Siena1.6- ECU problem?

nitinbhag · 6th April 2006, 14:12

My 5 year old Fiat Siena 1.6 has been giving problems for the past week. The engine simply stalls after driving 10+ KM and doesnt start after that. Let it cool down for an hour and it starts again and lives for another 10 odd KM.
The first time this happened (last week) I had the car towed to Sundaram. They checked it, said the ECU had some errors and they have fixed it. The car also underwent 45K km service. Picked it on Monday morning and it stalled again in the afternoon. Back to Sundaram gargae after it cooled down. Now they say ECU needs to be changed!! The errors came up again. Some self-check and error-fix algorithm is not working.

I dont know enough about ECUs and the Sundaram guy's explanations were not convincing enough to blow 10K+ on.
Can the experts help diagnose this:
Does ECU get affected by normal engine heat?
Do ECUs have a usable life? 5 years?

The car now does <10km runs the past few days.

Thanks

ajmat · 6th April 2006, 14:45

I suggest you look at the mass air flow sensor - these usually go. These tell the ecu to add more fuel based on the air drawn in. More over here

http://www.autoshop101.com/forms/h34.pdf

Try going to a fuel systems specialist like Bosch Auto service

mclaren1885 · 6th April 2006, 17:49

I suggest u speak to psycho , he might know what exactly could be wrong .. He is great with ECU's ..

Psycho · 6th April 2006, 18:52

It sounds so much like a fuel problem(pump or injectors), but the 10 mins still bothers me.

Can you confirm does it jerk when it stops???

Ajmat, I think the Siena's came with MAP's and not MAF's.

v1p3r · 6th April 2006, 21:21

Reminds me of the ice-cream allergy. Could be vapour lock...

jkdas · 6th April 2006, 21:38

Quote:

Originally Posted by v1p3r

Reminds me of the ice-cream allergy. Could be vapour lock...

yah Ice-cream one! wher did I read abt this?

Mpower · 6th April 2006, 22:25

It appears that the ECU is shutting down the car to safeguard something. They need to figure out that something.

Find out from Sundaram what error codes it threw and what exactly did they fix ?

deepakhon · 7th April 2006, 06:19

If you look at posts in paliousersindia group, you will know for sure that there is a person called Mr. Lohit at RS Motorcrafts, official Bosch service center on Hosur road. He is very competent with these kind of issues and they have an analyser for Palio in their service center. Apparently he has solved some ECU issues with Palios. Maybe, you can take this up with them.

nitinbhag · 8th April 2006, 19:13

Quote:

Originally Posted by Psycho

Can you confirm does it jerk when it stops???

Yes.. it starts jerking while running and then the engine dies.. after a few minutes, if I try to start it, the engine fires for a few seconds and then dies.. let it cool for an hour or so and it runs long enough to drive for around 10 KM..

@Mpower.. I tried but the Sundaram guys do not seem to be knowledgeable enough to discuss the error codes!!.. All the good guys have moved to Merc or GM service in Sundaram.

drpullockaran · 9th April 2006, 14:31

It does look like its an ECU problem and most probably with the cooling of some chip within the ECU. If the ECU is opened up you might find an extremely dry heatsink compound on one of the IC's inside the unit. Chip level servicing which is there in bangalore should help you out. I came to this inference because of the 10km normal drive you mentioned. If it was a malfunctioning sensor the problem would be there from the very start irrspective of whether the engine was hot or cold. One simple thing you could do is to remove the connection of the Oxygen sensor to rule out a shorted lambda sensor giving wrong signals to the ECU to process.The best option is to swap the ECU with another one as suggested in previous posts by another member Nitin. Bye and wear your seatbelts.

MexXxentric · 9th April 2006, 14:48

hi nitin,

The errors stored in the ECU can be read in the analyser.
this would possible spel out wats wrong with ur car.
the analyser is not tat much techi.
U can understand it operation if u r there in the test rig.

