Timing Issue in ECM Controlled Maruti 800


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Hi! I have a Maruti 800 MPFi year 2008 and I'm trying to set the ignition timing. The owner manual that came with the car said it must be on 7° BTDC but it doesn't say if its on test mode (test terminal grounded on monitor coupler) or with ECM controlling it.. Anyone knows about this on Euro III model?

Thanks!
 
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Hi, I will discuss with my friend, who is a Maruthi engineer. Presently he is undergoing training and will be back after a week.
Amazed to see Maruthi 800 in Chile. Please post some photos.
 

Varun560061

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Are you using the timing gun to check this, I haven't faced this issue.

Are you trying to advance the timing ?
 
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It is indeed in the test mode. Warm up the engine before until the fan runs once then put it in the test mode. I think you can put it in test mode on cold start too but not sure.
 
Thread Starter #6
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Thanks, I will upload photos, now I don't have some recents ones..

Yes, I have a timing gun so I have tried on 7° BTDC in test mode (4-5° ungrounded) and 9° in test mode (7° ungrounded), I'm now in the last config mentioned.. I thinks when it was more retarded it lowered his mileage, it has sense anyway, but I don't feel a notable diference on car power..

I have installed a bosch red coil and 8mm plug wires currently with Denso W16EXR-U plugs at 0,9mm gap, but it must not affect the timing system..

Something I think may be interesting.. when I set the timing on 9° in test mode, it let me to close more the minimum air screw (that black screw on the throttle body) for getting 900 RPM with aprox 25% of duty cycle
 
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why do you want to change timing?
altering timing will change the whole riding quality of the car & also do not change any screw setting at throttle body as they are set by computer to give you best performance also if you want to check your timing you can get your car scanned at service station they will give you a print out of your timing & other sensors.
 
Thread Starter #8
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I just want to get the optimal setting..
the ECM just can control the IAC valve not the minimal air screw, it's set manually as a starting point from where the IAC works, if it's too open or too close the ECM can't adjust the idle speed. Maruti 800's ECM don't have a sensor of crankshaft nor camshaft, so it has no idea of where is the timing, it only can adjust it assuming that the starting position is ok. For reading the duty cycle you don't need a scanner, just a multimeter and a little of patience.. ;)
 
Thread Starter #9
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as promised.. some photos ;)






These are the most recents I have =P
sorry for bad quality.. just phone camera..

PS: still waiting for some info of timing issue, I hope you guys can get some ;)
 
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Varun560061

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Will get back to you with more information.

I could see only one pic in which I am unable to see you car, please post some more pic's.
 

Varun560061

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Your car looks cool. Thanks for posting the pic's. Are those performance cords connected to the spark plugs ?

Does the brake booster come as factory fitted equipment ?
Also please post a pic showing the pipe connecting to booster (vacuum source).
Is it from the manifold or alternator.
 
Thread Starter #14
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thanks! Yes, these cord are connected to the spark plugs, it's a nice mod, improves noticeably the engine performance, first I only change the coil, and it was almost unuseful, but with the cord it was obvious ;)

The brake booster comes from factory (are not the best brakes on the world, but I really like them, they give me a good control over the brake force), the vacuum source is the throttle body from those pipes showed in the photo, it's the same pipe conected to the IAC valve, for behind they merge
 

Varun560061

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Good that you have a booster, here in India 800 does not come with a booster, I have fitted one by drilling a hole into the throttle body for tapping the vacuum.

Whats the cost of those cords ? I guess you have HID's too.

Please post some pic's of the dash and the rear.
 
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