Random a/f ratios??

[nek]

So I've never heard of this problem so I'm a little confused.
When I'm driving home from work sometimes( happened first time yesterday). I'll be cruising around 2600-3000 rpm and my car will randomly start to jolt and my a/f ratios will start to go crazy. Then it either returns to normal or stalls out after some time. When I restart my engine it usually goes away. It happened again today again so now I'm wondering. What do you guys think?

 

[clipto]

Do you know if that wideband requires open air calibration?Maybe its time to redo that or check your sensor or tune.

 

[nek]

Yeah it does but I didn't install it that along ago and I don't think the a/f is causing the problem. I think the problem is causing the a/f ratio. You might be right though. Good point

 

[clipto]

I see in your profile you have a ported 16g hotside but what turbo are you running?Unless you mean you have a 16g with a ported hotside in that case you probably wanna add some fuel mods like a fuel pump and bigger injectors and dial in your tune and cruise settings in dsm link.I would recomend 1000cc injectors or 750cc for your 16g and a bigger fuel pump and get it tuned.That should dial in everything.

 

[jtmcinder]

But he said that the issue happens when just cruising, which makes it very unlikely to be an undersized fuel system or boost leaks or that sort of thing. More likely (when still thinking about fuel and air) are things like a clogged fuel filter or a loose MAF connector.

 

[clipto]

Could just be some general maintance but he does have ecmlink so tuning the cruise still could need adjusting.

 

[nek]

Its not the tuning Im sure because Ive been running the same tune for 5 months now and the problem only happened that last two days. My fuel filter is new.
I bought a set of wires off a member and I believe that might be the issue so I am putting my other ones back on.
Ill run it like this for a while and if I continue to have problems Ill post back.

 

[clipto]

Well tunes change over time and weather can affect them, just saying.But if it's not the tune you think then go over all general maintanance.Check plugs, wires, fuel filter, boost leak check, and all the little things and if not check your logger and see if the tune is running good.

 

[LiquidX]

Start with the basics, boost leak test, sensor calibration, IAC test.

Too much red in this thread.

 

[clipto]

Start with the basics, boost leak test, sensor calibration, IAC test.

Too much red in this thread.

Trust me if I could find another color besides red I would be all over it.

 

[nek]

Well tried the wires And that's nOt it. Plugs were replaced over the summer and fuel filter sooner then that. Let's be smart here. A leak would not occur under no boost and if it did the. It would throw off my a/f. My vacuum at idle is strong around -19. a friend said it may be a tps issue and he may be right. I tried to record a cruise lastnight when it happened but my damn CPU failed. Red is nice

 

[nek]

Alright so I took a log today and happened to capture the issue.
The first log I clipped into the issue so its easy to find. (I would like to note that this issue seems to happen at the same distance from work which seems like a time/heat type of issue)

The second is when I started the car back up driving around the parking lot still showing the issue. I believe it stalls at least once in the log.

The third is what a hot start idle looks like for my car just so you guys have an idea of how it should look.

It looks to me like my mafraw is dropping REALLY low when the issue occurs. Please confirm?
If my mafraw is the problem does that mean I need a new gm maf? Or can it mean other things...?

Please help this issue is affecting my work..

Well I tried to replace the gm maf today and it didnt do anything. Great...