New to Efi Live

[cvhu]

hi guys i am new to efi live as the title states, i have a 78 camaro with a ls1 and a 4l60e tranny, the car has run great for 4 years now and has just started some surging issue while acceleration, i have logged a quick little run and was wondering if i post the tune and log if some one could look at and maybe pin point the issue for me. any help would be appreciated

[joecar]

Looks like MAF is under-reporting.

Were you running closed loop trimming...?

[cvhu]

sorry joe i was away for a few days, but like i said i am new to this i bought efi live to log what was going with the car, the tune was done by some one else so i am not sure if it runs in close loop or not... i wish i could tell you more, i am reading and learning about it but is going to take awhile, how does the tune look by the way??thanks

[GMTECH4]

if the car ran good for four years I wouldn't think it would be the tune. check for vacuum leaks behind the maf also you need to log some more pids also look for misfires

[joecar]

+1 on what GMTECH4 said.


Your MAF sensor might be dirty (what air filter do you have...?)

[cvhu]

what pids do you recommend i use , i just used what was set up in efi live, and i am using a spectra air filter, again thanks for the help and patience

[joecar]

what pids do you recommend i use , i just used what was set up in efi live, and i am using a spectra air filter, again thanks for the help and patience
If this filter requires applying oil to the filter element, then this oil can contaminate the MAF sensor... you have to minimize oiling the element... and you have to clean the MAF sensor frequently.

[joecar]

Log these pids:
SAE.MAP
SAE.MAF
SAE.RPM
SAE.TP
SAE.LONGFT1
SAE.LONGFT2
GM.HO2S11
GM.HO2S21
GM.IBPW1
GM.IBPW2
GM.MAFFREQ
GM.EQIVRATIO
GM.MFTOTAL
GM.KR
SAE.SPARKADV
SAE.IAT
SAE.ECT
CALC.CYLAIR
CALC.INJDC1
CALC.INJDC2


remove SAE.O2S11, SAE.O2S21.

[cvhu]

thanks joe i will try those pids, also i dont use oils on my filter

[joecar]

Clean the MAF anyway (use CRC MAF cleaner) and see what it logs.

[cvhu]

i just cleaned the maf and there was some oily residue i front of the maf i will have to log it later as it is raining hard here right now, thanks again for the help joe

[cvhu]

well here is another log after cleaning the maf and searching for leaks after the maf. i couldnt find any, i loaded the pids you said to use, i need to learn what all this data means...someday maybe

22294

[joecar]

At 70+% throttle and 6000 rpm MAF should read something like 260+ g/s... yours shows no more than 200 g/s.

LTFT's indicate airmass is low.