[Krystian Leńczuk]

Hey there everyone!

To make reading through my problem a bit easier i will split it into few points what i observed before car suddenly stopped and what i changed and checked prior to that.

I own Tiburon from 2003, vvt 4 cyl. And sorry for my English just in case, its not my main language.

Car lost abit of power while accelerating especially below 3k rpm.
After 2/3 days suddenly engine died after like 1 km. Weird thing that ive spotted/heard was constant clicking noise coming out of stepper motor on intake. Took it out,cleaned it was able to succesfully drive for like 2/3 km and then it died again.
Another thing is after it dies, i cant start it unless i wait 10/15 mins.
Also rpm at idle isnt smooth- varies alot and sometimes revs itself on idle up to 2K- after pressing gas pedal it drops back to normal.

So far i've checked and/or replaced:

replaced MAF
replaced stepper motor
replaced camshaft sensor
checked and replaced fuel filter just in case

Double checked entire intake up to TB with each hose - no air leaks.
Checked plugs, all are fine.
Coil and cables were replaced 5 months ago.
Alternator and Battery were replaced 2 months ago. both works perfectly even when car sat for like 2 weeks with -15 cold.

Im totally lost what to do now. What to check or what it could be.
Happend totally suddenly. Would be great if anyone could help me out at what else i could look or if someone happend to have similar symptoms before.

 

[chase206]

Did you use OEM sensors or high quality brands from a legitimate vendor? Such as Siemens, Mando, NTK or Denso? All other brands will not work including a reputable brand like Bosch.

When the car dies can you verify that you still have consistent spark? If spark is inconsistent it's likely your crank angle sensor that is flaky. Often times the crank sensor works long enough to drive down the road and when temperatures rise the sensor quits working and you must wait 10-15min for the engine too cool down before it will restart. Without a consistent quality crank signal you will not have consistent spark. If you have headers you need to wrap them to protect the crank sensor from melting and failing prematurely. Replace with only Siemens, NTK or Mando brands for this sensor position.

 

[Krystian Leńczuk]

Did you use OEM sensors or high quality brands from a legitimate vendor? Such as Siemens, Mando, NTK or Denso? All other brands will not work including a reputable brand like Bosch.

When the car dies can you verify that you still have consistent spark? If spark is inconsistent it's likely your crank angle sensor that is flaky. Often times the crank sensor works long enough to drive down the road and when temperatures rise the sensor quits working and you must wait 10-15min for the engine too cool down before it will restart. Without a consistent quality crank signal you will not have consistent spark. If you have headers you need to wrap them to protect the crank sensor from melting and failing prematurely. Replace with only Siemens, NTK or Mando brands for this sensor position.

All sensors Ive changed were OEM ( tried different one and it did threw code ) . I'm completely lost what else it could be. Today managed to turn it on, but engine started revving up to 2K at idle and had to push slightly gas pedal to drop it back to its "average", but then it again started revving (not to mention rpm were inconsistent). No codes either.
Ordered in meantime new coil since it doesn't cost that much and it wouldn't hurt changing it.
Also noticed again that when it suddenly shuts of - stepper motor/iacv is buzzing.

 

[Charlie-III]

OK, to start with, when it dies and you have to wait 10-15 minutes before it will start again makes me think an electrical issue due to heat soak. Things like ignition coils (you replaced), sensors (you did cam, maybe need to do crank), etc.

Next time it dies, open the hood and see if it cools down faster allowing a sooner restart.

Also, can you read sensor data? I'm not sure if you have OBDII and a scanner. I am getting at your ECT (engine coolant temperature) sensor. After the car has been sitting a few hours, check the ambient temperature where the car is (in a garage, outside, whatever) and the ECT value. They should be very close to each other. If wildly different, your fueling/mixture will be off.

 

[Krystian Leńczuk]

OK, to start with, when it dies and you have to wait 10-15 minutes before it will start again makes me think an electrical issue due to heat soak. Things like ignition coils (you replaced), sensors (you did cam, maybe need to do crank), etc.

