Flat Spots

Discussion in '2nd Generation (2001-2008)' started by legend-ary, Tuesday 23rd Feb, 2016.

  1. legend-ary Moderator Staff Team

    United Kingdom Legend The Big Smoke
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    I think i have mentioned it before but while accelerating, there are some flat spots in lower gears. I am thinking of cleaning the throttle body and EGR. I know throttle body can be cleaned with Carb cleaner but EGR.. can I use the same?

    I also have electrical contact cleaner so wondering if that can be used on throttle body as my Jazz has electronic throttle so just wary of damaging that.

    I should add, I once cleaned throttle body of a Yaris with carb cleaner off the car but forgot that I am spraying it infront of headlamps and the headlight plastic just melted/turned fuzzy :Grin: so I understand carb cleaner is very strong but I won't be taking it off and will spray while in place.. is that a bad idea?
    E__0101.
    Update: [incorrect photo deleted]
     

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    Last edited: Wednesday 24th Feb, 2016
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  2. jd1959 Valued Contributor ★ ★ ★ ☆ ☆

    Ireland Zack Kilkenny
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    Not and expert but if the photo is accurate its not an electronic throttle, drive by wire, etc (without cable from pedal to throttle body). If it is an electronic throttle I would think with cleaning the throttle is that you will need to do an idle relearn procedure. Disconnect battery for a while, reconnect, run car to hot (fan on twice) without any electrical load and let it idle for 5-10 min. If your removing it clean it with carb cleaner. Also be very careful of the moving the throttle plate to much or quickly I've heard of people skipping/striping/flattening a gear in the mechanism for throttle plate.

    If it has a cable, clean like any other throttle and put it back together. The EGR is straight forward with carb cleaner and a pick/small screwdriver you can get it reasonably clean.
     
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  3. legend-ary Moderator Staff Team

    United Kingdom Legend The Big Smoke
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    Actually my throttle body is the top one. I accidentally attached the manual one (deleted now).
    So cleaning TB with carb cleaner should be ok and do it the idle learn procedure which sounds easy enough although in such cold weather I doubt the car will turn the fan on.
    But yeah thanks for your reply :Niceone:
     
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  4. jd1959 Valued Contributor ★ ★ ★ ☆ ☆

    Ireland Zack Kilkenny
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    Rev the engine to 3k RPM the fan will turn on eventually even in the cold. Had the battery out on mine for a while when adjusting the valves and had to get it up to temp, it took about 10 min but it was frosty out and in the shade. You will be able to drive without the idle learn but it will be hunting and surging while driving so best of letting the ECU relearn the position.

    Thing I find about our L13a iDsi is that the upper RPM band is very flat and unresponsive, (this is also though a CVT so very hard to tell anyway) but the L15a VTEC (CVT as well) we had in the Mobilio seemed much better in the upper end but lacked pull in the mid-range. A bit of an apples and oranges comparison but my two cents on the engine design.
     
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  5. legend-ary Moderator Staff Team

    United Kingdom Legend The Big Smoke
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    Will give it a go and report back this weekend hopefully.
    You are correct the L13 in GD has bags of low end torque. 3rd Gear 30mph is no issue at all however it looses breath at around 4800rpm. The reason I think these are flat spots is if I floor the car on 1500rpm sometime it is caught off guard .. sometime it accelerates fine but there is a pause and then it continues accelerating.. Clutch although a bit high is fine as I have tried high gears on inclines and no slip at all so I am thinking maybe something sticks. Mind you on cold starts the car sounds like a truck/diesel so I am thinking my valve need adjusting too but I haven't done that before so not touching that.
     
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  6. jd1959 Valued Contributor ★ ★ ★ ☆ ☆

    Ireland Zack Kilkenny
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    It's not too bad of a job for a Saturday afternoon, but the L series engines need the intake removed to access the rocker cover which adds a bit of time and frustration. At least the engine is accessible on the GD, in the StepWGN the engine is under the front scuttle panel and your adjusting the exhaust valves by feel, truly a pain in the donkey. If its an iDsi you only have 8 valves rather than the 16, which probably balances out the time taken to remove the intake.

    Hope the cleaning sorts out the hesitation.
     
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