Drive safe

SREE

nitinbhag · 10th April 2006, 14:32

Took the car today to Bosch - RS Motorcrafts.. Lohit and Sujay attended to it.
They connected the analyser, found an error: P0170 - Mixture adaptation - Less than minimum. They reset the ECU to default values and told me to drive around.

On the way back from Bosch, car STALLED AGAIN after 8-10 km.. Similar problem as earlier. Engine started jerking and died. Now its on the road and cooling down. Am sending the car back to Bosch now.

I have a print of the analysis report. If anybody is interested I can email a scanned copy. Pl PM me email address.

Psycho · 11th April 2006, 13:26

With the engine code it looks like Ajmat was right on target, please check if your map sensor vaccum pipe has come off / is damaged. If not please replace with another map sensor and try.

I am quite sure that the palio's have a Map Sensor, else check MAF sensor if it is covered with dirt, in that case please wash with petrol and wipe dry, do take care that there are no deposits before you fit it back.

Google jindabad

ajmat · 11th April 2006, 13:38

Quote:

Originally Posted by Psycho

With the engine code it looks like Ajmat was right on target, please check if your map sensor vaccum pipe has come off / is damaged. If not please replace with another map sensor and try.

Same thing happened with my cousins Merc E220 in the UK - merc sepecialist could not figure out. Checked a few BB's and all came to these conclusion

nitinbhag · 11th April 2006, 15:34

It is indeed MAP in the Siena..
In engine running condition the MAP value does read correctly at 314 hPa so the vacuum pipe is probably OK. Will ask the Bosch folks to check it anyway.
Psycho, Ajmat - if you could PM me your email address I can send you the complete report.

6th April 2006, 14:12	#1
nitinbhag BHPian Join Date: Mar 2005 Location: Singapore Posts: 262 Thanked: 2 Times	Siena1.6- ECU problem? My 5 year old Fiat Siena 1.6 has been giving problems for the past week. The engine simply stalls after driving 10+ KM and doesnt start after that. Let it cool down for an hour and it starts again and lives for another 10 odd KM. The first time this happened (last week) I had the car towed to Sundaram. They checked it, said the ECU had some errors and they have fixed it. The car also underwent 45K km service. Picked it on Monday morning and it stalled again in the afternoon. Back to Sundaram gargae after it cooled down. Now they say ECU needs to be changed!! The errors came up again. Some self-check and error-fix algorithm is not working. I dont know enough about ECUs and the Sundaram guy's explanations were not convincing enough to blow 10K+ on. Can the experts help diagnose this: Does ECU get affected by normal engine heat? Do ECUs have a usable life? 5 years? The car now does <10km runs the past few days. Thanks
	() Thanks

6th April 2006, 14:45	#2
ajmat Team-BHP Support Join Date: Feb 2004 Location: Bangalore Posts: 14,866 Thanked: 27,981 Times View My Garage	I suggest you look at the mass air flow sensor - these usually go. These tell the ecu to add more fuel based on the air drawn in. More over here http://www.autoshop101.com/forms/h34.pdf Try going to a fuel systems specialist like Bosch Auto service
	() Thanks

6th April 2006, 17:49	#3
mclaren1885 BANNED Join Date: Jul 2005 Location: Bangalore (the city of modded cars) !! Posts: 4,820 Thanked: 45 Times View My Garage Infractions: 0/1 (10)	I suggest u speak to psycho , he might know what exactly could be wrong .. He is great with ECU's ..
	() Thanks

6th April 2006, 18:52	#4
Psycho Senior - BHPian Join Date: Jul 2004 Location: Bangalore Posts: 1,043 Thanked: 110 Times View My Garage	It sounds so much like a fuel problem(pump or injectors), but the 10 mins still bothers me. Can you confirm does it jerk when it stops??? Ajmat, I think the Siena's came with MAP's and not MAF's.
	() Thanks