Next time it dies, open the hood and see if it cools down faster allowing a sooner restart.

Also, can you read sensor data? I'm not sure if you have OBDII and a scanner. I am getting at your ECT (engine coolant temperature) sensor. After the car has been sitting a few hours, check the ambient temperature where the car is (in a garage, outside, whatever) and the ECT value. They should be very close to each other. If wildly different, your fueling/mixture will be off.

Changed cam and crank too (today).
After some thoughts could it be possibly fuel pump dying ?
I remember it had some problems while ago while starting. I had to crank it 2/3 times before engine would start.
About pump it's working but maybe not as it should or the pressure is too low ?
Still that revving all by itself up to 2k is weird . Never happened before.
All that's left what I can do outside is changing fuel pump (entire assembly ) coil and TPS (althrough it never had any problems ).
And about ECT sensor I've read some topics that people had some weird things happening when sensor was faulty.
It's the one close to thermostat (if so it was changed with thermostat about like 4/5 months ago as well) or one on front below camshaft valve (the one with little wire extension ).

 

[Tim Tiburon 2007 V6 2.7]

Changed cam and crank too (today).
After some thoughts could it be possibly fuel pump dying ?
I remember it had some problems while ago while starting. I had to crank it 2/3 times before engine would start.
About pump it's working but maybe not as it should or the pressure is too low ?
Still that revving all by itself up to 2k is weird . Never happened before.
All that's left what I can do outside is changing fuel pump (entire assembly ) coil and TPS (althrough it never had any problems ).
And about ECT sensor I've read some topics that people had some weird things happening when sensor was faulty.
It's the one close to thermostat (if so it was changed with thermostat about like 4/5 months ago as well) or one on front below camshaft valve (the one with little wire extension ).

Hi Krystian,
My 2007 V6TS is doing the same thing !!! Trouble starting, then running rough, then idling at 2 to 3,000 rpm. I changed the spark plugs to he original NGK R PF5N 11, but it still happens. When it stalls, I have to wait a long time until it starts again and it feels like an electrical problem. My stepper motor on the IACV is also buzzing. I am thinking it may be the BCM or ECT.
I have ordered a CPS and a IACV first. Please let me know how it goes and I will do the same.

 

[Krystian Leńczuk]

Hi Krystian,
My 2007 V6TS is doing the same thing !!! Trouble starting, then running rough, then idling at 2 to 3,000 rpm. I changed the spark plugs to he original NGK R PF5N 11, but it still happens. When it stalls, I have to wait a long time until it starts again and it feels like an electrical problem. My stepper motor on the IACV is also buzzing. I am thinking it may be the BCM or ECT.
I have ordered a CPS and a IACV first. Please let me know how it goes and I will do the same.

Hey there !

So at this point replaced nearly every sensor (along with oil temperature one that came y'day since connector pretty much crumbled to pieces).
Crank, camshaft, iacv , maf were changed, replaced entire fuel pump with filters (since I thought that it could be fuel issue ).
Car starts pretty much instantly after sitting in old for like 3rd week but sadly problem isn't solved.

Last thing that's left to check is the coil, and spark plugs again (or maybe injectors , seen somewhere post that one guy had similar problems , no cel , sensors fine and car kept doing similar stuff like mine does).

I'm completely lost at this point.

 

[Tim Tiburon 2007 V6 2.7]

I am going to get it scanned as I don't own a scanner and see if that leads anywhere. I am also going to check the BCM as another post fixed their issue replacing the BCM. Will let you know.

 

[Krystian Leńczuk]

I am going to get it scanned as I don't own a scanner and see if that leads anywhere. I am also going to check the BCM as another post fixed their issue replacing the BCM. Will let you know.

