Forenza Engine Revs up on it own even in Neutral????

bsharon · Post by **bsharon** » Wed Aug 03, 2005 7:02 pm

Hello everyone.
1st I'm going to be taking my Forenza into the Suzuki Dealer to have a few things checked. But has enyone expeiranced there car just start reving up on its own?? It has happend a few times, and I know something doesn't feel right. It's allmost like speed control, I can put it in 2nd or 3rd gear and it just drives it self faster and faster. Then when I put it in neutral it just starts reving up higher and higher until I either pump the gas (sometimes works) or shut the car off, or just pop the clutch in 2nd or third. I think it could be the accelerator cable is getting stuck or the butterfly in the intake. Anyone seen or had a similar problem if so let me know what it was. So I know when I go to the Shop.

2nd My car is a standard trany, and It feels like sometimes when I push the clutch in its not pulling off all the way, I have spoke to the dealer 3 times allready and I just think they don't know what it is to fix it. They said thats normal. But other times when I push the clutch in it pulls completely off the engine and it shifts fine. But when it doesn't pull off all the way it dosn't feel like a nice smooth shift. Almost like the syncros are not lining up.

If any one knows anything about my 2 issues please help me figure them out, thanks.
Brian
US

kinkyllama · Post by **kinkyllama** » Wed Aug 03, 2005 11:37 pm

well i have the same car and have not had any of these problems. My clutch has been slipping latly but thats it

Brian5475E · Post by **Brian5475E** » Thu Aug 04, 2005 12:33 am

sounds like a TPS manfunction, or most likley the ISC motor

04aveohb · Post by **04aveohb** » Thu Aug 04, 2005 2:35 am

exactly what he said^^

lanos rider · Post by **lanos rider** » Thu Aug 04, 2005 10:04 am

give us more information like when was the last time u change the o2 sensor
did u change the fuel pump lately ..... when the last time did u scan it ...
did i wash the engine lately (it some times could be from it) .....
did u install any thing new to the car ... keep us in the pic's good luck

Mario · Post by **Mario** » Thu Aug 04, 2005 1:11 pm

lanos rider wrote:give us more information like when was the last time u change the o2 sensor
did u change the fuel pump lately .....

He has a car that is < 2 years old... so unless he did some mods on the car, why not insist on getting these problems covered under warranty... I think these car are even backed with a 7 yr / 100kmiles warranty in USA.

MMamdouh · Post by **MMamdouh** » Thu Aug 04, 2005 3:28 pm

i got the revving issue before on my lanos, the car idles at 3000 RPM.

that turned out to be a faulty TPS sensor (throttle position sensor) also check your throttle cable to make sure it is not jammed or sharply twisted. BTW my faulty TPS did not trigger a CEL.

also check the IAC (idling air controller) if it is dirty and/or jammed it could cause idling sped issues.

as for the clutch... not really sure, maybe you need to bleed it or so but i am not 100% sure of the problem.

MMamdouh

bsharon · Post by **bsharon** » Thu Aug 11, 2005 8:17 pm

OK I took it to the dealer, because I havn't put any kind of mods on it yet. I havn't changed anything or had to replace anything. I havn't washed the engine either. Well I took it in and They told me that there was a note from Suzuki stating a similar problem reported. So they said they would have to re-burn the computer chip and or reprogram it. So I was all happy. Then I picked it up yesterday, and it seemed ok for a min. Then when I got near my house it started again. With the RPM's staying at a high rev and also climbing up on it's own. So I'm pissed. I have to call them back tomorow. I know that my cable it not getting jammed. I can tell because I move it and it is free moving. Should I mension that thing about the TPS. Thats what it sounds like is the problem. well thanks for the help. Keep me posted on what you think and I will do the same on what I find out. Just incase it ever happens to your Forenza/Lacetti you will know what it is. thank all of you crazy mo-fuckers. later.

