when i got my tII i was always running normal to rich. i got the a/f guage red orange green. and i had to change my starter and decided to change the oil too. after doing this my guage was always jumping from norm orange to red lean just back and forth. is this normal after changing oil. i stayed at 20 50 which the previos owner always put. do any of you guys know wat could of happend

 

how's your wiring? if you got a bad ground or bad wiring anywhere from rewiring the starter that could **** any electronic stuff up.

 

you know that narrow band afr gauges are useless on our motors, don't you?


Unless it is a wideband, the gauge will "sweep" all over the place.

 

You either moved the main engine ground or you didn't connect it back correctly.
Was there a thick black wire with a large "lug" on one of the starter bolts?
That's the main engine ground.


-Ted

 

alright i went and jacked up the car again and checked the main ground and started tightening it a lil more and the whole peice broke off omg so im guessing the ground was straight to begin with. so i gotta wait till tomorrow to get a new starter cuz it was under warrenty. when that shyt broke sparks went everywhere almost got my ***

so ima jus put the starter in tomorrow and chek all the fuses

gotta question on the wide band do u know any cheap widebands arround and if i get that sensor do i still keep the guage how would i go about doin this

 

Well, the large wire ON the starter is 12vdc directly from the battery. They were not talking about that wire which is held on with a 13mm wrench size nut.

They were talking about the large ground wire from the battery. It MIGHT be attached to the LONG bolt for the starter or in some cases another bolt just above that one, that holds the trasmission to the engine.

The wide band...............you'll chunk the sensor and gauge you now have. The wide bands are relatively *cheap*. But only *cheap* when you compare the cost of one now vs say ten years ago.

 

I wish people would stop saying this. A regular A/F gauge is far from useless. True, you will never use it to tune. But it is a great device for telling you at a glance whether you are stupidly rich or stupidly lean. Also, that "sweeping" is how you know you are in closed loop, where you should be driving to get the best mileage.

And what most people don't mention is that many wideband sensors have a very limited lifespan of about 20K or so. After which they start to drift. Replacing a wideband every 20K gets expensive...Alot nicer to use the wideband for tuning, and then switch to the regular narrow band when done.

 

Yeah, read a little about them. Narrow bands will sweep back and forth on piston and rotary engines. It's a good way to make sure you're not in danger of detonation.

I didn't know about the 20K lifespan though... kinda scary. I guess I'll be buying one and using the wideband strictly for tuning.

 

I was debating wiring up a custom device with my narrowband sensor when I get a turbo in the project car.

It would take the manifold pressure and the O2 sensor voltage. Under boost, a narrowband O2 sensor should be pegged rich. If the sensor voltage dropped below a set point (0.7v or so) while the manifold pressure was high (in boost), it would do *something* to handle it - tweak the coolant sensor output, sound a buzzer/light, or possibly even cut the ignition. I'd obviously have to make sure it was working properly before adding an ignition cut, and since the O2 sensor output lags what the engine is actually doing, it might not be quick enough, but if it works properly, it'd be a knock sensor with teeth that could actually (hopefully) take action fast enough to save the motor.

-=Russ=-

 

02 sensors are pretty isntant.

 

In terms of detonation prevention, they're still a bit delayed. They read the exhaust AFTER it comes out of the engine.

-=Russ=-