KA-t cant keep steady airfuel ratio

[dorifto-san4o8]

I have a 95 240sx with a turboed KA. I recently put on a wideband o2 to see where my airfuel ratio is at because my car flashes CEL constantly while driving (cruising) and never in boost. SO just say im cruising at 65mph @3000rpm my afr goes from 14.6 then all of a sudden goes to 16+ back to 14.6 and sometimes dropping to 13s. So i found out that everytime it drops or rises my CEL flashes. But while in boost no CEL lights flash and afr stays at a constant 11.9

Same thing goes for my idle. Although i keep a steady 800rpm plus or minus 10rpm my afr goes from 14s to lean. .

This occurs when my car is at full operating temp. Im holding a steady vaccum of 22 and i did clean out my iacv valve. Has anyone had this problem? Im tuned with efispecialist ecu and safc.

thanks

[dorifto-san4o8]

Wideband is brandnew and i just recently changed my o2 sensor.

[nicku]

i have the same problem at idle. but since it is at idle, i dont really care

[dorifto-san4o8]

it also does it while driving off boost. Its just sucks seeing my check engine flash.

[NI_YON_Zenki]

Diagnose the PCM, check for the trouble code. its probably due to miscalculations of fuel, not air. lean misfiring.

[dorkidori_s13]

prolly a MAF problem...theyre VERY touchy little things

it may have alot of to do with the filter youre running if your still MAF based on your KA...try removing the filter from the MAF and making a few cruising passes while watching your widebands A/F read outs...cheap air filters cause TONS of air flow problems with MAFs

[NI_YON_Zenki]

prolly a MAF problem...theyre VERY touchy little things

it may have alot of to do with the filter youre running if your still MAF based on your KA...try removing the filter from the MAF and making a few cruising passes while watching your widebands A/F read outs...cheap air filters cause TONS of air flow problems with MAFs

If he had problems with the MAF, would he not be reading an enriched state, below 14.7:1? if his MAF is reading accurately, he should see a lean state, no?

I would assume his MAF is upgraded with the turbo'ed upgrade.

[dorifto-san4o8]

The CEL code is 77 which is rear o2 and it is a new o2. CEL only flashes when car leans out. Im running a z32 maf and hks intake filter. Maf is about 12 inches away from turbo

[EDT007]

It can be a exhaust leak pre-wideband. Just check to make sure. I know I had a similar problem on my GSX. Goodluck. While you're at it, it would be a good time to check for boost leaks too. :2f2f:

[dorifto-san4o8]

prolly a MAF problem...theyre VERY touchy little things

it may have alot of to do with the filter youre running if your still MAF based on your KA...try removing the filter from the MAF and making a few cruising passes while watching your widebands A/F read outs...cheap air filters cause TONS of air flow problems with MAFs

any way to test if my maf is still good. I got 1 day until the J style comp to get my car working better.

[dorifto-san4o8]

It can be a exhaust leak pre-wideband. Just check to make sure. I know I had a similar problem on my GSX. Goodluck. While you're at it, it would be a good time to check for boost leaks too. :2f2f:

i checked for exhaust leaks and didnt find any. I also checked my injectors and they dont leak at all. i cleaned the iacv valve. Could the iacv just be bad because i noticed my idle doesent change much when adjusting the screw?

[nicku]

i have bad exhaust leak before the wideband sensor.

[dorifto-san4o8]

anyone in san jose that has a z32 maf that i can try out? I did buy my maf used so maybe that could be the problem.