help with jeep ht signal

Ask any questions relating to the PicoScope hardware or kit contents here.
If you have any questions prior to purchasing the kit post them here.
Post Reply
kmgreg
Newbie
Posts: 0
Joined: Sat Nov 28, 2009 7:19 am

help with jeep ht signal

Post by kmgreg »

i scoped this jeep cherokee today it had a misfire or stumble when throtle applied.can some one tell me what is going on in the burn time line in the capture.i think the coil is faulty.
Attachments
taken with clamp pick up lead on cylinder1 and3
taken with clamp pick up lead on cylinder1 and3

User avatar
Robski
Advanced User
Advanced User
Posts: 598
Joined: Tue Sep 14, 2010 6:36 pm
Location: Yorkshire

Re: help with jeep ht signal

Post by Robski »

Hi

How can you condemn the coil without taking an amps trace ?

What you are seeing could be plugs/leads.The spark line on the brown trace appears to be sloping upwards which could indicate a lean mixture.

Is this a random misfire or cyl specific ?

Take a primary,current ramp & secondary trace from the affected cyl/s with more time on the screen & at idle & snap throttle & possibly post the PSD file,you are also probably better off posting on a car forum.

HTH

Rob.

kmgreg
Newbie
Posts: 0
Joined: Sat Nov 28, 2009 7:19 am

Re: help with jeep ht signal

Post by kmgreg »

thank for your advice robskie i will try a current trace.the plugs and leads are new when you drive the car it has a single cylinder intermitant miss under load.i was condeming the coil on the road test results and did not understand the traces i got when compared to pico examples.thank you for your replie.

Post Reply