Think I know but don't know y

[moses]

Alright got this freshly built s13 sr. Puttin some miles in for break in but keep running into problems. Current problem is keep burning up spark plugs ghost white.
First. Started backfiring on deceleration. Pulled plugs found leaky injector, replaced o-ring with spark plugs.
Second. Drive to friends house then to autozone to buy a timing light then home. Set timing which was way off (not even on the marks). Fixed, drive to friends and back, backfire again. Pull plugs and there all white as hell.
Third. Switch them out cause maybe it happened with bad timing. Drive a couple mile circle and pull plugs again because of backfire. White as hell.

Now my air fuel ratio gauge is reading lean then rich. Bounces all drive. Fuel pressure is at 43psi at idle. Tune and timing is good. My guess is fuel pump, but it doesn't explain backfire because backfire is unburned fuel. I'll change fuel filter too just because too (it has 300miles on it). I never hit more than 2lbs of boost which was on accident so nothing should be hurt. Im using NGK bkr7e spark plugs. Could that be it since I'm not getting into boost? What do you guys think?

[landins13]

white plugs are from getting hot are you using a wideband or a narrow band a/f gauge cuz if its a narrowband all they do is act like strobe lights. sounds like an issue with the tune

[moses]

I have a wideband, I think it's fluctuating because the fuel delivery is not on point. The tune is a jwt mail ecu that worked great before the motor build. Does anyone have any other idea of what it could be? I'm starting to think it was the reason I melted that #1 piston. Fuel couldn't get to that nozzle fast enough.

[slider2828]

Go get your injectors checked its cheap, any shop can do it or you can do it yourself, Also is the whiteness on all 4 plugs? Also change your plugs to 8's and see if that helps.... when you run the motor, hopefully you don't hear any knocking?

Also the fuel pressure should be 43psi at idle with the vacuum off and vacuum in should be in upper 38's....

If its on all 4 plugs, Maybe its voltage to fuel pump or the fuel pump itself.

[moses]

Damn I forgot to take off the vacuum source but I don't think that is it. I did get all my injectors tested and cleaned while I was building the motor by a good injector place. Yes all 4 spark plugs are white. I have not boosted yet so I better not hear knocking. I did not even think about the voltage to the pump. Thanks a lot. How do you check that?

[moses]

My computer crashed and all I have is my iPhone so I can't look at the FSM. Can someone tell me which color wire is suppose get the 12 volts from the battery?

[moses]

Someone please shed some light on this. I just got done installing a fuel filter, fuel pump, and hardwired it but my plugs are still turning white. It does run better tho. I don't know why but I started to think about it and I use bkr7e spark plugs when I drive normal, but I am not driving nomal. I don't get into boost. Could that be why I am going thru spark plugs? Slider2828 said I should use 8's. Would that help me since I am not boosting right now or do I go the other way? Or do you guys think I have another problem? Thank you slider2828 for all your help. This is what it looks like after driving about 15 miles freeway and street.

[HemiCharger]

Originally Posted by moses

Someone please shed some light on this. I just got done installing a fuel filter, fuel pump, and hardwired it but my plugs are still turning white. It does run better tho. I don't know why but I started to think about it and I use bkr7e spark plugs when I drive normal, but I am not driving nomal. I don't get into boost. Could that be why I am going thru spark plugs? Slider2828 said I should use 8's. Would that help me since I am not boosting right now or do I go the other way? Or do you guys think I have another problem? Thank you slider2828 for all your help. This is what it looks like after driving about 15 miles freeway and street.

you know that I have an Audi 2 liter turbo car and my sr20det turbo 240 and all the plugs look similar to what you are showing on both cars? I think that the turbo cars lean out when decel and will show like that. I have had no really any other trouble other than the plugs look white like that and my audi is all stock. Turbo cars run high cylinder temps. As far as the back firing? are you run a recirc BOV or is your BOV to the atmosphere cause you will get a little back fire on that should no be bad or very audible but like little burbs.

