Hi,
New here so bear with me, and hope this is in the right place.
I have a 2008 Santa Fe 2.2 CRDi auto (Australian Spec).
I have been having an issue with RPM surging that I have been trying to work through with my local Hyundai garage, but they seem to think I have an open cheque book for diagnostics without coming up with a definitive answer.
I have had the car over 2 years so know it fairly well.
Servicing is up to date, next major service in about 2 thousand KM's. Car has 125000km on the clock. It is all original - very good condition and been kept fully maintained.
This has been ongoing for the last 4 weeks..
My symptoms:
When the air temperature is cold (less than 15 degrees) the car will fluctuate the RPM when maintaining speed. So for example when I am maintaining 60km, 80km etc it feels as though the throttle is being pressed on and off really quickly. Under acceleration it is smooth. It idles perfectly. No dash lights.
Especially evident on cold starts, when car has been left overnight or all day - not always the case though. It seems more effected by ambient air temperature appose to the engine temperature.
On a nice warm day the car runs perfectly.
Can't feel the fluctuation at freeway speeds except for an unexpected reduction in revs occasionally - almost a dying feeling for it to come back again. There is a distinct lack of power at freeway speeds though, especially on slight incline when there is just no more guts left.
Tried with cruise on and off - same. However on cruise it has an inability to keep up the speed and drops too low before figuring it out, kicking down a gear and taking itself back up to speed.
Tried it in auto and switching across to manual - no change.
Numerous times now (5) it has lost all throttle power, similar to what I would expect for limp home mode. No dash lights. Car has to be restarted twice to run normal again. Then continues with the RPM fluctuation.
Eventually the car seems to settle down somewhat, although not perfect. About 30-40 mins into the journey all is slightly better.
During the RPM wildly fluctuating I have had one occasion when the engine management light flashed and the car went into limp home. The light then stayed on after restarting.
What done so far..
After the first time it died I took it to Hyundai. They spent time on diagnostics to find no fault code listed. They did find that there was new software available and downloaded onto my car.
This new software has made no difference.
Took back and fault code P0120 logged. Arranged for it to go back in for further diagnostics.
Taking the car back for this appointment is when it did the engine management light for the first time. This time the car has shown code P0120 and another for I think turbo underboost?
They referred this to Hyundai and they have suggested that the issue is with the Automatic Transaxle Electronic Control Module.
They wanted to spend time looking at the turbo, but I am not convinced this is another problem. The thing has had to cope with fluctuating use so I would report a fault as well!
They did offer taking a few more hundred $ off me to have a look, or suggested that I could try replacing the main relay for this module ($30 for part). I have ordered and replaced this relay, worth a punt.
They took the relay out to take the part number for ordering, and out back in again. The check engine light went out
When the new relay was fitted I asked them to clear the fault codes. The above codes were still shown but with a new code I think for particulate regeneration?
There is no change, when the ambient temperature is low it does exactly the same thing.
What they are suggesting next..
To spend an unspecified amount for them to try and diagnose.
Replace the Electronic Control Module (Part 9544739520) very pricey from Hyundai ($900), but OEM or used around the $300 mark. Plus fitting, but with no guarantee it will work.
My worst nightmare - electronic gremlins.
Has anyone heard of a similar issue?
Can anyone suggest the best way forward?
2 hrs of diagnostics pays for the Control Module - do I try this first?
Do I have new gaskets put on the turbo?
The fuel filter is coming up for changing - do I service it now?
I can't keep spending on diagnostics so at some point have to have a educated guess with everything crossed!
Thanks for taking the time to read.
Any help, thoughts, suggestions would be gratefully received.
Cheers.
New here so bear with me, and hope this is in the right place.
I have a 2008 Santa Fe 2.2 CRDi auto (Australian Spec).
I have been having an issue with RPM surging that I have been trying to work through with my local Hyundai garage, but they seem to think I have an open cheque book for diagnostics without coming up with a definitive answer.
I have had the car over 2 years so know it fairly well.
Servicing is up to date, next major service in about 2 thousand KM's. Car has 125000km on the clock. It is all original - very good condition and been kept fully maintained.
This has been ongoing for the last 4 weeks..
My symptoms:
When the air temperature is cold (less than 15 degrees) the car will fluctuate the RPM when maintaining speed. So for example when I am maintaining 60km, 80km etc it feels as though the throttle is being pressed on and off really quickly. Under acceleration it is smooth. It idles perfectly. No dash lights.
Especially evident on cold starts, when car has been left overnight or all day - not always the case though. It seems more effected by ambient air temperature appose to the engine temperature.
On a nice warm day the car runs perfectly.
Can't feel the fluctuation at freeway speeds except for an unexpected reduction in revs occasionally - almost a dying feeling for it to come back again. There is a distinct lack of power at freeway speeds though, especially on slight incline when there is just no more guts left.
Tried with cruise on and off - same. However on cruise it has an inability to keep up the speed and drops too low before figuring it out, kicking down a gear and taking itself back up to speed.
Tried it in auto and switching across to manual - no change.
Numerous times now (5) it has lost all throttle power, similar to what I would expect for limp home mode. No dash lights. Car has to be restarted twice to run normal again. Then continues with the RPM fluctuation.
Eventually the car seems to settle down somewhat, although not perfect. About 30-40 mins into the journey all is slightly better.
During the RPM wildly fluctuating I have had one occasion when the engine management light flashed and the car went into limp home. The light then stayed on after restarting.
What done so far..
After the first time it died I took it to Hyundai. They spent time on diagnostics to find no fault code listed. They did find that there was new software available and downloaded onto my car.
This new software has made no difference.
Took back and fault code P0120 logged. Arranged for it to go back in for further diagnostics.
Taking the car back for this appointment is when it did the engine management light for the first time. This time the car has shown code P0120 and another for I think turbo underboost?
They referred this to Hyundai and they have suggested that the issue is with the Automatic Transaxle Electronic Control Module.
They wanted to spend time looking at the turbo, but I am not convinced this is another problem. The thing has had to cope with fluctuating use so I would report a fault as well!
They did offer taking a few more hundred $ off me to have a look, or suggested that I could try replacing the main relay for this module ($30 for part). I have ordered and replaced this relay, worth a punt.
They took the relay out to take the part number for ordering, and out back in again. The check engine light went out
When the new relay was fitted I asked them to clear the fault codes. The above codes were still shown but with a new code I think for particulate regeneration?
There is no change, when the ambient temperature is low it does exactly the same thing.
What they are suggesting next..
To spend an unspecified amount for them to try and diagnose.
Replace the Electronic Control Module (Part 9544739520) very pricey from Hyundai ($900), but OEM or used around the $300 mark. Plus fitting, but with no guarantee it will work.
My worst nightmare - electronic gremlins.
Has anyone heard of a similar issue?
Can anyone suggest the best way forward?
2 hrs of diagnostics pays for the Control Module - do I try this first?
Do I have new gaskets put on the turbo?
The fuel filter is coming up for changing - do I service it now?
I can't keep spending on diagnostics so at some point have to have a educated guess with everything crossed!
Thanks for taking the time to read.
Any help, thoughts, suggestions would be gratefully received.
Cheers.