Bought a s15 today but...

[craig8585]

You won't need the injectors, the standard ones will be ok at that level but bigger ones wouldnt be a bad thing.

A simple RR session just to get yourself some graphs will cost you £40-60. A remap session on a RR (what you'll need to safely crank the boost up) costs a lot more.

 

[Toby]

Its got Tesco value in it atm.

I am picking up some octane booster on the way home tonight and will pop some in to hopefully raise the 1/4 a tank I have left to something closer to the 99mark.

 

[tooley]

Thats explains that then,

100% detonation is your problem. lucky it has not melted a piston. Dont rev it high or put it under alot of load with **** fuel in.

Bad fuel

I use shell or tesco 99 ron.

 

[Toby]

Car is going in for its MOT tommorrow, I will ensure the remaing 15ltrs in the tank is mixed up with some 99 ron and octane booster, and will see what occurs on the way to the garage.

Just bought some NGK BKR7EIX's too!

 

[tooley]

sweet man hope you get it sorted.

 

[Toby]

Here's the plugs that came out...

 

[craig8585]

I've never seen plugs looking quite like that before! If that was caused by det then your lucky something else a lot more important didn't melt too!

 

[Toby]

Eeek!

well i can't do much now other than drive it on super unleaded and keep an eye on the plugs..

 

[Amused_15]

i got this problem when i first got my s15 too...but nothing regarding white smoke...here we have ambient temps of 35-40 degrees C....you could try checking your timing too....when i got mine from japan it was advanced way too much...my mech recorded almost 25 degrees btdc....i pulled mine back to 15, adjusted the idle screw and now she only pops occasionally....grade 8 platinum plugs will definitely help...and then RR the old gal to check the a/f ratios. Hope this helps as well....

i understand that in Japan they are 'generous' with the ignition timing cos of the quality of fuel they enjoy over there....i think in the UK you guys only have optimax and BP's ultimate right? In malaysia we mostly run 97 octane. Its the highest grade pump fuel we have.

 

[Toby]

There is 99ron widley available out here.

 

[tooley]

Here's the plugs that came out...

Can you see the way the node has a melted edge on it?? ( the 3rd from left) Definatly detonation as its been melted off! lucky you havent done any piston damage!!

Least the car is running ok now???

i change my plugs evey 15000, not sure about anyone else, ?

 

[Toby]

The car is not running right though, it missfires 500rpm before the redline?

I wouldlike to say its becuase the fuel pump needs upgrading, or the spark plugs need to be changed to some grade 7's, but the car is only running .5 bar....

 

[Toby]

Me again!!

I noticed my turbo timer does have a the A/F O2 Voltage and it reads between 0.23 and 0.33 when driving/idleing - does this mean anything good/bad?

Edit: good o'l google.

The output voltage levels are calibrated according to the comparative oxygen levels. There are two extreme voltages that indicate two extreme ratios of air and fuel content. If the output voltage of the electrodes is 0.2 V, that indicates the air-fuel ratio is just enough so that all carbon monoxide gets oxidized and carbon dioxide is released. This state is low on unburned fuel and rich in oxygen. As opposed to this, the other extreme is reached at 0.8 V which is an oxygen deprived, unburned fuel-rich state. The optimum engine performance state is indicated when the sensor output voltage is 0.45 V. This is the state where the oxygen content and fuel is in equilibrium and the pollution caused through exhaust gases is lowest.


Seems like the car is as expected running lean.

Glad I ordered that walbro last night then

 

[meddler]

I wouldn't be reving it to redline until it was looked at. The last thing you want is to destroy the engine from it running too lean.

 

[Toby]

I'm not even using the car atm.

I will fit the fuel pump, grade 7 plugs and then see...

 

[LuPix_S15]

Without sounding like a damp squib on a gloomy day, I'd recommend getting everything checked out before you spend money on the next set of mods. First off how much power/torque can you confirm it's running before you you add your mods and then get those readings? Unless it's already been dyno'd recently you'll have no proof how much your mods are going to increase performance etc

Also being cautious is a good thing... for the sake of £60 or thereabouts, it's worth getting the fuel pump fitted and new colder plugs sorted and then having a run on dyno to ensure everything is in order. If you spend all the money now to buy all the bits and then find out on the dyno that they can't even map it beyond stock cos there's problems with running of the car then you can argue that's money which would have gone towards making sure she's running sweet in the first place :wack:


It just seems she's been running too long on some sort of 'hope and pray' crazy setup and V-Power or Tesco 99 should be the ONLY fuel you ever use!! :thumbs:

 

[Toby]

You seem to speak words of wisdom, one point to make is I live on the Isle of wight and there are no trusted Dyno's down here, so its not quite as easy as it is for some.

The compression test shows 1 cylinder is ~10psi down from the others, Once i have actually regestered the car and run some 99ron through her I will have a better idea on whats damaged - the smoke symptons do seem to have gone now since changing the plugs.

If that doesn't resolve things I will have to take the car to Horsham, get it RR'd to see whats what....

 

[tooley]

Like i said it was det and no walbro. glad you have an answer.

You cylinder is down on PSI because its probibly damaged by the spark plug breaking up. If if not down by much i wouldnt worry about it.

Let us know when you have fitted the bits

 

[richy200]

The car still pops and bangs, would it do this is it was running that lean?

Boost is also only .5bar so from what I've read a fuel pump would be reccomended, but not essential? - I will have a look tonight and see before I buy one.

The Plugs were NKG's I'm not sure on the heat range, will check.

The miss fire is like a coil pack is out, yes its upsetting the boost, but the boost is certainly not causing the missfire.

Before I fitted the plugs, it was doing ti as early as 4000rpm, now it does it at 7.

Thanks again everyone

You said the first to plugs, half of them were missing?? i'd be more worried about this, where are the bits that are missing?? if they're in the rattling around mate that can't be good, they're a bit bit to have just burnt up. If your getting a miss fire it could be running lean. As suggested do you have a Uprated fuel pump? check the fuel filter for ****, check afm and clean it remove coilpacks again and take the rubber bit off the bottom and check the springs.

Check for boost leaks

 

[craig8585]

Did you buy the car from a private seller or a trader Toby?