Missfire

[ozz]

hi all..just aquired a cheap ls400 as a runabout for a while but its got a missfire around 1.6k to 2.4k rpms

car runs faultlesly other than the missifre.

just cruising at 55 to 65 the car jerks a little back & fourth..fine when accelerating or holding any other speeds..

just drove it for 4 and a half hours solid and apart from this issue its sweet as

do these suffer from any missfire issues around this rev range or could it be just down to a dodgy plug??

[steve2006]

Hello and welcome to the LOC.

A plug misfire would normally be present across the complete rev range but that doesn't necessarily mean it isn't a plug.

It depends on how much you want to spend but I would start with the plugs then the leads.

Another possible cause could be the TPS but that would normally flag a fault code up.

I would pull the plugs and check their condition first.

[ozz]

Hi. Thnks for the reply. Going to service it at the end of the month as ive seen a few things that need replacing.

Car flew through its mot yesterday but only scraped through on the emissions so something to look into there.

Will look at the tps today.

No fualt codes found either so im guessing it mite just be down to needing a service as it has been stood up a while.

Was still a bargain so worth spending some cash onit :)

[ozz]

looks like we sorted the strange misfire..was down to the air filter it had on it.. replaced it with a new hks one and fitted it properly and bingo no more missfire:)