1. Introducing the smashing new Team FIAT T-Shirt !! To order yours click here : Team FIAT T-Shirt

GP- weird problem :-(

Discussion in 'Engine Compartment' started by abhinav7373, Dec 4, 2012.

  1. vivekrj.dieselhead

    vivekrj.dieselhead Regolare

    Messages:
    294
    delhi
    BTW many of us get it repaired at sec 63 no problem so far except the body work.
  2. nitinkumardba

    nitinkumardba Superiore

    I am not sure about others but my Punto was with them for around 40 days fot rust treatment, they spoiled my car from top to bottom. Only me and Mr. OP Sharma know how bad they spoiled my car. I don't want to land in old bad memories any more... so no more words on this.
  3. guys i have done hell lot of research on internet and found many reasons behind this. And many cars of different make have experienced this sort of issue. Following points I have note down which I am gonna ask the mechanic to do:
    1. Check for vacuum leak in the car.
    2. Dirty Throttle Body
    3. Throttle Position Sensor (TPS) cleaning and check
    4. Idle Air Control (IAC) valve cleaning / replace
    5. Weak alternator or Loose alternator belt (Check tension of the belt).
    6. Bad Crank Position Sensor.
    7. Cleaning required for MAF and MAP sensor.
    8. Clutch Release bearing (although chances of this are very low as RPM dips even if i release the clutch paddle before 1500 rpm)
    9. to check Battery ground if it is attached securely with battery and chassis.

    :uh the list is too long.. What experts here suggest me to proceed further with the points i mentioned and in which order.??

    I am uploading the link to a video i shot while driving on a less crowded road. The video is lil shaky as i was driving and shooting too :roll: ......... In the video you will see the car stalling two times and rpm dip problem many times. This problem occur more frequently when headlights are on than when they are off.

  4. gurjinder

    gurjinder Staff Member Janitor

    Messages:
    3,989
    Punjab
    I think the only real way to rule out the CNG kit will be to remove it entirely from the car and then take a drive.

    Having said that, the first plan of action should be getting the ECU examined for probable fault codes. That will make the diagnosis and correction much easier.

    Don't show it to any ABC mechanic who will increase the work rather than reducing it. Get that ECU examined firstly at the dealership.
  5. Gurjinder pra ji Last Saturday only i had got the diagnosis done and 2 errors were removed without any problem. But still problem persist. I think it could be vacuum leak because rpm fluctuation is still there when car is running on petrol. I will get it checked on ASC only. But I dont think the problem is with CNG kit. I cant remember exactly but the problem started when I got Timing Advance Processor (TAP) installed (after 2 weeks of sng installation to enhance the performance). TAP is connected with TPS and Crank Position Sensor of the car which might be causing some interference but again when car is on petrol TAP doesnt work then why on petrol rpm dip is there?? God, its is so confusing. :oops: .......
    Last edited: Dec 11, 2012
  6. gurjinder

    gurjinder Staff Member Janitor

    Messages:
    3,989
    Punjab
    There you have it. Not confusing at all.

    Your TAP installer screwed up the install, thereby affecting both the TPS and the CPS. Even if TAP doesn't work when car is on petrol, the installer must've screwed up something so that the functioning of either the TPS or the CPS is affected irrespective of the fuel being used.

    Also, if the car started showing these symptoms only after TAP install, you should've asked the installer to rectify it as it's purely his mistake.
    1 person likes this.
  7. 9
    In the following order I am gonna proceed further:

    1. Will get the TAP completely removed from the car and then will take test drive on both petrol and gas (if it wont work)
    2. Will get all hoses clean (Rubber seal which seals air filter and throttle body), vacuum hoses check will take car to test drive on both the fuels (if this also would not work step 3).
    3. will check and clean the throttle body and IAC Valve (At FASC only) and will test drive on both fuels (If this also wouldnt work step 4).
    4. Will get the Serious Checks for Vacuum leaks at various places like Air intake manifold gasket, around injector seal, Around gas injector seals, once again vacuum hoses check then will take it on test drive (even now if it wont get fine then step 5).
    5. Will get alternator checked and the tension of alternator belt.'
    6. will get CPS changed with a new one

    phew!! i am sure problem will be solved by 1st or 2nd step. Gurjinder would you like to add some other point which i should keep in mind to be checked??
  8. gurjinder

    gurjinder Staff Member Janitor

    Messages:
    3,989
    Punjab
    Yep, get this TAP thing removed and see how it drives. If the symptoms persist, the TPS and/or CPS will need to be checked. Most probably the TPS.
  9. UPDATE:

    The problem seems to be much much much more serious than expected. Got a thorough scan of car done at oberoi motors sector-1, Noida. I personally didn't like Him motors, patparganj. The mechanics dont listen to you carefully and try to convince you about the problem that its natural :punch . Well coming back to the point, I went to Oberoi motors on saturday (29th dec) they put examiner in the car and following error codes appeared DSC_0139.jpg

    But as per the advisor it is not a problem as the errors are "intermittent" and not "present" kind of errors. they removed the error and the errors didn't appear again. They tried replacing the spark plugs and cleaned the throttle body but all in vain. Service guys asked me to kindly get the cng connections removed from the wiring after that only they will be able to further diagnose the problem. I went to cng installer on sunday and got all the connections removed and yesterday (monday) again went to Oberoi cars. Work started 10'o clock and the tried replacing the ignition coil and plug leads but no improvement. Then they replaced the injectors wiring again no improvement. Again they put examiner no codes appeared, they did some resetting of CKP sensor, Throttle body etc etc using examiner but no improvement. They cleaned all the sensors and couplers using electrical cleaner but no improvement. They tried replacing Lambda sensor and Crankshaft position sensor as per my request but unfortunately no improvement at all :confused. They dont know what thing is at fault as examiner is not showing any fault codes. Now they have doubt on two components 1. Engine wiring, 2. Throttle body. Both the parts were not available as in not other car it was required to be replaced ever.
    Last edited: Jan 1, 2013
  10. karan desai

    karan desai Superiore

    Messages:
    805
    Morbi, Gujrat
    my car after cng installation shows similar symptoms. when i press the clutch at a spedd the rpm needle drops to 500 and then jumps back to normal. and when the ac is on and you put the gear in neutral with the car rolling the rpm needle jumps from 500 to 1500 and the cycle continues. this happens only when the ac is on. otherwise the rpm needle behaves well.

Share This Page