idle problem and a couple of other problems

[danny7481]

heres the deal, this is my brother-in-laws car, 95 eclipse with the 420a, manual tranny. the timing belt broke and bent some valves, i got the valves fixed, put new headgasket on and new timing belt, car runs fine except for a couple of things, itll start out idling around 800-900 rpms and then itll rev up to around 2k and kinda fluxuate between 1500-2k. another problem is while driving it down the road itll jerk back and forth. kinda reminds me of someone learning how to drive a standard. while its jerking back and forth if you let off the gas itll stop doing it. ive changed the spark plugs and cleaned the throttle body, changed PCV valve, and changed a few vaccum hoses. and check them all for leaks. and ideas would be great, thanks.

 

[dsmdragon]

Well, The vacum to the manifold will cause your idle to go up to around 2000. I took my pcv house to the manifold off and it did the same thing. But it might be another house going to it. If you are just driving down the road and it starts to kick on you like that you could try and check if you are getting fuel when you hit the throttle. Since you are letting off and it fixes it then thats at idle, but if you hit the gas and there isn't any presure there to dilver any then you might wanna start there. I could be a relay or a safty switch (but your car might not start at all if its a safty switch)

So check vacum to manifold then check the fuel presure

 

[4UH8ERS]

heres the deal, this is my brother-in-laws car, 95 eclipse with the 420a, manual tranny. the timing belt broke and bent some valves, i got the valves fixed, put new headgasket on and new timing belt, car runs fine except for a couple of things, itll start out idling around 800-900 rpms and then itll rev up to around 2k and kinda fluxuate between 1500-2k. another problem is while driving it down the road itll jerk back and forth. kinda reminds me of someone learning how to drive a standard. while its jerking back and forth if you let off the gas itll stop doing it. ive changed the spark plugs and cleaned the throttle body, changed PCV valve, and changed a few vaccum hoses. and check them all for leaks. and ideas would be great, thanks.

The high idle would naturally point to a vacuum leak, but not necessarily in the hoses. Check the actual throttle body gasket for leaks.

The jerking? is it when you first push the throttle after coasting? or what?

 

[4UH8ERS]

If you are just driving down the road and it starts to kick on you like that you could try and check if you are getting fuel when you hit the throttle. Since you are letting off and it fixes it then thats at idle, but if you hit the gas and there isn't any presure there to dilver any then you might wanna start there. I could be a relay or a safty switch (but your car might not start at all if its a safty switch)

..........................WTF..........im a little confused with what your saying there.

 

[danny7481]

The high idle would naturally point to a vacuum leak, but not necessarily in the hoses. Check the actual throttle body gasket for leaks.

The jerking? is it when you first push the throttle after coasting? or what?

the jerking doesnt happen when you first push the throttle, it may not start until your doing 60mph or so, and when it does it, if you let your foot off the gas, it will stop, but when you put your foot back on the gas, itll go back to jerking. it does do it all the time, just sometimes and it seems mostly when your going 60+ mph.

i may have got a couple of vaccum hoses backwards, does anyone have a diagram of where there suppose to go? thanks.

 

[freshlane]

here is one from MOD. Hope it helps

http://chicagotuningnetwork.com/random_images/95eclipsevac.JPG

....and

Defiant posted this pretty good link in another thread

http://www.ecanfix.com/users/manualc..._line_info.pdf

 

[danny7481]

in my last post, i said, it does it all the time.. i meant to say it does not do it all the time
like tonight, i drove it a total of 80 miles and it hardly jerked at all, but did a little, but nothing like yesturday. i also forgot to mention that sometimes when you come up to a redlight or such itll idle so low the motor will die.

 

[danny7481]

all my vaccum hoses are correct. i do have a question, when i was putting the motor back together i cleaned the throttle body with a rag and some carb cleaner, i just noticed in the book it says to remove the throttle position sensor before cleaning the TB. could i have messed that up? i didnt spray any carb cleaner directly in it, i sprayed the rag and wiped the inside.

freshlane, your link doesnt work.

 

[Shadow98]

Make sure your TB plate seals completely when you're not stepping on the gas.

 

[danny7481]

Make sure your TB plate seals completely when you're not stepping on the gas.

at idle, it should be completly closed? what about when you press the gas petal all the way to the floor, should it be completly open?

 

[Lurch04]

I have the same problem that he has. Sometimes my eclipse will idle at 1500, then jump to 2k. I've even had it go to 3k. That happens when i had my a/c on and then i turn it off. It also does the jearking thing. but it doesn't happen up around 60 mph. I'll go from first gear to second and as i apply gas, the turbo will start to spool and then it's as if it starts to leak from some where. the power that it was building, is just gone. I still don't know what the problem is, but many people have givin me a couple of ideas of what it might be. some say that it's because i might have the stock oem, which is plastic and rubber, that causes it to flex and that's where it's loosing the power. Someone else also told me that stock oem bov is leaking aswell.