6th April 2006, 21:21	#5
v1p3r Senior - BHPian Join Date: Feb 2005 Location: BLR / DXB / LON Posts: 5,334 Thanked: 6,896 Times View My Garage	Reminds me of the ice-cream allergy. Could be vapour lock...
	() Thanks

6th April 2006, 22:25	#7
Mpower Senior - BHPian Join Date: Mar 2005 Location: Bangalore Posts: 10,409 Thanked: 1,730 Times View My Garage	It appears that the ECU is shutting down the car to safeguard something. They need to figure out that something. Find out from Sundaram what error codes it threw and what exactly did they fix ?
	() Thanks

7th April 2006, 06:19	#8
deepakhon Senior - BHPian Join Date: Oct 2004 Location: Bangalore Posts: 1,441 Thanked: 65 Times	If you look at posts in paliousersindia group, you will know for sure that there is a person called Mr. Lohit at RS Motorcrafts, official Bosch service center on Hosur road. He is very competent with these kind of issues and they have an analyser for Palio in their service center. Apparently he has solved some ECU issues with Palios. Maybe, you can take this up with them.
	() Thanks

9th April 2006, 14:31	#10
drpullockaran BHPian Join Date: Jun 2005 Location: ERNAKULAM Posts: 962 Thanked: 385 Times	Ecu problems! It does look like its an ECU problem and most probably with the cooling of some chip within the ECU. If the ECU is opened up you might find an extremely dry heatsink compound on one of the IC's inside the unit. Chip level servicing which is there in bangalore should help you out. I came to this inference because of the 10km normal drive you mentioned. If it was a malfunctioning sensor the problem would be there from the very start irrspective of whether the engine was hot or cold. One simple thing you could do is to remove the connection of the Oxygen sensor to rule out a shorted lambda sensor giving wrong signals to the ECU to process.The best option is to swap the ECU with another one as suggested in previous posts by another member Nitin. Bye and wear your seatbelts.
	() Thanks

9th April 2006, 14:48	#11
MexXxentric BHPian Join Date: Feb 2005 Location: Trivandrum Posts: 248 Thanked: 11 Times	hi nitin, The errors stored in the ECU can be read in the analyser. this would possible spel out wats wrong with ur car. the analyser is not tat much techi. U can understand it operation if u r there in the test rig. Drive safe SREE
	() Thanks

10th April 2006, 14:32	#12
nitinbhag BHPian Join Date: Mar 2005 Location: Singapore Posts: 262 Thanked: 2 Times	Took the car today to Bosch - RS Motorcrafts.. Lohit and Sujay attended to it. They connected the analyser, found an error: P0170 - Mixture adaptation - Less than minimum. They reset the ECU to default values and told me to drive around. On the way back from Bosch, car STALLED AGAIN after 8-10 km.. Similar problem as earlier. Engine started jerking and died. Now its on the road and cooling down. Am sending the car back to Bosch now. I have a print of the analysis report. If anybody is interested I can email a scanned copy. Pl PM me email address.
	() Thanks

11th April 2006, 13:26	#13
Psycho Senior - BHPian Join Date: Jul 2004 Location: Bangalore Posts: 1,043 Thanked: 110 Times View My Garage	With the engine code it looks like Ajmat was right on target, please check if your map sensor vaccum pipe has come off / is damaged. If not please replace with another map sensor and try. I am quite sure that the palio's have a Map Sensor, else check MAF sensor if it is covered with dirt, in that case please wash with petrol and wipe dry, do take care that there are no deposits before you fit it back. Google jindabad
	() Thanks

11th April 2006, 15:34	#15
nitinbhag BHPian Join Date: Mar 2005 Location: Singapore Posts: 262 Thanked: 2 Times	It is indeed MAP in the Siena.. In engine running condition the MAP value does read correctly at 314 hPa so the vacuum pipe is probably OK. Will ask the Bosch folks to check it anyway. Psycho, Ajmat - if you could PM me your email address I can send you the complete report.
	() Thanks