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Hi all.

Just wanna know what limp home mode does to your engine.

I know it limits revs to about 2500 I found that out through searching for answers.

Will it cut cylinders?

3 and 5 aren't firing I have changed coils around changed plugs and tries new ignitor.

Also tested all wiring from ecu to coils and all were good.

Cheers.

Edited by bunno32gtr
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Check with an led test light that the coilpack is getting a signal. Use the led light on the signal wire and the clip end to power and it should pulse the led test light. If it doesnt check the same wire but before the ignitor. If there is still no pulse check the same wire but at the ecu. If there is still no Pulse try another ecu

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there is no limp home mode

there is backup operational modes for sensors that fail, but not a single "limp" mode

ie, if the AFM fails the REV limit is set to 2500rpm

each sensor has its own set of defined backup operational modes

not one mode suits all failures

when did your problem start

what has changed before it started

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Problem started about 5 weeks ago and I have been slowly working it out as I'm a shift worker and had no time. Thought I could be afm's but when I replaced them it was the same. Then checked over all piping and that was good. So I started to play with the coil packs and noticed that I can unplug 3 and 5 with no effect to the engine revs

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its good thats its doing it at idle, makes it much easier to diagnose, pull the spark plugs out and check there condition especially the dud cylinders, might have a crack in the porcelain etc, need to check them and post up some pics, keep them in order but

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have you tried testing your injectors from 3 and 5?

reason is that i had similar problem with no.3 didnt fire had checked my coil pack and igniter and no luck.

i unplugged the connector from the injector and show no difference with the engine revs.

so i took no.3 and switch it with no.1 and no.3 was fine while no.1 played up. turns out injector 3 was the problem

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