Bogging down at Low revs when driving

[dj-rix]

Just fitted a newly rebuilt engine, on idle it's fine, when driving the car its bogging down at low revs and feels likes its holding back, once it reaches 3k it's smooth and boosts normally, did a compression test and it's equal across all cylinders. What should I check???

[Patches]

I had the same issue a while ago. It could be your lambda sensor/wiring, mine was gubbed and was giving off a solid 0v instead of moving about from 0.1-0.9v so the car didn't fuel properly. When I unplugged the lamba sensor the car drove fine so I knew that was the problem.

Unplug the lambda sensor and see how it drives, when no lambda sensor is plugged in it over fuels slightly so wont be very good for economy but will let you know if that's where your issue lies.

[dj-rix]

Tried unplugging the lambda, it didn't affect it.

With foot flat down it feels like the cars holding back, feels like it's in 5th gear when it's actually in 1st, turbo spools really slowly and takes a while to get to 3k, when it gets to 3k it's fine and boosts fine.

[neilsmith]

Sounds like the throttle position sensor might need calibrated

Or the timing could be out mate

Neil

[dj-rix]

Timing is bang on 10deg at 750 rpm in diagnostic mode

Is there a way to test the TPS?

[H_D]

http://www.toyotagtturbo.com/forums/showthread.php?95258-4-pin-TPS-Check-amp-Adjust

http://www.toyotagtturbo.com/forums/showthread.php?100946-Tutorial-TPS-setup-Procedure-weeJohn-*

[GP82]

You ran diagnostics?!

[dj-rix]

Wouldn't the engine light be on if there was a fault?

[GP82]

Yes it would, but not always. I have seen that sometimes whilst driving it could pop up and go away then when you do the diagnostics the fault code will be stored in the ecu. Have you checked all you ignition components: spark plugs, leads inc. king lead, dizzy cap, rotor arm, coil pack. Also check your cam belt timing and ignition timing.

Edited February 18, 2016 by GP82

[funny onion]

Sounds like fueling issue. ie running lean. do you have a wideband gauge?

[dj-rix]

Plug look white so clearly running lean, there is a big hole in the flexi, would this cause it to run lean?

[gorganl2000]

do a diagnostic and check your map sensor/connections

[dj-rix]

Diagnostics didn't show anything