CHECK ENGINE LIGHT

[jbjw2001]

My Lexus wants to take off but seems like its being held back - had both knock sensors replaced with the intake manifold but check engine light came back on about 3 hours later - but later it will run like new again and check engine light goes off - then comes back on later with engine problem again - whether its a day or an hour - its weird - any help please - mechanic from lexus dealer said ED1 connector or ECM (engine control module) - I am going to replace Mass Air flow sensor to see if that helps - any suggestions?  Started to get very expensive - BEST CAR I HAVE EVER OWNED - by the way - Please help with suggestions - thank you 

[TrevC]

Would need faults codes to really establish the cause(s) for the lamp coming on

[jmsed]

I just had the same type of issue with our 2001 LS430, i needed to replace the wiring harness for the knock sensors also as there were signs of dry rot and wiring exposed causing additional electrical current draw. Hope that it may help your problem.