Air Flow Meter Problem

[evannstenny]

Hi everyone,

I was enjoying my luxirious Ls400 for quite a long time b4 disaster struck. It started over heating, cost me some quid but finally it was d water pump and i replaced it. Bingo d over heating stopped. And almost immediately it started jerking wen on motion and wen i stop and put d gear in d Park position then fire d engine, d reving was unstable and d rpm was jumping. I thaught it was d plugs but it wasnt

Here is wat i have done so far...

Change the plugwire

Checked the plugs

Checked the distributor system

Checked the timing system - my mechanic said it wasn't from there

So pls any help would be richly appreciated.

Thanks

[evannstenny]

sorry, forgot to mention - my mechanic said it could be the air flow meter problem. but i'd like 2 get help here

[steve2006]

Welcome to the LOC. You don't say which year your LS is but I would check all the wiring around the front of the engine which may have been disturbed when the water pump was replaced,check the crankshaft position sensor and make sure the wiring is good and not trapped or damaged.

Check all the vacuum hoses for air leaks,also check the lead from the coil pack (at the side of the engine opposite the battery)to the distributor as it may have been damaged if the belt cover has been incorrectly fitted.