Brian

bsharon · Post by **bsharon** » Thu Aug 11, 2005 8:25 pm

They told me my clutch feels fine. It just seems to not be shifting smooth. I will make them let me drive another to see if it feels the same as another new one. I might not feel right, because the other problem thats going on. Because when I start out and push in the clutch when I shift from 1st to 2nd. the Rev's are staying up so when I pull on the shifter from 1st to 2nd it feels like i'm kinda forcing it in. It's not grinding and it's not to hard to pull in it just doesn't feel right. Then when I have to let the clutch out, I either have to wait a while for the rev's to go down or just let out the clutch and that drops the rev's down of course. But I know thats not good for it.

But I really do think its a sensor. because I can turn the car off while it's f-ing up and then turn it back on like 10 min later and the engine just starts reving up on its own again. dam thing. anyway. Hope they can fix it, because I have a CAI and a nice muffler that I want to put on. I just want to make sure that it's running good before I do.

Is an aftermarket muffler going to void my warranty?

MMamdouh · Post by **MMamdouh** » Thu Aug 11, 2005 9:10 pm

one of two things man... either a Throttle position sensor or an Intake air controller.

MMamdouh

tango · Post by **tango** » Fri Aug 12, 2005 6:04 am

A good place to check out a car before you buy is CarSurvey. What I found out there is that the Optra and its variants often suffer from TPS issues. Quite likely this is in fact your problem as everybody else alluded to.

Post by **PrecisionBoost** » Thu Aug 18, 2005 12:01 am

It sounds to me like a Idle Air control valve issue.

I've been screwing around with two different ECU's and somewhere in the middle of fooling around with my SAFC I messed up the idle settings.

So now when I start the car it brings the idle up to 3000RPM.... even while driving.... it really bugs me.... but I don't have time to fix it.

I tried a quick "idle learn procedure" but for some reason it won't work.

Perhaps my manual has left out a step because it didn't do what it was supposed to.

I even manually changed the IAC motor position so that it would idle at 900 RPM but the damned ECU changed it back up to 3000 RPM the next time I started the car.

I've noticed that the IAC setup was screwed up to start with.... in the winter the car would idle high (3500RPM) until I drove about a block and then it would settle down.

I also noticed that during throttle let off the RPM's take a while to come down...... I have traced this to an IAC issue.

If you partially block the IAC the throttle response is way better... very quick engine RPM deceleration.

So................ I think that the new Idle air control setup on the DELPHI management system just plain sucks.

I'm really really tempted to make my own IAC circuit based upon RPM, TPS, Speed Sensor and Coolant temp.

Basicly the Idle air controller is just a large needle like end that moves back and fourth depending on how much air the ECU want's to bypass the throttle butterfly.... the more the needle moves away.... the more air it lets in.

There is a little stepper motor that controls this position and it's triggered by the ECU.

Anyways.... I'm gettting too technical..... perhaps you should tell the dealership to look at the IAC setup.

MMamdouh · Post by **MMamdouh** » Thu Aug 18, 2005 12:06 pm

reminds me with the time when i had a busted TPS sensor... the ECU got no sinal from the TPS so it set the idle at 3000 RPM... this could be a TPS isuue rather than an IAC as the IAC positions itself accoring to the signal it gets from the ECU.

no matter how hard you tru with the IAC you won't get anywhere till the TPS is working fine or at least make sure of that... OK the IAC sets the idling speed according to many variables (coolant temp, A/C operational state,.....) but if the TPS is bad then the ECU goes to a fail safe mode and set the idling to 3000 RPM which is somewhat similar to your case.

don't drop off the TPS checking from your diagnosis.

MMamdouh

woo · Post by **woo** » Thu Aug 18, 2005 2:54 pm

ever had a stuck throttle or a sticky throttle cable?? It may sound a little far fetched but it has happened to my brother a fey times

Post by **PrecisionBoost** » Thu Aug 18, 2005 10:34 pm

My SAFC II shows the TPS signal voltage as well as throttle position by percentage so I know my TPS is working just fine.

I still can't get the damned thing to learn the idle position.... I have three different manuals with three different idle learn procedures and none of them work!

This is really starting to piss me off.... I would have thought that the GM Techline manual would have the "correct" procedure but now I'm wondering if any of them are correct.