 

[VelocitàPaola]

here is one from MOD. Hope it helps

http://chicagotuningnetwork.com/random_images/95eclipsevac.JPG

....and

Defiant posted this pretty good link in another thread

http://www.ecanfix.com/users/manualc..._line_info.pdf

Please keep pictures to 700x700 pixels or less.

And that diagram is for the 4G63. Here's one for the 420A:

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

 

[danny7481]

mine seems to only jerk around when im cruising a certain speed, like 60 or 70.
but when taking off from a red light, it doesnt do it. im wondering if its the TPS, maybe a throttle cable sticking (although the cruise control seems to work fine). whenever i had the car tore apart, i got new spark plugs, could that be a problem? i gapped them a .050.

 

[danny7481]

whats the black box under the intake manifold for? the 2 vaccum lines coming off of it are in the correct place, but does it matter if they are backwards? surely not, but wanted to check.

 

[Locke]

i got new spark plugs, could that be a problem? i gapped them a .050.

Wouldn't think so, but:

My car used to give me odd problems, like back-firing when starting, the occasional jerk, and a general lack of power. Various tests left me clueless and aggravated. I ended up shortening my plug gap down towards .036. I think my coilpack is taking a crap on me. Car runs awesome now.

I would try looking elsewhere first, though.

 

[danny7481]

the jerking around has seemed to stop (hasnt done it in 2 days). the idling problem is still there though, like today for example, i crank the car up, the idle drops so low it kills the engine, so i crank it back up, hold the gas down for about 5 seconds or so, then it idles around 800, i had to go to several places and each time i left them it would do the same thing, but when i would stop at a redlight, it would idle ok, sometimes it idles at 800 sometimes 1k sometimes 1200. is there anyway to adjust the idle? i cant find any kind of adjustment screw.

 

[TheCykotik1]

no way to adjust the idle, but it sounds like you either have a problem with your idle control valve or your throttle body gasket is leaking. as for the jerking are you 100% sure you set the timing right when you did the belt, because if its off the car will jerk at a certain RPM, but you say it does it at 60 so not too sure about why it would only do it at a certain speed. and if someone could elaborate on what the heck the black box under the intake manifold actually does, that would be great because i have also wondered what the hell that was for a while.

 

[Blitzeclips]

the jerking around has seemed to stop (hasnt done it in 2 days). the idling problem is still there though, like today for example, i crank the car up, the idle drops so low it kills the engine, so i crank it back up, hold the gas down for about 5 seconds or so, then it idles around 800, i had to go to several places and each time i left them it would do the same thing, but when i would stop at a redlight, it would idle ok, sometimes it idles at 800 sometimes 1k sometimes 1200. is there anyway to adjust the idle? i cant find any kind of adjustment screw.

ANS: IAC sensor.

Okay, since everything you tired hasn't worked, let me see if I can throw some ideas out there...

1) .50 is pretty high for a n/a car. I'd lean torward .35 or .40. Somewhere around there. Also check the plugs to see if you're running uber rich, or lean. The gap would also accomedate for what you see..

2) I had the same stalling problem at random. I pulled my MAP sensor and found carbon build-up all over it. I cleaned it, sprayed the housing with some CARB cleaner, and haven't had the problem since.

3) Find a TPS and buy it. Put it in there and check it out. Or go to a local junkyard/friend, etc.. My buddy gave me his TB with the sensor still in it. I pulled it out and use it when I have to diagnose something. It's very helpful to have extras of these things. They're rather cheap, and worth the money when the occassion rises.

Lastly, do you have 95? Your profile doesn't have ANY information so I cannot tell you if the ECU would be troublesome or not. 95's are notorious with failing/wierd ECU's. Stalling, random shut off, etc. is usually a considerable symptom for ECU failure.

Good luck.

 

[danny7481]

yes the car is a 95, and the jerking around has stopped. it only does the low idle thing right now, otherwise the car runs great. the throttle body gasket is new. i am thinking the idle control valve, or whatever its called. i dont think this car has a map sensor. thanks for all the help.

 

[VelocitàPaola]

All 2G N/Ts have a MAP sensor. My suggestion is to check/replace the TPS. Your problems sound similar to something I was experiencing once. It turned out to be my TPS, and I've been idling at a steady 750-900 RPMs since.

 

[4UH8ERS]

To answer your question about the little black box: its the cruise control vacuum box.

 

[TheCykotik1]

thanks

 

[DSMcrazy3]

I would put money on the ECU being the culprit. I experienced the exact same problems, especially the dying right after I started her up. I would have to hold the idle a tad bit higher than usual with the gas pedal to help get the car going, and baby it down to normal idle so it wouldn't die. Sometimes when I would pull up to a stop sign or red light the car would die also until it died at one and never fired back up. ECU was the problem. It's hard to say that is the problem, but I'm leaning more that way having experienced it and seen many of the symptoms you're describing right now.

 

[DJ_Obscene]

You might want to check the idle air control valve. I had a similar problem a while back. On my way to the shop the car was just jerking all the way there.

 

[vbeclipseracer]

that carb cleaner prob messed up the throttle position sensor. go to advance auto and get a new one and see if it clears up if not take it back and put the old one back on