbie/general DSM modification questions. First mods, how to run 10's when you haven't run 12's yet, any tech question that doesn't fit in another tech forum. Probationary Members must limit their tech posts to this forum and sub-forums.

Reply
 
 
LinkBack   Thread Tools
Old 04-01-2009, 12:15 PM Show Printable Version Show Printable Version   Email this Post to a Friend Email this Post      #1 (permalink)
Probationary Member
 

streetlegalcars's Avatar
Registered: Apr 2009
Tech Posts: 7
Reputation: streetlegalcars is an unknown

Backfire at idle


this has been bugging me for a while. I have 1 maybe 2 problems I have a backfire at idle only when the car reaches operating temperatures. I have a code 24 and a code 25 iac has been replaced the car idles 2 or 300 rpms higher than it should. also sometimes when i rev up the idle doesn't snap back down it idles high for a while then slowly goes back down. plugs and wires are fine. but the car burns rich. and the vacuum pressure is low. my vacuum tester says it has late ign timing. I cant find any leaks. any help is appreciated






24 Throttle Position Sensor Voltage Disagrees With Manifold Absolute Pressure.
24 Throttle Position Sensor Voltage High.
24 Throttle Position Sensor Voltage Low.
25 Idle Air Control Motor Circuits.
25 Target Idle Not Reached (plus or minus 200 RPM).



____________________________
95 eclipse gs N/T

mark post as helpful recommend reputation points    Reply With Quote
Old 04-01-2009, 12:24 PM Show Printable Version Show Printable Version   Email this Post to a Friend Email this Post      #2 (permalink)
Proven Member
 

DSM_PWR's Avatar
Registered: Oct 2007
Tech Posts: 1,668
Photos: 53
Classifieds Rating: 45
Reputation: DSM_PWR is pretty helpful and trustworthy
Have you tried swapping out your TPS?

Try unplugging the TPS during idle and see if it makes any difference, if nothing its possibly bad...

Or the seals in the throttle body are bad as well, most commonly seen on N/A from my experience.. dunno why... but it will casue the low idle and bad readings like the ones your getting..


____________________________
DSM_BOY
View photos of this member's car 

mark post as helpful recommend reputation points    Reply With Quote
Old 04-01-2009, 12:34 PM Show Printable Version Show Printable Version   Email this Post to a Friend Email this Post      #3 (permalink)
Probationary Member
 

lilchrishall's Avatar
Registered: Oct 2008
Tech Posts: 3
Photos: 4
Reputation: lilchrishall is an unknown
It sound like your manafold has a crack in it.
View photos of this member's car 

mark post as helpful recommend reputation points    Reply With Quote
Old 04-02-2009, 08:39 AM Show Printable Version Show Printable Version   Email this Post to a Friend Email this Post      #4 (permalink)
Probationary Member
 

streetlegalcars's Avatar
Registered: Apr 2009
Tech Posts: 7
Reputation: streetlegalcars is an unknown
Im going to swap it out today i have a feeling it may be more than that


____________________________
95 eclipse gs N/T

mark post as helpful recommend reputation points    Reply With Quote
Old 04-02-2009, 11:21 AM Show Printable Version Show Printable Version   Email this Post to a Friend Email this Post      #5 (permalink)
Probationary Member
 

streetlegalcars's Avatar
Registered: Apr 2009
Tech Posts: 7
Reputation: streetlegalcars is an unknown
nope not the tps


____________________________
95 eclipse gs N/T

mark post as helpful recommend reputation points    Reply With Quote
Old 04-02-2009, 11:32 AM Show Printable Version Show Printable Version   Email this Post to a Friend Email this Post      #6 (permalink)
Proven Member
 

brassc2007's Avatar
Registered: Jan 2008
Tech Posts: 374
Photos: 26
Classifieds Rating: 0
Reputation: brassc2007 is pretty helpful and trustworthy

hey


a backfire is usually to much unburnt fuel have you check the idle air control valve (iac), made sure you have good spark on a four cylinder and the plugs aint fouled out, what about the injectors you dont have an injector sticking open dumping fuel do you, what about the o2 sensors, it could be a number of things, any codes, does this happen only after the car is warmed up or only if the car is cold sensors read differently at different temps the sensor may work fine when cold but not at all when warmed up and vise versa kind of need more info here to really help ya lol
View photos of this member's car 

mark post as helpful recommend reputation points    Reply With Quote
Old 04-02-2009, 11:34 AM Show Printable Version Show Printable Version   Email this Post to a Friend Email this Post      #7 (permalink)
Proven Member
 

brassc2007's Avatar
Registered: Jan 2008
Tech Posts: 374
Photos: 26
Classifieds Rating: 0
Reputation: brassc2007 is pretty helpful and trustworthy
another question does it surge at all at idle?
View photos of this member's car 

mark post as helpful recommend reputation points    Reply With Quote
Old 04-03-2009, 12:37 PM Show Printable Version Show Printable Version   Email this Post to a Friend Email this Post      #8 (permalink)
Probationary Member
 

streetlegalcars's Avatar
Registered: Apr 2009
Tech Posts: 7
Reputation: streetlegalcars is an unknown
Iac was replaced. new plugs, wires are fine. one o2 was replaced the codes are listed above.
Im not able to check injectors.

