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420a idles rough and dies? bad gas mileage

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2ndgen420

10+ Year Contributor
42
0
Aug 6, 2012
knightstown, Indiana
ok i got a 98 eagle talon 420a 5speed non turbo and here lately i've noticed when idling either just after starting or like at a stop light my car will bogg down and hop around between 200rpm and 600rpms until it dies but it will start back up just fine but every time i stop somewhere and the car idles for more than a min. it dose this and also i have been getting horrid gas mileage since this has been going on i've changed my plugs, wires, air filter, catilitic converter and got the rest of the exhaust sealed up and the problem is still their can someone please help me im at a loss of what it could be!!??!!
 
Get your CEL checked out and go from there! Lights there, usually telling you what's wrong! If that don't solve it then move on to the TPS or IAC
 
just get your cel codes checked at autozone and go from there. if your getting bad mileage you might need to do a compression test. you need a vaccum gauge to check for leaks but you need to know what everything is suppose to be at and im not sure off hand what it is suppose to be. do a google check on it.
 
hey guys, havent had a chance to go to autozone to check codes but did get to go to the junkyard and picked up a new throttle body (with the iac and tps) cleaned the heck outta it and its ready to go in so as soon as my old lady gets home and the car cools im going to swap throttle bodies out and see what happens wish me luck ill also let you guys no if it works or not!!
 
make sure your throttle body gasket is good and reusable. and its kinda to late but you could of just cleaned out your iac on the car now. it would of been just as good as doing the same thing to the junk yard one. but hopefully it helps
 
Yeah i thought about that, but it's my daily and was easier to get the junkyard one, witch i got for free, and clean it but i hope it fixes this problem. It's killing my gas mileage, and almost dies at every stop light!

Can i use rtv sealant if my gasket is bad?
 
Good Luck! And you can find vaccum leaks alot of ways. Let your car cool off, then start it and you can spray carb cleaner or starting fluid at all your vaccum lines that go into your intake manifold. OR some people unplug them one by one and cover the opening of the vaccum line with your thumb and I think if it doesnt change your idle the line is leaking. OR you can blow cigar smoke by your vaccum lines while its running and see if any get sucks in. OR with the car off you can unhook a bigger vaccum line like the brake booster and plug in your own little contraption like a rubber tube that'll fit that port and puff cigar smoke into your intake manifold and see if it comes out any of the lines. Also yeah if those sensors go bad or you have a vaccum leak even, your car will idle like crap and your gas mileage will be like half what it normally is. It causes your car not to go into a full loop idle ect. ect. Good Luck
 
Good Luck! And you can find vaccum leaks alot of ways. Let your car cool off, then start it and you can spray carb cleaner or starting fluid at all your vaccum lines that go into your intake manifold. OR some people unplug them one by one and cover the opening of the vaccum line with your thumb and I think if it doesnt change your idle the line is leaking. OR you can blow cigar smoke by your vaccum lines while its running and see if any get sucks in. OR with the car off you can unhook a bigger vaccum line like the brake booster and plug in your own little contraption like a rubber tube that'll fit that port and puff cigar smoke into your intake manifold and see if it comes out any of the lines. Also yeah if those sensors go bad or you have a vaccum leak even, your car will idle like crap and your gas mileage will be like half what it normally is. It causes your car not to go into a full loop idle ect. ect. Good Luck

Thanks, I really hope this l;ike new, clean TB & IAC fix this and if not, i'll do the carb cleaner vaccume check! but from my discription dose it sound like an IAC or TPS?
 
our motors are nortorious with idle issues and its hard to say. everyones case is different you just need to keep checking stuff out and do research. theres alot of threads to read through which might help if the iac and tps dont work out.
 
Ok, I'm going to change everything in about an hour, and if it still presist's I'll do the carb, vac leak check. As soon as i do all that i will post to let you guy's know what's up. But seriously thank you guys you have been nothing but a huge help with this situation! Also can i use blue RTV as a gasket if old TB gasket is bad? Finally, when the idle thing happens right before it dies or correct's it's self it poofs a small gray/white cloud of smoke but that's all the car has ever smoked! Please give feedback!
 
Ok, first off this is my thread, secondly, if you read everything it says i didn't have time to go to autozone to get it checked. Also i know for a fact my IAC is at least dirty so regaurdless i got this TB,IAC,TPS for free and it could be the cause why not change it?
 
Because the time you spend changing this throttle body could have been spent turning your key on to off 3 times and flashing the freaking codes out of it.
 
Because the time you spend changing this throttle body could have been spent turning your key on to off 3 times and flashing the freaking codes out of it.

I have a 98 the key trick only works on 95 and under!


http://troublecodes.net/mitsu/

theres the link to what boosted is talking about. scroll half way down and read the paragraph. also i totally forgot to meantion to check your EGR LOL i took mine off so i spaced it but check that out. unplug your egr sensor and see what happens to your idle it could be stuck open or clogged.

Yeah i thought it could of been the EGR, and tried to get one today but all of them at the yard, looked pretty bad. So tom im going to get a referb, one.
 
Last edited by a moderator:
95-98 Eclipse (Non-Turbo) Retrieval Without Scan Tool


Cycle the ignition key On-Off-On-Off-On within 5 seconds.


images used with permission Copyright © 2001 ALLDATA LLC.



Count the number of times the malfunction indicator lamp (check engine lamp) on the instrument panel flashes on and off. The number of flashes represents the trouble code. There is a slight pause between the flashes representing the first and second digits of the code. Longer pauses (approx. 4 seconds) separate individual trouble codes.
Repair the malfunction while referring to the inspection chart for diagnostic trouble codes.
After disconnecting the battery cable from the battery (-) terminal for 10 seconds or more, reconnect the cable.
Start the engine and run it at idle for about 15 minutes after the engine has warmed up.

Read the link he posted...DSMer
 
I am not sure why this would not work on a '99 as well, I have never seen one personally but I am fairly sure that it works on any Chrysler PCM before 2001 at least.
 
Like i said im new at DSM, and just saying, in the haynes manual it tells you it only works in the 95 & under. I admit I havent tested it but my haynes manual hasn't lied to me yet and Mr. grothe3297venge if you have a problem with me or my threads you can send me a PM, otherwise I'd appriciate it if you did not comment on anything of mine thank you.

And btw everyone, I've never reffered to myself as a DSMer, like I've said numerous times I'm new to them.
 
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