Car trouble

[Dpyle]

So the wife's car is having some issues. The thing is revving to like 3k on it's own shortly after start up. Then the other night it started and was idling down way low after I started it. Took off driving and made it about half a mile before the throttle just cut out completely for a couple minutes then all was fine.

Replace the throttle position sensor today as that seemed a logical move based on symptoms, but that didn't take care of it.

Anyone have any more ideas? I'm thinking the MAF sensor or the idle air control valve. Just looking for some more opinions. Gotta be some more car guys on here.

[DSM4Life]

I always try the easy stuff first. Reset the ECO by removing the negative cable on the battery for a few min and see what happens. You don't use additives tot eh fuel do you?

[gixxerboy1]

could be alot of things. You best bet would to have it scanned and see what code its showing before just buying random parts

[Dpyle]

No no additives to fuel. And Gixx that's what makes this so troubling. It's not throwing any codes through the ECU.

[gearbox]

My first thought was sensor. How many times have to checked to see if its throwing codes

[JP-MAN]

gotta be the flex compasator...

only thing that makes sense...

[gixxerboy1]

what kind of car is it?

[Dpyle]

It's an 07 Kia sportage. Haven't hooked it yet. No check engine light on. Will it still throw codes if the light isn't on?

[RaginCajun]

throttle body could be gummed up. when was the last time you filled up, could be bad gas or like you said earlier, MAF or IAV

[gixxerboy1]

It's an 07 Kia sportage. Haven't hooked it yet. No check engine light on. Will it still throw codes if the light isn't on?

it could still have a code. Also if its a good scanner they can monitor all the sensors and see what going on

[FONZY007]

Doesn't it have a 10 year warranty?

[Dpyle]

Doesn't it have a 10 year warranty?

Bought it used. Before I met her

[FONZY007]

Oh.. Thought the factory warranty still carries over?

Vacuum leak

Throttle cable could be sticking, that happened to me on my Honda, I just lubed the throttle cable and issue went away.. Same issues you described low and high idle

[Dpyle]

Yeah but nothing really explains the throttle going completely out the other night while the car was still running. I mean even with pedal to the floor there was no response. That's why I thought it had to be the TPS.

[Dpyle]

Thanks for the replies everyone. Just wanted to make sure I was headed in the right direction. Guess I'll have it hooked up to check the codes. I'm not much on newer cars outside of performance. More of a classic and custom bike kind of guy.

[DCI]

I'm thinking MAF, or it could be the Idle control Valve also. But as the lads said the best bet is to get scanned properly.

[gearbox]

Yes scan it before doing anything else

[auswest]

Check for codes, shooting in the dark with efi can get expensive. Clean out the t-body it may be the idle stepper motor, easy way to test. Have car at idle with no accessories on, then flick your a/c and lights on causing the engine to load up, you should see the revs drop for a split second, the the revs pick back up again to their original level or there abouts. If the revs drop and stay down the idle stepper motor is fkd and is located externally at the butterfly near the tps also.

[lovbyts]

I'm thinking MAF, or it could be the Idle control Valve also. But as the lads said the best bet is to get scanned properly.

^^^ my 2 guess above. You can unplug the MAF and see if the idle changes. If nothing changes that pretty much tells you the MAF is dead. Sometimes the Idle control valve can be cleaned and works for a while but better to just replace it.

[DCI]

^^^ my 2 guess above. You can unplug the MAF and see if the idle changes. If nothing changes that pretty much tells you the MAF is dead. Sometimes the Idle control valve can be cleaned and works for a while but better to just replace it.

True as lovbyts said you can dis connect them and if stays the same you know it's the maf it will probably through up an injection light with it being disconnected. I know on my own car it wasn't throwing up codes but the car wasn't revving right so I disconnnected the MAF and it was way better without it on as the maf was reading the wrong values which can happen.

[Dpyle]

I'll have to check into it some more. Ran it for over an hour today with no issues. Even with the cold start. Kind of wondering if the new TPS needed time to recalibrate.

[lovbyts]

Whenever you put something like that in it's best to reset values to zero by disconnecting the batter for 10 minutes.

Get a can of starter fluid and spray it around where the hoses are to see if there are any vacuum leaks. If it revs up you know you have a leak in that area. Be careful to not spray to much at one time to let it puddle or on the exhaust manifold so it does not ignite.

[Dpyle]

Yeah I reset when I replaced the tps. Gonna have to check vacuum lines tomorrow. It ran great this morning then got in it this evening and I'm back at square one.

[Scabtree]

I had a similar issue with my 4Runner and after months of fiddling, I replaced the O2 sensor (pre-converter) and all is well. If you do have a scanner, it may indicated a code that is 'pending' (ie no check engine light yet). this would likely tell you the issue.

I would first try to clean the MAF and the throttle body - and be sure to use MAF cleaner.

[lovbyts]

How old is it? The other thing is a lot of cars the capacitors start to leak after about 7+ years and need replaced in the ECU. If you are handy with a soldering iron it's not a big deal. do some Google search and see if anyone has had a problem with it.
Looks like a good Kia Forum
http://www.kia-forums.com/2g-2005-20...-sportage.html

Check this also
http://www.ehow.com/facts_8054400_ki...-symptoms.html

I had a similar issue with my 4Runner and after months of fiddling, I replaced the O2 sensor (pre-converter) and all is well. If you do have a scanner, it may indicated a code that is 'pending' (ie no check engine light yet). this would likely tell you the issue.

