Nick_o_Teen

Help, Just fitted new NGK PFR7B plugs today pre set to 0.70 and checked gap just in case they were pre set wrong but were fine, now car runs like a bag of sh*t, back fires and splutters like hell on WOT.
After disturbing the plugs is it possible a coil pack may have gone due to me changing plugs? runs fine off boost. Original plugs fitted were NGK PFR6G set at 0.70, have I set the gap right. Done a search and most people say 0.70. To dark outside now to swap plugs back. Car is a sti ra V2
Any suggestions!

P20SPD

iTrader: (1)

take plugs out and check, if they are ok, re set to 0.6 gap

you can very easily tap the electrode as you insert the plug, thus reducing the gap to nil.

Nick_o_Teen

Had them out twice and none were closed over, so I will set them to 0.6 and not 0.7, tomorow and see what happens
Cheers.

jonny gav

iTrader: (1)

are you sure you have refitted the coilpacks correctly, it is possible to fit the packs and tighten the 12mm bolt up with the pack out of line.

jonny gav

iTrader: (1)

out of interest have you re-connected the maf sensor correctly, also re-check all pipes on maf sensor side for leaks.

john banks

Did you lean against the central electrode when gapping them?

Nick_o_Teen

Coil packs went back on fine both times,electrodes are fine. never went near the maf as I run A HKS racing suction kit so no need to move anything. It fires on all 4 at low revs, but soon as I boot it say past 3500 rpm it runs crap. If the plug gap is to big can the spark blow out as I am running a higher boost?.
Its a pain in the ***, I've only changed the bloody plugs.

Bob Rawle

what boost are you running, sounds as though disturbing the coil packs has woken them up .... or down actually, you are describing classic coil pack degeneration.

bob

Delboy2

Look under the rubber sheath on end of each coilpack where the plug enters and check to see whether the insulation is cracked. Any damage/cracks will result in missfire

Cheers

Nick_o_Teen

Have been running 1.24bar(18psi) for the last 4 months with no problem, tried it at 1.07bar(15.5psi) earlier today but still the same, will put old plugs back in tomorrow and see what happens. Thanks for all your help guys.

dij

I agree with Delboy and Bob Rawle.

Sounds like coil pack(s) are shorting out

Nick_o_Teen

If it is my coil packs, where is the cheapest place to get them from?

jonny gav

iTrader: (1)

subaru! £50 each

StickyMicky

i hate changing the plugs

my sockets were either to long or to short
i went to halfords to get a extension bar and socket the right size to find they had none

then bought a ****e £3.99 sparkplug remover tool, to get home and find i allready had one of them in a box full of broken turbos

managed it with the tool but it was still a PITA

at one point i had my socket on the plug, and i went to pull it out but the socket came off the extension bar due to the rubber insert in the socket being a tight fit, now how are you supposed to get the socket off now??

much swearing helped, along with sum bendy pliers and a few other bits and bobs i knocked up, from then on in the socket was taped to the bar so it couldnt come off LOL

stockcar

jonny think you'll find that Subaru want around £63+VAT each coil....................... we normally charge around £50inc...........!!

could probs sort something for numbers................

alyn - -asperformance.com

Nick_o_Teen

Checked the coil packs under the rubber sheath's and found cracks and bit's falling off 2 of them. so I think that may be the problem. Dam, more money. :-(

Mark A

iTrader: (1)

Swap to the remote bosch model from Oz, much better and a bit cheaper I think.
I can check the model number later.

Mark

Roojai

I have a set of used coil packs in working condition that I would sell quite cheap. PM if interested.

jonny gav

iTrader: (1)

alyn, subaru must have put their prices up, thats what i paid for mine, it was 2 years ago though.

the oz packs are cheap but i know of people that have had problems with spark blow out using them, all be it on highly tuned engines.

Nick_o_Teen

Hi Alyn, spoke to someone at your place today about 10.30am,don't no if it was you or not the guy never said. He told me the coil packs are due in mid week from Japan hopefully, so I will definitely be in touch for a full set of 4. PM me if they come in earlier,cheers
Nick

Pavlo

coilpacks.

as for the tools, I find a snap on 3/8" drive small plug socket, with a short wobble end extension works well as it allows a bit of flex to put the socket on.

Paul

Midlife......

iTrader: (2)

Errrrr..while Bob Rawle and Alyn are here together...........

I'm trying to duplicate Ninybob's setup with a TD05 and an APS FMIC what plugs do you recommend Bob and can you get them for me Alyn !!

Shaun

stockcar

can certainly sort for you...............NGK PFR7B............carry in stock (also do the racing 8's)

alyn - asperformance.com

Midlife......

iTrader: (2)

Alyn

I'll take you up on the offer of some new sparkplugs !! The Motul Oil came next day..top service

Cheers

Shaun

errrrrrrrrr what are racing 8's ??

Bob Rawle

Expensive usually ... lol, stick to PFR 7B's gapped at 0.7mm.

bob

Midlife......

iTrader: (2)

Thanks Bob

Alyn, can you please put aside a "four pack" of PFR 7B's for me......... thanks

Cheers

Shaun

PS... Alyn, can you fit bonnet pins ??

I've got a carbon bonnet from Fulham 71 and it flaps about like John Wayne's saddlebags. I'd hate for Bob to have to map the car with one eye on the laptop and the other on the "flubber" like bonnet. The bonnet came with the pins already and Fulham 71 has kindly provided the bits which screw into the car.

john banks

I have a few sets of 8s to try:

NGK BKR8EIX (Iridium IX)
NGK R7434-8 (Iridium printed on plug)

The first are about six times cheaper and of more conventional design, the Racing plugs look quite like previous Racing 9s I had.

Anyone tried either? My PFR7Q are still going strong at 0.6mm gap.

vulnax999

iTrader: (7)

Anyone wanna tell me what the difference is between PFR7B and PFR7Q plugs is?

Seems same heat rating ..

john banks

Modified insulator to take the punishment better.

Job had some of my worn 7Bs checked by NGK and they said that the insulator and precious metals had degraded because of excessive temperature and pressure. The 7Qs were recommended as an alternative with a modified insulator as an alternative at the time to going to tricky to get hold of or expensive 8s.

The previous 7Bs degraded at similar mileage to what these 7Qs have had so far, so I'd like to continue to see what happens with these. 7Qs are OEM fit on the Audi RS4/6 and have fixed a similar problem. However, since they are dealing with 6 or 8 cylinders and similar power levels to my present with 4 cylinders, I still think they might not be up to the job, but I suppose in the Audi they are expecting them to last between service intervals for spark plugs, whereas I am changing mine far more often.

The 7Bs don't seem to fail catastrophically, they just start a miss that is mild initially then like a fuel cut on high boost.

For up to 350 BHP 7Bs are great. At 400 BHP they can go off a bit quickly - I reckon about 5000 miles, at 450 BHP they last a few thousand miles. Just a guess from memory on power levels and times, I don't write it all down. Of course usage will affect things as well.

jonny gav

iTrader: (1)

i only get 4k out of 7b's before they need a change, its still cheaper to just replace them 3 times than go for a good set of racing 8's

whats the price on the 7Q's john???