random missfire?

[MentaLEP91]

Hello folks

2-3 days ago, I was getting my glanza out for a spin, I warmed it up, then I booted 2nd gear and when the boost reached about 0.6 at 3500rpm, the car started to judder and missfire (something like the fuel cut but it was for 4-5bangs, not that hard tho) the engine light didn't go on.
Instantly I let the throttle off and drove it like in 2000rpm.

A day after we changed the map sensor and the fuel pump (oem one) and it disappeared for like 1 day. The funny thing is that it doesn't do this everytime i boot it, its like totally random. Any ideas??

I have no electronic mods on the car

Thnx in advance mates. repp will be added

 

[Mike_ep91]

check your plugs mate common problem on ep's when moisture gets in around plugs due to vent in bonnet.this will cause a judder or misfire as the spark becomes weak.

 

[MentaLEP91]

well i got TRD leads and they are spot on...so I aint think thats the problem.

thnx tho mate

 

[dan_ep82]

dont really matter what brand your leads are water can still get down inside.

check things like plug gapping, rotor arm and dizzy cap. also i know you say your leads are fine but just check for anybreaks in the insulation, have a look in the dark for any arching/sparking from the leads

 

[GTnomez]

can the shortage of fuel cause misfire?

mine started misfiring mad from cold start! real bad, so bad that from cold, as soon as i drive it conks out. today i cleaned out the dizzy cap, the rotor arm, my trd leads, king lead, the ICV and its better but still there is a bit of missing. problem was i cleaned the car straight after i cleaned the ignition so i think i might have to dry the engine out on idle.

 

[Mike_ep91]

well i got TRD leads and they are spot on...so I aint think thats the problem.

thnx tho mate

yeah your leads can be fine but moisture can get into places you think it cant.

dont really matter what brand your leads are water can still get down inside.

check things like plug gapping, rotor arm and dizzy cap. also i know you say your leads are fine but just check for anybreaks in the insulation, have a look in the dark for any arching/sparking from the leads

do all the above and it mite solve your problem.

somethin as small as a break in the cable will cause you trouble.

 

[Streetech]

Mine has been doing the same.
Changed the dizzy and rotor as they looked abit worn and its still doing it. Checked everything else apart from the plugs so going to do that tomorrow, fingers crossed it will be sorted for the track day.

 

[finch53]

check plugs, mine was doing it most of the time between 2000 to 4000 rpm, changed my plugs, quick spray of wd and bobs your uncle, fannys your aunt. tested mine against my mates, before changing plugs his pulled away, just tried now and theyre exactly the same, so good stuff.