How can I tell if my car is misfiring? - Saxperience

seals_nav · 20th February 2009, 13:07

I posted here a couple of months ago that my car judders back and forth when driving...this happens randomly, sometimes not at all if I drive and it can happen when I drive later during the day.

Some users here suggested it may be an engine mount, the garages don't seem to notice anything wrong. So is it possible it may be misfiring or something along those lines?

Here are the symptoms of my car:

- Judders back and forth when driving and stationary
- Opening bonnet I can see the rocker cover box vibrates now and again which causes the car to judder
- Opening the gas value under the bonnet...the engine moved towards me then back to its normal position once I put back the gas valve.
- The rev meter works fine.
- When the car is stationary I can feel the car vibrating very slighhtly.
- When driving at high speed the seems to be little or no judder, the car judders more at lower speeds.

Any other things I should check would be helpful, thanks. So is this a misfire, mount or something else?

bigcalturbo · 20th February 2009, 20:24

checked the coil pack and plugs are clean and tight?

-ED- · 20th February 2009, 20:46

If it misfires, you really will notice it. If your driving along in gear, the whole car will shake. When my car miss fired it was becuase the coilpack had water in it.....

seals_nav · 20th February 2009, 22:15

Quote:

Originally Posted by bigcalturbo

checked the coil pack and plugs are clean and tight?

Nope, I have no idea where to find those unfortunately.

GoGs_MacAulay · 20th February 2009, 22:17

Quote:

Originally Posted by -ED-

If it misfires, you really will notice it. If your driving along in gear, the whole car will shake. When my car miss fired it was becuase the coilpack had water in it.....

............

GoGs_MacAulay · 20th February 2009, 22:23

how bad is this judder and where u feeling it from? e.g just the steering wheel?

bigcalturbo · 20th February 2009, 22:27

what car is it? what engine is it?

smithy106 · 20th February 2009, 23:10

shoot it and if you miss your misfiring.....

bit more grown up checked the spark plugs, coil pack??

seals_nav · 21st February 2009, 00:42

Quote:

Originally Posted by GoGs_MacAulay

how bad is this judder and where u feeling it from? e.g just the steering wheel?

No...I can feel it when I sit in my driving seat.

seals_nav · 21st February 2009, 00:42

Quote:

Originally Posted by bigcalturbo

what car is it? what engine is it?

VTR 1.6, 2001 (Y reg)

goodall3518 · 21st February 2009, 01:13

mine does this randomly sometimes too.. usually when i am de-celerating...

good service should fix or what?

RICKYP-RPM · 21st February 2009, 01:31

very difficult to diagnose without seeing the car but from the way you describe the fault it sounds like it could be the engine mount on the drivers side under the ecu. (usually the bolt that goes into it from the bottom snaps).

a diagnostic check should show a misfire up.

bigcalturbo · 21st February 2009, 01:58

you can normally tell on idle if you slowly press the accelerator you can norally tell the change in tone

Roasthunter · 21st February 2009, 07:14

It does sound like a misfire to me. Main culprits are likely to be sparkplugs, HT leads or coil packs.

grahamos1 · 22nd February 2009, 14:46

check the coil pack i had same problem even ticking over the engine shaking well the whole car no power and if you are reving it give the pedal quick bursts u will notice it wont rev properly

maney · 17th December 2009, 20:03

i have the same problem with me 1.4i saxo, iv changed the 4 spark plugs and changed the coil pack for a vtr one and still have the same problem

bit confused on what to do my car sound like a f**kin hellicopter LOL any ideas???

JonCarter · 17th December 2009, 20:56

Check coil pack, HT leads, plug caps if all fails turn to timing! but i highly doubt timing if its still running imo

Saaamon · 17th December 2009, 21:21

Check your plug gaps.

stingray1987 · 17th December 2009, 23:24

sounds like one of the sensors in the t.b to me. give everythign a clean ad replace your sparkplugs just to be sure see if that helps at all.