As of today replaced entire fuel pump with filters and spark plugs.
Still it revs itself up to 2k(probably not to shut down completely ) while I keep it at idle (700 ish) it runa really rough and eventually shut down. All that left for me to check is TPS (will replace tommorow along with TB )

 

[Tim Tiburon 2007 V6 2.7]

Changed the Cam sensor today. It starts fine now and idles well, but after about 3 minutes it revs to about 3,000 and I can hear the IACV pulsing and sending the revs up and down. Just read a new post with the same symtoms and he has changed his injectors. I have asked him if that was the main problem and will let you know.

 

[Krystian Leńczuk]

Changed the Cam sensor today. It starts fine now and idles well, but after about 3 minutes it revs to about 3,000 and I can hear the IACV pulsing and sending the revs up and down. Just read a new post with the same symtoms and he has changed his injectors. I have asked him if that was the main problem and will let you know.

Mine still sitting outside , it stars but closer to the default idle, more chance it will die immediately.
Ordered one more Crank sensor , since previous one was damaged (broken casing, and oil spilled into connector). And one I have now is from Delphi.
But what I've found y'day new one was slightly bent. Ordered brand new one from NTK as suggested on the forum and will see.
About injectors I have spare rail with set of injectors so will eventually tommorow swap it to see if anything changes.
Still no CELs , eventually it flashes when it's about to die.
Also changed TPS , didn't help at all.
So all that's left it's either faulty sensor still and readings are off , or that injectors

 

[chase206]

If the ECU isn't receiving a clean crank signal it will misfire it it won't fire at all. The Delphi brand is generally good quality for US domestic vehicles but I don't know if anyone using Delphi for our crank position sensor. NTK and Siemens are the OEM trusted brands for that sensor position.

A flashing CEL indicates a misfire. That's the ECU trying to alert you that your knock sensors are detecting knock. Likely due to inconsistent or a weak crank signal. Otherwise your ECU is intermittently losing crank signal. With key on engine off the CEL will be lit up. So if the ECU thinks the motor is not turning due to lack of crank signal that light will come on.

 

[Krystian Leńczuk]

If the ECU isn't receiving a clean crank signal it will misfire it it won't fire at all. The Delphi brand is generally good quality for US domestic vehicles but I don't know if anyone using Delphi for our crank position sensor. NTK and Siemens are the OEM trusted brands for that sensor position.

A flashing CEL indicates a misfire. That's the ECU trying to alert you that your knock sensors are detecting knock. Likely due to inconsistent or a weak crank signal. Otherwise your ECU is intermittently losing crank signal. With key on engine off the CEL will be lit up. So if the ECU thinks the motor is not turning due to lack of crank signal that light will come on.

That's why I've ordered NTK one and OEM one to see if it will go away after replacing it. After checking through literally everything , sensor seemed only to be broken in the end , I can't even recall when I ripped so many things out of this car to find issue haha 😆

Edit 09.03
After changing ignition wires suddenly it's dropping p1507 and p1505 cels.
Also after disconnecting iacv I can hear little buzzing sound from around ignition coil location.
I'm at the brink of dropping that car at the junkyard slowly.

 

[Krystian Leńczuk]

BUMP/UPDATE

Changed IACV since current one after "locking" and buzzing itself damaged magnet inside. and got another crank sensor to check if i had just bad luck with it.
still nothing changed. it cranks but wont start. Has spark (arcing properly ) fuel getting into the lines. im completely lost at this point.

 

[chase206]

Spark is a good sign that the crank angle sensor is working. I wouldn't bother buying another one just to throw parts at the problem. Are you certain that your injectors are firing too? Are your spark plugs coming out wet or dry after attempting to crank the motor over?

Have you done a compression test at all? Have you inspected your timing belt or that your crank/cams are in time with each other? I wonder if your timing belt skipped a few teeth and that explains the loss of power. If it skips any further you'll likely lose compression to the point it won't start at all. Common culprit is a failing timing belt tensioner on the 2.7L but I don't remember if your 2.0L has a hydraulic or manual tensioner.

