Misfiring??

[Clgale88]

Had a tapping noise on my engine everyone said was the camshaft pulley but it turned out to be a loose sparkplug. So I took the inlet off tightened the plug pit it all back together and it's misfiring. So I took it apart again cleaned all the plug 1 at a time and put back together and it started fine but now misfires at low revs and when you pull away anyone know what could be it ran better with a loose spark plug?

 

[MicKPM]

Coil Pack, plug lead or possibly an injector fault... the F4R's have very weak injectors and break easily.

 

[muzza]

a had the same problem m8 and went for new ht leads and it sorted it!tryal and error cheapest part first bud

 

[Clgale88]

But all I did was tighten a spark plug as it was loose.

 

[MicKPM]

Are you sure it wasn't misfiring before? Was the plug damaged in any way and did you check the air gap before refitting? Did you get heavy handed with the plug leads when removing them? Are you sure you've got the leads on in the correct order?

HT Leads are, believe it or not, a consumable item that won't last forever - Can't say why its only started since you've put the plug back in tightly i'm afraid or offer any other professional comments on the root cause of your missfire without seeing the car. It is safe to say though that if it 100% wasn't there before its due to something you've done so recheck everything is on properly.

 

[Clgale88]

yea it was fone before i started just the ticking from where the plug was loose. so all id di was tighten the plug not to tight just knipped it up then put the plug lead back on and refitted and then it was really misfiring. mate who works as a audi technician said change the plugs 1st then the leads. also iv had the inlet manifold of 3 times to paint it and then fit new gaskets etc and has alrwady been fine after when i refit it the saem but for some reason since i tightened that plug its now misfiring hmm

 

[Clgale88]

Anyone else know. dad dosnt think it is the plugs as they all look fairly good and new and are NGK racing ones in there.

 

[ripp]

I didn't wanted to open yet another topic as I have a similar problem:
the car missfires and starts badly ONLY whel alot of moisture outside (fog, rain-generally late autumn and early spring months)
every time the cure was to take off the leads from the coil pack and wipe them off, then reconnect. sometimes it worked quick other times a bit harder. My guess is moisture enters where the leads connect to the coil pack
So am I right saying that I need to change the leads? or...
ps: plugs are the original ones (NGK) and they are only about 12k old

 

[Clgale88]

I still have this problem only accures when the car is hot its fine when its cold. i dont really fancy spending money on items then its not that. its now started running lumpy on tickover and only misfires at 2k revs after that and before that its fine. so anyone know what i should do.

 

[MicKPM]

Diagnostics for the win

If it was fine before, bar the loose plug, then it must be something you've done and without seeing the car I cannot offer any genuine help or support... if its not obvious to you it needs a garage to look it over and tell you what is wrong i'm afraid.