I would first try to clean the MAF and the throttle body - and be sure to use MAF cleaner.

You want to be really careful about this, it's not advisable to spray any type of cleaner in the MAF because you can damage delicate air sensing diodes and such. IF you decide to do this and only if it's dirty first do some research to see what to use, dont just use engine cleaner, starter fluids or anything like that. I think only a good electrical cleaner should be used but check into it first or you could kill a perfectly good $300 MAF.

[redz]

Is it a wire throttle or electrically controlled one?

[big88sub]

The check engine light will only come on when the pcm goes threw enough cycles to notice there is a problem. I used to be a mechanic and I'd almost bet money on it being iac. Idle air control valve. If this valve isn't working properly the vehicle cone run fine certain days when the conditions are similar to those when the iac failed. This valve does most of its work on wart up in which it kicks the idle up about 250 rpms until vehicle is warm then drops ide back down to normal to save fuel. It also depends on the temp sensor to let the pcm know when the engine is warm if this sensor fails it could also have very similar effect but both sensors are typically not very expensive. I would start with the idle air control valve. Let me know of that helps.

[big88sub]

There are specific cleaner for maf sensors don't be scared to clean ot. Done it a thousand times. Take it out of the vehicle to clean it. Do not scrub the sensor itself just use the cleaner. They typically have a honeycomb patern around sensor inside.the housing of the maf sensor don't bend or brake any of this.

[redz]

^IAC is a good idea to check, had that problem on a supped up Z24 i used to have(i loved that car when I was 17)

[moseley2004]

Stop trying to fix it yourself. Spend the bucks and take it to someone that knows what their doing. By the time you fix it it would probably take you weeks of labour and hundreds of $ in parts you've bought because that's what you think it is. I see this all the time at my shop! Take it to a mechanic it's cheaper in the end

[lovbyts]

90% of the time the dealer only guesses also. I have seen far to many people who had similar problems take it to the dealer and $1000 later it wasn't fixed. 1st the dealer will say it's the O2 sensor then thy go on the the IAC, MAF, TPS just like we are suggesting but they charge 2x the amount for the parts alone.

Only thing I use the dealer for anymore is if it's under warranty, oil change or a shop to change clutch because I dont want to do the labor. Some of the worst work I have seen is from the dealers. Just my .02.

There is a certain amount of satisfaction to say you did it yourself also.

[moseley2004]

I agree about the dealers. Overpriced rubbish work with monkeys working in the car in a dealership all you are is a number nothing else. Go to an independent. Get some opinions from people on who they trust.

[FONZY007]

Any updates is it fixed?

[Dpyle]

No. Not fixed yet. Gonna get a code reader tonight and see if I can find anything there. Gonna check the vacuum lines too before putting anymore parts on it. It's just weird the throttle keeps going out and no check engine light.

[Dpyle]

I agree about the dealers. Overpriced rubbish work with monkeys working in the car in a dealership all you are is a number nothing else. Go to an independent. Get some opinions from people on who they trust.

Would take it to a shop but with no engine light they'll be guessing same as me. Can't afford the labor on that. Been outta work for 2 weeks and gonna be another couple before the new job starts.

[lovbyts]

Did you try the MAF trick with unplugging it when you are experiencing the problem?

Looks like you had better join one of the forums and find out how to test the suspect parts. Most of them you can test with an Ohm meeter. It can be a PITA but it's cheaper than replacing parts one at a time.

If it's fuel injected it also could be a partially plugged injector. Speaking of have you ever changed out the fuel filter and EGR vulvae?

[big88sub]

Ok I'm not just guessing here well I kinda am but it is an educated guess. I was a mechanic but something that paid more money came along so dad I switched jobs. Been fixing my own stuff since I got my licence and been fixing vehicles longer. I've rebuilt motors transmissions and spent ungodly amount of hrs diagnosing and fixing other people's cars that don't want to have somebody just guessing. If you don't want to take it to a shop listen to me and don't waste anymore time and go and get a iac valve and replace it. Just be careful with it so in the off chance that I am wrong you can take it back off and return it. Like I had said in my previous post the computer doesn't recognize the problem yet and when it does it will probably have a lean fuel air code. Of o had my code book I'd tell you what codes would pop up. O and not to mention I'm a gm master tech if that means anything to you. I'd.like to bet money but I'm thinkin nobody will take me up on it and wouldn't pay up anyways. Just pm me if you have anymore questions.

[lovbyts]

IAC are not cheap but they are easy to test like I mentioned above if you know what the values should be. A lot of time you can fix them or at least emporarily by cleaning the IAC, they get dirty. I like to use a spray called B12, works better than most anything I have used.

[big88sub]

The iac is around iffy bucks just looked it up and yes you can try to clean it and a 2 dollar bottle of bake cleaner is fine as you don't have to worry about any access brake clean going through them and all the brake cleaner is going to evaporate before you get the iac back on the vehicle anyways. I'd just change it as cleaning if it actually works will only buy a little time. If you would like to test this valve next time you start the vehicle (when it hasn't been run all night first thing in the morning will probably be best as the temp outside will be cooler) is pop the hood locate the iac start the vehicle go unplug the iac and if the rpms don't drop or possibly even kill the engine( not kill it bit cause it to stall) the iac is bad its the easy. I'll be watching

[Dpyle]

Didn't get a chance to work on it the last couple of day because of rain. I'll def check the IAC. Thanks again for the help.