Can A Semi Stock R33 Run Lean

[WogsRus]

HI all

well just for good measure i wanted to see what my sparkplugs looked like, after i put in new ones, the car had propably done 300 kms sine i put them in. I had some shit fuel last tank too, cos i got only 300 kms out of it, normally 400 or so, but also a heavie foot this time, .

So i took them out, and well they possibly look like beeing lean, the top electrobe was witeish, and the ceramic was wite, which i take to be lean. kinda like this (see pic)

However looking at this site

http://www.dansmc.com/Spark_Plugs/Spark_Plugs_catalog.html

they come in at number 20 GOOD.

The new plugs were NGK BCPR6E ( i think )

Now the old ones were the iredium ones, but they were long past use by date, and they looked perfect like number 15 on the page. They were NGKs the one the website recomends)

The car pulls the same as before, goes the same, does not get hot or anything, idels fine, starts within 2 seconds of cranking, no problems with boost (still running 7 psi)

The only mods to the car is a HKS pod filter and a full exhaust with 3" dump pipe. (i might have possibly an exhaust leak, still not sure, can't find it, but sounds like it in the pipe, do a search for the post)

Is it possible that the car is running lean or something?????????????????

I am goign to reset the computer tonight to make the car relearn the new pipes ect.

ALSO when i back of or at high rpm gear changes, the car backfires, like it was ritch, so i'm confused.

HELLLLLLLLLLLPPPPPPPPPPPPPPPPPPPPPPPPP

blody turbos, this was never this hard on an atmo motor.

EDIT: Plugs running are BKR6EYA gapped at .8mm

Edited August 31, 2006 by WogsRus

[paulr33]

the ecu wont relearn the new pipes, its basically just a map clear and try 2 deg advance. its hardly a complete retune feature if thats what you are thinking. if you suspect its runing lean you should get it on a dyno with a wideband sensor and see whats coming out. the stock ecu's usually run mega rich on WOT so that could explain the backfiring on max load and gearchange.

the only logical explanations i could see for running lean;

remapped ecu

fuel pump failing

lack of fuel pressure or incorrect

clogged or shagged fuel line/filter

[WogsRus]

well the ECU is stock so no go there.

I am going to check my fuel pressure today to see what the pump is doing. Maybe it's on teh way out.

A sto fuel pressure ect, that will be looked at too. The fuel filter is new.

But like is stated in my other post, i tried to fit an adjustable FPR and no good, either the guage is broken or the pump is stuffed, as i could not get more the 40 psi across the reg, but when the car came onto boost it simply ran out of puff.

Anybody else, What are the symptoms of a car running lean?

[WogsRus]

hay guys, had the fuel system tested, and well, humm

at idle 700rpm with vac on 25psi

without 700rpm 30 psi

at 1200 rpm with vac 32 psi

at 1200rpm no vac 35psi

at 6000 rpm at boost max 42 psi

MAX PSI with return off 42 psi

SO my pump is berley running in there.

SO got a walbro high flow last night, replaced the old pump, it was not a direct fit, and I needed an big clamp to secure it to the cradle, but all ok.

The car is much more responsive at low rpm and same at WOT, but the pump noise is great, sounds like a horny beeeee.

LOL

I'll try and fit the reg on and see what happens.

ALSO, has anyone had any trouble with the connection of the old plug to the new plug with the supplied crimp connectors, I crimped mine DAM HARD, and I could not pull them apart by hand. BUT it seams a little dogie, might pull them out and get some shrink wrap.

ALSO, does the pump cradle just suppose to float around in the bottom of the tank, seems a bit strange.

Thanks all

[WogsRus]

hay guys i'm back.

Well i got the new pump on and direct wired it to ensure correct flow.

I tried to connect my new fuel reg, but it seams that if i take the old reg out and connect this one streight up, then the car runs like crap at high rp at 38psi idle fuel pressure but if i crank the fuel pressure down it runs like crap at low rpm but good at high rpm.

BUT if i leave the stock one in and the new reg connected in series, then it works fine.

DID You guys remove your standard reg or connected it in series. The fuel pressure can still be controlled, as teh fuel pressure will be the grater of teh two regs, simple pressure equation, but it seams wrong to do so.

Is it because theer is sooo much more flow over the stock pump ect????????

HELP.

[Abo Bob]

The pump cradle is not supposed to just float around. On my R34 there is a rib on the inside of the tank which the cradle slides on to.

Are you sure you are removing your stock regulator and not one of the dampers? I have 2 dampers and a reg on mine and they look the same to me. Somehow when I tried to fit an adjustable fpr I hooked it up so the flow was backwards and I deleted a damper thus meaning I had two fpr in there. I have no idea how it ran at all but it did... just not very well.

[WogsRus]

well when i picked my pump out, it just came out, it did not sit in any groves, just in the cradel, in the bottom of the tank. Has somone got a picture of where it should sit in the tank and i'll see if i can get it in there properly, it seams fine for now.

Yeah i removed teh righ reg, the r33 has the damper after the reg not before it, so i have no idea what is going on.

STILL LOST

only managing to get 300 to 350 km on 50 liters, DAM IT.

[The Alchemist]

When fitting a new pump, especially, or when servicing your engine every 20,000 km change your fuel filter!!!!! very important, often forgotten and YES they do block up and don't last forever. We've seen a few lately thru work on "problem cars" no one else can fix etc etc and the damn fuel filter was stuffed.

A trap for young players, too, is that the fuel pressure can "look " ok with the usual inline tests but the flow is whats missing.

Perhaps fitting a new grunty pump only masks what is a simple problem?? ..... mmmmmmm

Hope this helps,

Mike

[WogsRus]

Yeah, i replaced the pump, but also replaced all lines with new high pressure EFI lines and filer ect ect, all good, i tend to go overboard with all my things, i'm a bit anal. The car runs better and id gettign a tune on tusday.

In regards to the pump cradle grouve, i certainly have can't find anything in my tank to secure the pump.