Please Help On This

[ThilakR]

Hi all

Normally what are the intervals for engine tune-up for a car? I have a Daihatsu Mira 2000 year car (Auto) 660cc having problem of bad vibration and sometimes stops at the middle of the road when slowdown and take the foot off from the accelerator paddle. When switch on the AC, it is little ok.

I tuned-up the car about 4 months before due to this problem and it was fine for couple of months but started the same problem.

It looks like I have to tune-up the engine in every 3 months. Could anyone help me to find a solution please?

Many thanks

Thilak

[Crosswind]

For me it looks like there's a problem with the cooling system of the engine. The cause may be a faulty thermostat valve or a radiator fan. That's why it becomes ok when the AC is on. Keep an eye on the engine temperature indicator when the car stalls. If the indicator is not working, you may need to get that sorted out first.

Check if the fan speed is ok when the AC is off.

Edited April 19, 2012 by Crosswind

[ThilakR]

For me it looks like there's a problem with the cooling system of the engine. This may be a faulty thermostat valve or a radiator fan. That's why it becomes ok when the AC is on. Is the engine temperature indicator working fine?

Thanks for the quick respond Crosswind. Yes. Cooling system works fine. Sorry I fogot to mentioned. when I keep the foot little on the accelerator paddle problem is ok.

Regards

Thilak

[Crosswind]

If thats the case, did you clean the IACV during your tune up?

[ThilakR]

If thats the case, did you clean the IACV during your tune up?

I am sorry mate. What is IACV?

Tuneup was done by Daihatsu Agents.

Regards

Thilak

Edited April 19, 2012 by ThilakR

[NZer]

Check you plugs and leads and there is a screw that you can turn to increase the idle. This would sort your issue. The screw if located on the throttle body.

[ThilakR]

Check you plugs and leads and there is a screw that you can turn to increase the idle. This would sort your issue. The screw if located on the throttle body.

Thanks NZer. I will try to locate this screw. Is it ok for me to do so since I am not familiar on this? Will I totally screw up the tuning?

If this the issue, why it change so frequently? Other cars I used did not have this issue.

Any idea mate?

Regards

Thilak

[Crosswind]

I am sorry mate. What is IACV?

Tuneup was done by Daihatsu Agents.

Regards

Thilak

Idle Air Control Valve

[The Stig]

Thanks NZer. I will try to locate this screw. Is it ok for me to do so since I am not familiar on this? Will I totally screw up the tuning?

If this the issue, why it change so frequently? Other cars I used did not have this issue.

Any idea mate?

Regards

Thilak

Dont do this, it is not a very smart idea. Yes it will most probably sort out your idle stalling issue but its not the proper solution. Idle speed screws dont turn by them selfs (most of the time), therefore if the screw was in the same position it is now and it worked perfectly well in this position before and now it doesnt work only means that the problem isnt with the idle rpm. stupid thing to do, you would only be bypassing the actual problem for another short period.

The actual problem IMHO could be with your injectors (im guessing it is EFI ? ), injectors get clogged up over time cause of unfiltered particle in the fuel and over time they get stuck on the injector nozzles which lowers the amount of fuel being send to your engine. Best thing to do is to use an "injector cleaning fluid", you can get them from most autoparts dealers and all you have to do is measure the right volume (according to the specifications of the bottle) and pour it into the gas tank

BTW hows the state of your air filter ? it could also be another reason

[ThilakR]

Dont do this, it is not a very smart idea. Yes it will most probably sort out your idle stalling issue but its not the proper solution. Idle speed screws dont turn by them selfs (most of the time), therefore if the screw was in the same position it is now and it worked perfectly well in this position before and now it doesnt work only means that the problem isnt with the idle rpm. stupid thing to do, you would only be bypassing the actual problem for another short period.

The actual problem IMHO could be with your injectors (im guessing it is EFI ? ), injectors get clogged up over time cause of unfiltered particle in the fuel and over time they get stuck on the injector nozzles which lowers the amount of fuel being send to your engine. Best thing to do is to use an "injector cleaning fluid", you can get them from most autoparts dealers and all you have to do is measure the right volume (according to the specifications of the bottle) and pour it into the gas tank

BTW hows the state of your air filter ? it could also be another reason

Thanks mate. This is the car I use to take my kids to school. So I need to fix this before end of this school holidays. Do you know a good place to take the car and get this done and the tuneup if it is necessary. I am in Gampaha but I could come to colombo if there is any good place.

I remember those who did engine tuneup said they cleaned the injectors and throttle body too.

BTW I checked the air filter and it is good.

Best regards

Thilak

Edited April 20, 2012 by ThilakR