1zz not running 100%

[AZA51]

hi everyone,

so for the last few days my 1zz hasnt been running properly, its hard to describe but when im slowly accelerating in low revs the car seems to judder almost like its surging in small short bursts,also spitting and back firing quite alot,its also worst under load..this dosent happen if my foot is flat to the floor thou, ive cleaned my maf sensor and changed the plugs but that doesnt appear to help the situation, ive also had my autolec check it out but he says that all the ignition and fuel delivery seem to be working properly.atm im waiting for my pfc data logit box so i can record wats going on but im not sure it has anything to do with tuning as this is the first time its happened, am i looking at a mechanical problem??

any ideas at all would be muchly appreciated.

[eviltwin]

What you describe to me sounds like the leads need replacing but if an auto elec has tested that it may be fuel related.. when you say tuning , is the engine modified significantly?

[SuperDave]

pfc data logit box

Try turning off O2 sensor feedback and see if that fixes it, could be a dying sensor. If it is already off, then I'm not sure at the moment.

[CHA54]

put the stock ECU back in, then check if it does the same thing.

[AZA51]

What you describe to me sounds like the leads need replacing but if an auto elec has tested that it may be fuel related.. when you say tuning , is the engine modified significantly?

wouldnt say significantly just basic bolt ons.

ill try all of the about to see how it goes ,thanks everyone

[seeka02]

I have the EXACT same problem

But mine happens very little (i.e. not everytime i drive it)

My car has no mods, dead stocker

I will need to try the plugs first

Do these motors use leads? someone told me they use 4 coilpacks instead?

Edited November 9, 2010 by seeka02

[SuperDave]

Do these have motors leads? someone told me they use 4 coils instead?

Coilpacks