im going to remove the vacuum lines and block the egr and see what that does


____________________________
95 eclipse gs N/T

mark post as helpful recommend reputation points    Reply With Quote
Old 04-04-2009, 12:47 AM Show Printable Version Show Printable Version   Email this Post to a Friend Email this Post      #9 (permalink)
Proven Member
 

brassc2007's Avatar
Registered: Jan 2008
Tech Posts: 374
Photos: 26
Classifieds Rating: 0
Reputation: brassc2007 is pretty helpful and trustworthy
I did a little seaching on here and and i found a few other posts that recommend checking the egr valve and vacuum lines but usually a vacuum line causes a rough idle or a miss. A easy way to check the injectors is to unplug them i mostly use it to see if they are firing but maybe you can do it do see if when you unplug the injector if the backfire goes away it sounds like it is maybe running a little rich to me at idle which may explain why it only does it at idle cause it would be using the fuel under a load. Let us know if you find out anything new.
View photos of this member's car 

mark post as helpful recommend reputation points    Reply With Quote
Old 04-04-2009, 11:55 AM Show Printable Version Show Printable Version   Email this Post to a Friend Email this Post      #10 (permalink)
Probationary Member
 

streetlegalcars's Avatar
Registered: Apr 2009
Tech Posts: 7
Reputation: streetlegalcars is an unknown
The backfire started before the high idle that's why I think there two different problems.


____________________________
95 eclipse gs N/T

mark post as helpful recommend reputation points    Reply With Quote
Old 04-04-2009, 04:55 PM Show Printable Version Show Printable Version   Email this Post to a Friend Email this Post      #11 (permalink)
Probationary Member
 

streetlegalcars's Avatar
Registered: Apr 2009
Tech Posts: 7
Reputation: streetlegalcars is an unknown
egr is gone vacuum lines are gone in going to try to check the injectors if that dont work im pulling the intake off


____________________________
95 eclipse gs N/T

mark post as helpful recommend reputation points    Reply With Quote
Old 04-04-2009, 05:30 PM Show Printable Version Show Printable Version   Email this Post to a Friend Email this Post      #12 (permalink)
Proven Member
 

brassc2007's Avatar
Registered: Jan 2008
Tech Posts: 374
Photos: 26
Classifieds Rating: 0
Reputation: brassc2007 is pretty helpful and trustworthy
any luck with trying the fuel injectors if it is a vacuum leak you can spray some wd-40 around the intake gasket and around the intake and if the idle speed goes up then comes back down when you spray a certian area that is your vacuum leak but dont spray when the motor is hot for safety purposes. to me it seems kinda quick to pull the intake did you check for exhaust leaks
View photos of this member's car 

mark post as helpful recommend reputation points    Reply With Quote
Old 04-04-2009, 05:31 PM Show Printable Version Show Printable Version   Email this Post to a Friend Email this Post      #13 (permalink)
Proven Member
 

brassc2007's Avatar
Registered: Jan 2008
Tech Posts: 374
Photos: 26
Classifieds Rating: 0
Reputation: brassc2007 is pretty helpful and trustworthy
a vacuum leak can cause both high idle and backfire depending on the air to fuel ratio
View photos of this member's car 

mark post as helpful recommend reputation points    Reply With Quote
Old 04-05-2009, 09:37 AM Show Printable Version Show Printable Version   Email this Post to a Friend Email this Post      #14 (permalink)
Probationary Member
 

streetlegalcars's Avatar
Registered: Apr 2009
Tech Posts: 7
Reputation: streetlegalcars is an unknown
i havent tried yet my radiator popped a hole in itself


____________________________
95 eclipse gs N/T

mark post as helpful recommend reputation points    Reply With Quote
Reply

Bookmarks

Thread Tools

 

» Recent DSM Photo
» Current Poll
How many times have you been to the Shootout?
1 - 40.00%
168 Votes
2-5 - 41.67%
175 Votes
6-10 - 10.48%
44 Votes
11-15 - 3.10%
13 Votes
16-20 - 4.76%
20 Votes
Total Votes: 420
You may not vote on this poll.
» Online Users: 784
236 members and 548 guests
Most users ever online was 1,704, 03-17-2008 at 09:11 PM.
DSMtuners Main Sections
DSM Forums
DSM Regional Forums
DSM Builds/Journals
DSM Articles
DSM Tech Guides
DSM Upgrade Paths
DSM Parts Reviews
DSM Vendor Reviews

DSM Classifieds
DSM Parts Guides
DSM Photos
DSM Videos
DSM Timeslips
DSM Dyno Sheets
Shirts & Apparel
DSMtuners Decals

Advertising Info
Our Sponsors
Site Rules
Terms of Service
Privacy Policy
Site FAQ
About Us
Contact Us

© 2014 DSMtuners.com - All Rights Reserved

DSMtuners is not affiliated with Diamond Star Motors. The Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, Mitsubishi Galant VR-4, and associated logos are trademarks of Diamond Star Motors, Mitsubishi Motors, and Chrysler Corporation. No, we do not hand out car sponsorships.

All times are GMT -7. The time now is 11:04 AM.


Vendor Tools vBulletin Plugins by Drive Thru Online, Inc.

Search Engine Optimization by vBSEO 3.6.0