[moses]

Maybe I am being to paranoid. I just don't want to toast another piston like I did last time. I got a lot of money in this thing. Anybody else?

[Def]

Plugs are a little white, but the soot/brown area around the bottom of the threads leads me to believe the AFRs aren't that far off. The electrode should be a very light tan color when everything is running well.

What's your wideband read at idle, cruising(say 40 mph in 4th, constant throttle), and building up to about 0 psi. Should be around 13-15:1, 14.5-15.3:1 and about 13-13.5:1 respectively.

[moses]

At idle and crusing at the same rpm it is normally around the 14 range. It is really hard not to spool up the turbo but when I do on accident it drops down to low 13's. I think I am going to try to drive around a little bit more and see what they look like after that. I just want to hit 500 miles so I can see how it acts under boost in normal conditions. I'm at 370 miles.

[slider2828]

Its completely normal.. The plugs are too hot though.... The white should stop at the curve of the grounding strap (your white thing).... So if you get 1 more step up, bk8res, the white will stop in the right place. Lean or rich is to read by looking at the top ring landing. Black extending all the way down to the 1st thread, is just a tad rich... But safe...

Also! You look just a tad lean though.... but that might be because you cruising at low rpm cause those rings look brown... But could be from your camera...

Put in plugs run around for like 15 an check the plugs for best accuracy.

[moses]

Ok for some reason I can't find NGk bkr8e spark plugs in any of these stores around here so I guess I will have to make due with these 7's. I drove around yesterday for about 70 miles and it drove beautiful. Not as much fluctuation in the a/f gauge. I got 90 more miles and I'll see if it changed when I start boosting. My car dies tho if I get off the throttle and straight on the brakes and clutch. I am pretty sure it is a vacuum leak somewhere and I can't for the life of me find it. My gauge is reading 11inhg which is even low for a sr with jwt cams and thick headgasket. I sprayed carb cleaner everywhere I could possible think of.

[HemiCharger]

Originally Posted by moses

Ok for some reason I can't find NGk bkr8e spark plugs in any of these stores around here so I guess I will have to make due with these 7's. I drove around yesterday for about 70 miles and it drove beautiful. Not as much fluctuation in the a/f gauge. I got 90 more miles and I'll see if it changed when I start boosting. My car dies tho if I get off the throttle and straight on the brakes and clutch. I am pretty sure it is a vacuum leak somewhere and I can't for the life of me find it. My gauge is reading 11inhg which is even low for a sr with jwt cams and thick headgasket. I sprayed carb cleaner everywhere I could possible think of.

if your car dies like that it has to be the main booster vac line coming off the brakes. You running aftermarket cams? what is your idle set at?

[moses]

I have jwt S3 cams. What I did was block off the connection the brake booster connect to and it was the same so it couldn't be that. My idle is smooth at 900 so I am starting to think that it is normal to have 11-12 inhg. Anyway I hit 500 miles and changed the oil which was black as hell. I slowly started boosting around town and I am in love again. I plan to drive 1900 miles tomorrow so wish me luck.

[codyace]

Any insight to the issue?

A vacuum reading of 11 ideling is very low...what does it goto at 1200/1300 rpm? Also, is your timing set correctly? That too can cause oddball vacuum issues


Additionally: JWT cams sometimes require a cam idle program in order to work right in some setups.

[rollout240]

are running an open atmosphere BOV? I am and everytime i drive a backfire. once i recirculated the BOV. Backfire went away. just a thought.
good luck.

and i can't recall were you said 11 for vaccum on idle but that my friend is low.

[moses]

I never did figure out what caused the low vacuum. I looked for a leak and could not find one. It drove normal as hell thru out the whole rpm. I lined it up right and put a timing light to it so I had it the best I could. I didn't recirculate the bov because I was going map after I installed the aem ems.

My conclusion is the valve was not installed right and when I hit 15 lbs of boost it just got loose and fell out the next day. And the headgasket thing didn't effect anything. It probably would have blew later. I don't really know.