Weird Problem: Whacked A/F ratio and messy idle

[Skuce]

Ok.

I put in a new clutch on Saturday. Then after that there are a few very odd problems that i can't pin down.

First off. VERY erratic A/F ratios. I mean totally random.

One moments it's going perfect in the 14.9 area. Then over a period of about 3 seconds. It just goes straight to super lean 18.0 or off the scale. The part that gets me is that it's slow to do this.
Now if i mat the gas to put it into WOT. it only goes 13.0 rich about 40% of the time. No way to predict when it will do it. Then right after one of 2 things will happen. it will either A) creep back to full out lean in about 3-4 seconds B) it will go back to normal 14.9 and hang out there for a while.

Now the second problem. Idle is wonky.
Probably has something to do with the 1st problem and the motor just not acting right.

Also....how much effect on A/F's does ignition Timing have? Cause I caught my buddy messing with my timing light and had a 12mm in his hand when I was having supper.




motor specs: 1.8l BP, stock ECU, BP26 cams, Spec 3 clutch. That's it.

[atomicEGT]

punch buddy in kidneys, reset timing. proceed from there.

[Tazman2]

punch buddy in kidneys, reset timing. proceed from there.

PS: I'd also make sure to reset the ecu considering your "buddy" messed with your timing the incorrect way and the ecu is probably gonna be confused from now on anyways...

[Lex]

Sounds a little weird - is your O2 sensor hooked up properly? It sounds like an electronics bug and I don't think timing can cause such a crazy change in A/Fs.

BTW, what A/Fs do you see at WOT steady when NA?

[Skuce]

12.8 - 13.4 at WOT and it's usually pretty steady.

And yeah. i put the timing back to the point where it was before. I just roatated the disty back to where the old marks were on the channels. Car runs back in the 14.6-15-8 range at crusing.

Still have to do an accurate set on the timing sometime....But there isn't a single mark on my crank pully. No little groove or anything to line up with the timing guage.


Oh...and yeah. it's an AEM wideband that I have setup to run my stock ECU

[Lex]

Make sure the wideband is giving the ECU the right information.

I run a stock narrowband to my MS for stoich and the wideband for tuning.

[FE3-323]

id check the sensors might not be functioning right

[jenfre]

chek the MAF when something oes wrong on my 323 with mesy idle and wrong A/F it something to do with a sensor and the MAF often

[Blinks323]

Hey,
As you know I had my aem o2 hooked up to my ecu aswell, and had the same problem your having. I got pissed off with the way it was running so I welded in another bung and put my stock o2 back in and ran my other just for reading and has solved my problems.

Good Luck, Steve

[Tazman2]

Hey,
As you know I had my aem o2 hooked up to my ecu aswell, and had the same problem your having. I got pissed off with the way it was running so I welded in another bung and put my stock o2 back in and ran my other just for reading and has solved my problems.

Good Luck, Steve

AEM is making o2 sensors now? Yikes... thats like fisher price making condoms... BAD!!!!

[bcrx7]

Are you sure your airflow meter is hooked up right and is not leaking? Even an oxygen sensor not working should not make the car idle weird.

[Tazman2]

Are you sure your airflow meter is hooked up right and is not leaking? Even an oxygen sensor not working should not make the car idle weird.

Actually depending how bad it is it actually can. Normally when it goes it makes the car run real rich. If it throws a code the car freaks out and goes into limp mode. Ie rough idle, etc.!

[LisaT]

when i put my new engine in my o2 sensor wire got grounded out and car would barely idle.