i have searched, vacum leak?, maybe timing?....i can't put my finger on it, but i have unburned gas coming out of my exhaust...and i can't figure out why, its an 88 n/a with no mods at all, gutted cats, and when ever i put it in gear it launches foward, and stalls....i can't figure it out, i have tried a lot, and now im going for second, third, fourth(and so on) opinions

-Thanks,

Sean

 

anyone have ANY suggestions?

 

-- TPS failsafe is fuill throttle (dumping... pouring gas into the intake)

-- O2 failsafe will cause pig rich idle

--dirty as hell injectors not atomizing (squirting instead of spraying)

--maf failsafe could be an issue


Pull the CEL codes, you'll probably knock out the possibiliy of all but oen of the above

 

Maybe one of your injectors is stuck open

 

replaced the o2 sensor already, umm no codes are being spit out, umm i'll see what i can do to check that list.

thanks

 

The O2 sensor does not effect idle at all.

There are many reasons the car could be running rich. Eliminate the simple causes: vacuum leaks, change your plugs and air filter. Do a full tuneup.

If you suspect leaking injectors, pull the intake manifolds and injectors, jumper the test connector at the passenger shock tower and turn the key to IGN. This test connector allows the fuel pump to run constantly. Any injector leak will be immediately apparent.

 

****In gear and launches fwd**** isn't that a case of either a clutch slave that needs bleeding/rebuild, OR ???????

 

Is it an auto?

 

auto i have the manual thats going in soon, but its still auto

 

would that injector cleaner you mix with your gas in tank work?

 

Keep in mind that sometimes injector cleaner makes matters worse (been there, done that, as well as others on this forum), especially if the original problem is a fuel system component clogging. If you're going to use it, go with the Chevron Techron stuff, it's the only cleaner I've heard good things about...

 

thanks for the correction

 

That or the redline stuff.

 

it does affect idle, thats why they run wierd when you pull off the air pump

 

whats the air pump have to do with the O2 sensor? the O2 sensor is inches from the block whereas the smog pump's pipe runs down to the cat, way past the O2 sesnor. am i missing something?

also, i believe the O2 sensor, like a catalytic converter, doesn't function until a certain temperature. cold start/revving warms the cat faster for emissions, and the O2 sensor, which also affects a cars performance (which includes emissions) as well.

 

The pump's pushing air into the exhaust ports at the rotor housings, which will affect the mixture the O2 sensor sees, I think that's what j9fd3s means

The ECU will ignore the out-of range O2 sensor outputs for a while until the heated exhaust gases bring it to its "operating temp"...I can sit & watch my O2 sensor check code go on continuously for 3 or 4 minutes after a cold start, which means the sensor is pushing voltage already, but not in the limits the ECU wants to see for fuel scheduling...

 

i havent seen where the air pump pumps air pre-O2. i need someone with a pump to show me. i'm kinda curious now.
and thanks for verifying that there's an operating temp for the O2. i was 99% sure, but that 1% always makes me say 'i think' or 'i believe' or something along those lines.

 

Hook a meter up to the O2 input on the ECU and drive around- you'll learn all about it what it does just watching the readings (also an effective troubleshooting approach if you think the sensor might be bad)

Before the pump air gets routed to the cats via the split-air pipe (5th gear, I guess), it's all being dumped into the exhaust air, or out the relief valve...This is also the source for our EGR system air, I believe...

 

the switch in the bottom of the radiator turns on the 02 sensor on the gsl-se and s4's, the s5 is smart enough on its own.

the air pump air gets injected into the exhaust ports at idle, this throws off the o2 reading, the ecu will try and compensate if the air pump air is not there. some more than others, fd's run really bad with no air pump

 

IIRC (hehe), the S5s dont have an EGR setup.

 

Thanks guys, now that we cleared that up......kidding, im going to send my injectors out to get cleaned, thanks for the help guys, much apreciated(sp?)