[spacefugitive]

Originally Posted by mohit333

Check fuel pump motor. It is housed in the fuel pump assembly. If the motor is weak, it does not throw out fuel at the required pressure and under fully loaded conditions, the fuel supply is limited.

The entire assembly will cost you approx Rs.10-15000. Instead just tell your mechanic to open up the fuel pump assembly and try another motor. The motor is of Bosch make and costs Rs 1500-2000 here at the Mumbai Bosch authorised outlets.

Hi Mohit,
Hope youre still subscribed, I wanted to know wether you or anyone you know has successfully made motor switch for a siena or a palio. My service advisor (the only tata motors employee I prefer to interact with) said that he has come across someone who did the same (doesnt remember the make of the motor though) but after this the fuel supply was cut off altogether. If you have some more information for this, It would be really encouraging.

Thanks,
Aninda.

[CPH]

I don't think that it is throttle body at all.

I wonder whether it is the ECU since yours is a 2000. I take it you have one of the Marelli ECUs. They had basically 2 different ones on this engine confuguration.

Is it the small one with the connectors on the top?

If so what HW number (3 digits) does it have?

[spacefugitive]

Thanks CPH for your reply ... Again .. I dont have this information for you yet. I will try and get this to you by next week.

Meanwhile I found a a very interesting thread in another forum which describes the same Issue : There are a couple of solutions there -
Technical: Siena Does Not Start when Hot - The FIAT Forum
It would be very helpful if someone could validate these..

Again ... I cannot thank you enough for your help.

[spacefugitive]

Any other tips? I am going to the service center tommorrow to take these ideas to the mechanics ... any other ideas are welcome.

[spacefugitive]

Originally Posted by mohit333

Check fuel pump motor. It is housed in the fuel pump assembly. If the motor is weak, it does not throw out fuel at the required pressure and under fully loaded conditions, the fuel supply is limited.

The entire assembly will cost you approx Rs.10-15000. Instead just tell your mechanic to open up the fuel pump assembly and try another motor. The motor is of Bosch make and costs Rs 1500-2000 here at the Mumbai Bosch authorised outlets.

Would it be possible to check this with a fuel pressure gauge when this happens? Is it easy enough to connect a fuel pressure gauge for a newbie when this happens? Is it possible to DIY?

How much would a fuel pressure gauge cost?

[mohit333]

Originally Posted by spacefugitive

Hi Mohit,
Hope youre still subscribed, I wanted to know wether you or anyone you know has successfully made motor switch for a siena or a palio. My service advisor (the only tata motors employee I prefer to interact with) said that he has come across someone who did the same (doesnt remember the make of the motor though) but after this the fuel supply was cut off altogether. If you have some more information for this, It would be really encouraging.

Thanks,
Aninda.

Sorry wasnt receiving the updates on this thread. Would you elaborate a little on the motir switch? I didnt get you.

Originally Posted by spacefugitive

Would it be possible to check this with a fuel pressure gauge when this happens? Is it easy enough to connect a fuel pressure gauge for a newbie when this happens? Is it possible to DIY?

How much would a fuel pressure gauge cost?

My mechanic checked it manually as he was comparing the motor with another spare that he had with him. Try visiting the Bosch Service Centre personally and speaking to the guys there.

[spacefugitive]

Originally Posted by mohit333

Sorry wasnt receiving the updates on this thread. Would you elaborate a little on the motir switch? I didnt get you.

My TATA/FIAT service advisor tells me that someone had earlier tried switching out just the fuel pump motor in another Siena. He observed that this created more starting issues for that person. He was only able to operate the vehicle once the fuel pump assembly was changed with a FIAT original second hand part that he procured from somewhere.

I'd really like to know if you have come across anyone who has succesfully changed just the motor in a palio or a siena, because that would mean this person did not use a good motor or the motor replacement work was not done properly.

*Update*
I visited the BOSCH service center in Rajajinagar - United Motors.
They did a diagnostic and found that everything checks out as it should - obviously the problem was not happening then. They did their checks and found that most things were as they should be.

They had a hunch that a problem like this would be because of bad electricals or electronics. They found that there were some groundings etc .. were not done.
They did a electrical wiring service for which they charged me Rs.1200. & did a general service. Keeping my fingers crossed!

[rmonie]

I had a similar problem on my 1.6 Adventure. Went through the whole tamasha of A55 / diagnostic scan etc. finally was advised to clean the crank position sensor & she's running fine since then. This was about a year ago & the car is still fine.

[kailashnj]

I had a similar problem in my car and it turned out to be the starter motor which does not take the load when it is hot.

I got the starter motor replaced and everything was working fine - Before the starter motor also check the battery and alternator for their capacity. Hope this helps.

Regards,
Kailash

[nutmello]

hi
i own a fiat 1.6 petrol. i have faced the similar problem.

1. battery disintegrates and will not hold any charge at all.
2. wait for 30 min or over night. that is allow the battery to reviatlise.
3. car starts without a mur mur as if nothing has happened at all.
4. din 60 and higher , battery will be helpful.
nothing much can be done. ideally very good quality battery will do.
your mechanic might say that battery is not getting charged, alternator needs to be looked into. he will even show you using a multi meter that battery is showing less than 11 v, and will even raise the throttle and will show that there is hardly any power coming to battery from alternator to charge the battery. but trust me, it is the fault of the battery.
under heavy loads ( 5 people, hot sun, ac on) the car tends to drain out the battery and also, the battery just goes for a toss. multi meters will not tell you anything in such situations.
strangely, give rest to battery, it will fire like new.
weird but true

[spacefugitive]

Thanks for your suggestions Kailash, rmonie & nutmello. I will look into these if the problems happen again.