 

[Krystian Leńczuk]

Spark is a good sign that the crank angle sensor is working. I wouldn't bother buying another one just to throw parts at the problem. Are you certain that your injectors are firing too? Are your spark plugs coming out wet or dry after attempting to crank the motor over?

Have you done a compression test at all? Have you inspected your timing belt or that your crank/cams are in time with each other? I wonder if your timing belt skipped a few teeth and that explains the loss of power. If it skips any further you'll likely lose compression to the point it won't start at all. Common culprit is a failing timing belt tensioner on the 2.7L but I don't remember if your 2.0L has a hydraulic or manual tensioner.

Plugs are wet, when taken out , I can smell gasoline on them. I thought maybe when previous faulty sensor didn't run as expected it flooded engine entirely. Since I don't have oscilloscope, done test with screwdriver (to check if they click and all 4 of them does ).
All that's left to check probably is immobilizer (althrough key fob and everything worked, and works as it is today). Read through entire forum to seek some kind of new idea or some fresh view but I'm completely out of ideas.

I guess all that's left to check is the timing belts, but it would be really weird with fairly fresh belts with under 2k km on them (along with tensioners since I replace entire set always along with water pump and everything ).

On Monday will drop car at the mechanic since I can't resurrect it at this point and all I could check or change I did.
Thanks for all the ideas tho !

 

[cplangreder]

Hey there everyone!

To make reading through my problem a bit easier i will split it into few points what i observed before car suddenly stopped and what i changed and checked prior to that.

I own Tiburon from 2003, vvt 4 cyl. And sorry for my English just in case, its not my main language.

Car lost abit of power while accelerating especially below 3k rpm.
After 2/3 days suddenly engine died after like 1 km. Weird thing that ive spotted/heard was constant clicking noise coming out of stepper motor on intake. Took it out,cleaned it was able to succesfully drive for like 2/3 km and then it died again.
Another thing is after it dies, i cant start it unless i wait 10/15 mins.
Also rpm at idle isnt smooth- varies alot and sometimes revs itself on idle up to 2K- after pressing gas pedal it drops back to normal.

So far i've checked and/or replaced:

replaced MAF
replaced stepper motor
replaced camshaft sensor
checked and replaced fuel filter just in case

Double checked entire intake up to TB with each hose - no air leaks.
Checked plugs, all are fine.
Coil and cables were replaced 5 months ago.
Alternator and Battery were replaced 2 months ago. both works perfectly even when car sat for like 2 weeks with -15 cold.

Im totally lost what to do now. What to check or what it could be.
Happend totally suddenly. Would be great if anyone could help me out at what else i could look or if someone happend to have similar symptoms before.

My 03, that I purchased 4 months ago was doing the exact same thing. I just put up a new post about resetting my ecm. I am not a mechanic, but luckily this solved my problem. Check out Savagescotty on YouTube about doing this. Will only cost you about 20 minutes of your time, no out of pocket cost and 10 year old could do it. I have 130,000 miles on it and now runs like new. Best of luck!

 

[Krystian Leńczuk]

My 03, that I purchased 4 months ago was doing the exact same thing. I just put up a new post about resetting my ecm. I am not a mechanic, but luckily this solved my problem. Check out Savagescotty on YouTube about doing this. Will only cost you about 20 minutes of your time, no out of pocket cost and 10 year old could do it. I have 130,000 miles on it and now runs like new. Best of luck!

Hey there !
Left my car at the mechanic and yeah, my ECU didn't put any kind of signal into injectors. So now waiting to either reflash it or change if it got damaged. Didn't expect something like that to be honest

 

[cplangreder]

Hey there !
Left my car at the mechanic and yeah, my ECU didn't put any kind of signal into injectors. So now waiting to either reflash it or change if it got damaged. Didn't expect something like that to be honest

At least you know what is happening. I hope it gets taken care of soon and that you become a happy camper again soon. Take care.

 

[Tim Tiburon 2007 V6 2.7]

Hi,
Just changed the PCV and the IACV. Seems better, but still plays up. Do you think resetting the ECM would solve it ?