How do Igniters fail ?

[taylormj4]

As title, do the igniters fail completely or do they give part-failure on the way out.
Reason for asking is I recently have much worse shunting and general not-good running on lighter throttle openings.

Rovergauge doesn't show any fault codes or anything obvious.

Could be a number of things of course but just aware I am still on the original igniter unit and car is now almost 18 years old and done 65,000 miles.

Still on original injectors too I believe.

Before anyone says, no it's not the stepper playing up as I've cleaned it, manually set it to a low idle position and disconnected it from the ECU.

Thanks.

[jojackson4]

Do the coil and amp together
What's it doing on a held throttle Eg2500 rpm ?

[blitzracing]

Its just a semi conductor switch- and to work reliably if has to go from an on to off state very rapidly, but semiconductor can fail by becomming slow to switch or start leaking current, so the on off switching becomes poor. This will make the spark HT drop of significantly, or could lead to overheating of the coil or amp. From a diagnositc point of view you would either put the coil primary on an ignition scope like a crypton tune and check the waveform, or you can buy an HT tester. Ive got one of these it works well, and they are now out of production, so get it while you can- its a bargan!

http://www.ebay.co.uk/itm/Gunson-Peak-KV-Tester-GC...

[taylormj4]

jojackson4 said:

Do the coil and amp together
What's it doing on a held throttle Eg2500 rpm ?

Smoother at higher rpm, when driving, but if stationary and hold a high idle, you can hear what sounds like the odd misfire.

[jojackson4]

Bin them both

[taylormj4]

jojackson4 said:

Bin them both

What are you recommending Jo. An upgrade ?
Matt

[jojackson4]

Replace for good OE parts
Or bin the lot and go aftermarket ECU
OE parts £50
ECU >2k
Have a Google for the part Numbers
Blitz is the guru