Can wrong plugs in a turbo cause this?...

[Burger]

My 92' has Its BKR6EY A's in it instead of 6EP's, just the other day it started to get lumpy/missing when cold, and now wont boost right, infact its stuttery when in boost. I read that to check/replace ht's and/or dizzy (well for starters), they have been done and look quite new. But the plugs I took out are for n/a (6EY A's).

Thing that gets me though, its been fine for a while then just starts this in the last couple of days. I would though if the plugs being the wrong type, it would been like this from word go....or I am wrong!

[Munnsy]

think it may also be to do with the gapping of the plug mate, not sure what toyota recomend

[Burger]

Ok, will check that too...but....(and this might sound daft),

Could Tesco's 99 fuel be causing it, as I have only been using the last few days too. Or is just sheer coincidence that its the wrong plugs starting to not be able to cope with a turbo.

[Munnsy]

shouldnt be a prob, as long as you are always using super, its all pretty much the same stuff mate

[Burger]

I know you say check the gaps (and I will, its meant to be .08-1mm) but should I put BKR6EP's in.

[Greddy-Matt]

Just use copper BKR6E plugs, they work spot on unless you're running more than 50bhp over stock, then change to one grade cooler.. £12 a set from most Motorfactors.

The dizzy cap's and rotors get chewed through quite quick on tubbies and better to go on the last time they were replaced. You do get white oxidisation on the rotor after a while, I change dizzy caps and rotor about once a year, HT leads should last several years tho, just check for rust and oxidisation on the contacts. Eliminate those by borrowing a known good set and trying them.

Oh and sometimes the HT leads don'f fit perfectly snug so make sure there is no moisture/water in the spark plugs well or it won't run right.

[Burger]

Its standard apart from an mbc, so maybe about 20-40 extra, would the copper one's still ok.

Checked the gaps ect and are all fine, as are the leads, dizzy ect are they all quite new with no oxidising ect.

Its really when its cold, its as stuttery as hell till its warmed, then its fine at low revs (eg town driving) fine. But stuttery when going into boost, and instead of boosting about 13-14psi (as it was), its lucky to get to about 12.

[Olly.Dent]

There was a Mr2 Turbo at Surrey Rolling Road with N/A plugs and that misfired all over the place till the plugs were changed so i would say thats your problem mate.

[Burger]

Olly I know what you mean, as I have had that before too..

But its been going great till a couple of days ago, unless...the plugs that are in (BKR6EY's) were ok for a few weeks or a just over a month, but now are maybe "breaking down" due to the extra power and heat of the turbo and NOT being the "6EP's" that are supposed to be in.

Just my guesing..