Can anyone tell me what cause a flat spot when I slowly push the go pedal on my NH 3 ltr ? It seems to be worst of all before the motor really warms up which causes a non normal auto gear change.
All help appreciated.
Regards Salty.
Notice: We request that you don't just set up a new account at this time if you are a previous user.
If you used to be one of our moderators, please feel free to reach out to Chris via the facebook Outerlimits4x4 group and he will get you set back up with access should he need you.
If you used to be one of our moderators, please feel free to reach out to Chris via the facebook Outerlimits4x4 group and he will get you set back up with access should he need you.
Recovery:If you cannot access your old email address and don't remember your password, please click here to log a change of email address so you can do a password reset.
Accelerator flat spot
Moderator: -Scott-
Dead set. The last few times there has been a problem with my car, i've fixed it, and when i jump on outers of a night time there has been a thread about it. It's bloody spinning me out!
Mine was doing a similar thing (mine is manual tho) where it was almost surging, bogging down mid rev range and was worse when cold and after idling for a while. I advanced the timing a little which helped but it would ping under high load. I thought i would check the TPS (throttle pos. sensor) as the airflow meter is a karmen vortex type which never normally give problems.
Now using a multimeter, the voltage reading between pin 3 and ground should be about 0.8v at idle and 5 volt at WOT. (presuming the voltage reg in the ECU is working and sending out a 5 volt reference). Tested mine today and it was 0.8 at idle but only 3.9v at WOT. So i "advanced" the TPS until it was about 4.7v @ WOT and 1.3v at idle. Bingo!!!! problem solved. I also added a few degrees of timing again and no pinging.
Now to me this would indicate that the potentiometer in the TPS was slightly out and not giving the ECU the full 1-5v adjustment that it needs. The luxury i have tho is mine is manual and it doesn't need to be spot on for the Auto shifting. (and i'm a tight arse)
I would start by checking the voltages at the TPS and adjusting the switch with a bit of trial and error. If the engine revs smoother but the auto shift is still dodgy then it may need replacing. Its somewhere to start anyway. Good luck
Mine was doing a similar thing (mine is manual tho) where it was almost surging, bogging down mid rev range and was worse when cold and after idling for a while. I advanced the timing a little which helped but it would ping under high load. I thought i would check the TPS (throttle pos. sensor) as the airflow meter is a karmen vortex type which never normally give problems.
Now using a multimeter, the voltage reading between pin 3 and ground should be about 0.8v at idle and 5 volt at WOT. (presuming the voltage reg in the ECU is working and sending out a 5 volt reference). Tested mine today and it was 0.8 at idle but only 3.9v at WOT. So i "advanced" the TPS until it was about 4.7v @ WOT and 1.3v at idle. Bingo!!!! problem solved. I also added a few degrees of timing again and no pinging.
Now to me this would indicate that the potentiometer in the TPS was slightly out and not giving the ECU the full 1-5v adjustment that it needs. The luxury i have tho is mine is manual and it doesn't need to be spot on for the Auto shifting. (and i'm a tight arse)
I would start by checking the voltages at the TPS and adjusting the switch with a bit of trial and error. If the engine revs smoother but the auto shift is still dodgy then it may need replacing. Its somewhere to start anyway. Good luck
Who is online
Users browsing this forum: No registered users and 0 guests