Why so lean????

CanadianTSi · 10-11-2002, 11:09 AM

Well I just installed my Pocketlogger on my 92 TSi FWD, the car has the following mods: K&N with no air can, Silencer and lower honeycomb are gone,3 inch MAS to Turbo intake pipe,MBC set at 14 Psi, 2.5" Catback and the car always runs on 93 or higher octane.

Looking at my fuel trims the car seems to be running way lean for some reason. My Low fuel trim is at 139% my mid is at 122% and my high is at 112%

Also at the top of 3rd I am seeing some really Low O2 voltages...Like 0.88 and sometimes 0.86. Now I'm guessing that it's these low O2's that are causing me to see high knock counts and bad timing.

So I guess my question is, What is causing me to run so lean on only 14 pounds of boost????

BatmanGSX · 10-11-2002, 11:51 AM

Why are you convinced .88 and .86 are so lean? Does the stupid pocketlogger have knock count monitoring abilities? Check the knock count.

Why are so many people looking at worthless things like 02 voltages and EGTs? It's actually starting to piss me off. TELL US THE KNOCK SUM!!!

jdmawd · 10-11-2002, 01:59 PM

Quote:

Originally posted by CanadianTSi
Well I just installed my Pocketlogger on my 92 TSi FWD, the car has the following mods: K&N with no air can, Silencer and lower honeycomb are gone,3 inch MAS to Turbo intake pipe,MBC set at 14 Psi, 2.5" Catback and the car always runs on 93 or higher octane.

Looking at my fuel trims the car seems to be running way lean for some reason. My Low fuel trim is at 139% my mid is at 122% and my high is at 112%

Also at the top of 3rd I am seeing some really Low O2 voltages...Like 0.88 and sometimes 0.86. Now I'm guessing that it's these low O2's that are causing me to see high knock counts and bad timing.

So I guess my question is, What is causing me to run so lean on only 14 pounds of boost????

if the o2 ground wire on the down pipe is gone it will make the o2 voltage read low like you posted. the answer to every question is not look at you're knock count

hope that helps, my car is pig rich at 0.88v

BatmanGSX · 10-11-2002, 02:28 PM

Quote:

Originally posted by jdmawd
if the o2 ground wire on the down pipe is gone it will make the o2 voltage read low like you posted.

That's true. My car was always pegged at .88. Then I connected that wire that had been hanging down for two years.

CanadianTSi · 10-11-2002, 05:55 PM

I guess I was convinced I was running lean because my knock count was so high...but i guess I forgot to post those numbers....sorry fellas

My knock count is fine up until 5k rpms when my O2 drops to .88 my knock jumps from 0 to 7 and then is at 20 counts by 6000 then it stays around 20ish until I shift. My timing slowly drops as the knock rises and by the top of 3rd is at 12deg

NJGSX96 · 10-11-2002, 10:12 PM

Is it me or do almost all the 92 Talons run leaner than most? Anytime I hear people running out of fuel, it is on a 92. I mean, I was maxxing my 550 injectors out on a 16G and now with the 20G I am close to maxxing my 650s out. Car ran leaner than anything from day one. Only at WOT though. Around town, I have my fuel trims all nice. At WOT, it sucks the gas right up and asks for more.

Canadian TSI, put the lower HC back in. Pulling those makes your car run leaner. Also, rewire your fuel pump and/or drop an upgraded fuel pump in there. Might help some. I've seen older pumps taxed on 14-15psi on 1Gs before.

jw · 10-11-2002, 10:26 PM

Do you have an upgraded fuel pump? If not, you should at least rewire the stock fuel pump. 1G is known for bad grounding and that maybe the cause of your problem. The other thing you may want to check is MAS overrun. However, I doubt it will overrun at 14psi.

CanadianTSi · 10-12-2002, 03:19 AM

A new fuel pump will be my next mod once I save a little cash. I thought that was probably what the problem was, thanks guys.