OK today decided was the day to replace the spark plugs, HT leads and various other parts like O2 sensor. After fiiting all these parts back on and taking the car for a run it was misfiring like it did before it was maoed last week at srr. Anyway took out the pfr7b spark plugs and regapped them to .6 which again made no difference. After this i put the iridiums back in and they were a mixture of .55 and .6 so i gapped them all to .55 and put them in to test. The car still runs with a misfire between 0 -2000rpm, i dare not drive it any faster... The car has a simtek ECU so can't be MAF related, its p*ssing me off to say the least i have switched the plugs 4 times today...

Any ideas folks?

Coil packs?

99sti 5

 

OK

So i have now refitted the PFR7B's and made sure that they are set at .7mm however i still having the same issue?

Anybody?

 

Theres defo no water in the system is there? I had this when i fitted an induction scoop and didn't seal around it properly and there was water getting into the air intake. I stripped it and was suprised at how much water had got in. Induction kit on the radiator for a few hours and stripping the turbo inlet pipe and MAF and very carefully drying it and the prob was solved.

 

hmm i dont think so, the only thing that i did was clean the system out with carb cleaner through the air intake pipe whilst the induction kit was removed. I'm completely out of ideas, my mate reckons it could be the coil pack as he went through 3 in 11 months on his EVO, problem is, how can you test multimeter?

Where could i check for moisture in the system ?

 

Take the induction kit off and feel up inside the cone to see if its damp, also take off the MAF and rubber turbo inlet pipe and just take a look inside to see if its damp. Just be very careful with the MAF as the wire inside is very fragile and can be easily broken. Its all very easy to take off, just unplug the connector and the undo the jubilee clips.

 

I took the leads of that subaru sold me last week and replaced them with the original leads that were on the car, still genuine subaru ones and now no misfire at all. Actually the longest lead that runs to cylinder 1 had a different marking on it when i compared the two, the new subaru one was something like "5a" and the older subaru one was something like "6a". I nearly ordered a coil pack as well from them today for £172 +vat shabba!!

Shall be asking for my £65 back tomorrow.

i have plug changing down to a T, 15-20 minutes from start to misfire, i mean finish