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cs daytona
04-04-2007, 07:42 AM
i just bought a ews guage from 3barracing.com and dont know if ny gauge is acting up. i have an 89 dodge daytona shelby t2, a520. i installed a 2.5l common block and i'm still running on unmodified 2.2l electronics and fuel system. ok, i KNOW i'm running lean! at idle/cruise/slight accel its flashing thru all the lights as i expected. but when i hit wot its blue indicating rich. is this possible? it would be nice to know if i am running rich but theres no way with my setup. i have all my connections soldered and running to straight battery. theres no way to have anything backwards is there? thanks for the help guys!

travis vela
houston, tx

Murphy
04-04-2007, 10:18 AM
what are you doing for injectors, fuel pressure regulator, fuel pressure, fuel pump, how old is the o2?

Clay
04-04-2007, 10:59 AM
Ok, first thing you need to know is that the dawes devices O2 gauge only reades from 0.90 volts and up. So everything below .9 volts shows as a red light, ie lean.

So if your lights are bouncing around while your driving, then your getting readings above .9 volts all the time, which I find weird.

Now if thats true (ie your getting readings above .9 volts during idle and cruise), then I dont have an issue believing you are pig rich at WOT.

clay

turbovanmanČ
04-04-2007, 05:34 PM
Ok, first thing you need to know is that the dawes devices O2 gauge only reades from 0.90 volts and up. So everything below .9 volts shows as a red light, ie lean.

So if your lights are bouncing around while your driving, then your getting readings above .9 volts all the time, which I find weird.

Now if thats true (ie your getting readings above .9 volts during idle and cruise), then I dont have an issue believing you are pig rich at WOT.

clay


My DD will bounce into the red when driving, thats normal and the way the oxgyen sensor works.

To see if indeed your are rich, do this test, warm up the car, let idle, now go grab your propane torch that everyone has, find a place to inject it but DON'T create a vacuum leak, now fill the engine so it starts to run rough, if the DD is now pig rich, IE Purple or Green, the ox is working and hooked up correctly. If no, then the sensor is bad, or you have it hooked up correctly.

cs daytona
04-04-2007, 10:34 PM
what are you doing for injectors, fuel pressure regulator, fuel pressure, fuel pump, how old is the o2?

i have stock t2 injectors and pressure reg. i crushed my regulator today to gain 10 psi (1/8 inch), my pump is a walbro 255lph unit. my pressure is 60 at idle (after crush). as far as my o2, its the one that came with it when i bought it last year but i have another i can try.

also is it normal for the lights to go out when they go out of range? or does it stay red or blue when the ecu is compensating?

and also (sorry to drag it on) would a slightly leaking turbo seal cause strange readings on the o2?

thanks

travis

turbovanmanČ
04-05-2007, 03:37 PM
i have stock t2 injectors and pressure reg. i crushed my regulator today to gain 10 psi (1/8 inch), my pump is a walbro 255lph unit. my pressure is 60 at idle (after crush). as far as my o2, its the one that came with it when i bought it last year but i have another i can try.

also is it normal for the lights to go out when they go out of range? or does it stay red or blue when the ecu is compensating?

and also (sorry to drag it on) would a slightly leaking turbo seal cause strange readings on the o2?

thanks

travis

If you go too lean, the lights will go out, meaning LIFT NOW.

A leaking turbo into the exhaust will coat the ox sensor with oil and kill it.

cs daytona
04-05-2007, 05:51 PM
I have never had the red light on when its at wot or 75% or more throttle. it has always been blue and stayed blue. i'm just wondering if the dd would also tell me if the o2 sensor is f'ed up

turbovanmanČ
04-05-2007, 05:58 PM
I have never had the red light on when its at wot or 75% or more throttle. it has always been blue and stayed blue. i'm just wondering if the dd would also tell me if the o2 sensor is f'ed up

Its quite possible, do the test I told you to do.

gti_7
05-25-2007, 12:08 PM
If you go too lean, the lights will go out, meaning LIFT NOW.

A leaking turbo into the exhaust will coat the ox sensor with oil and kill it.


ahh.. so thats what that means.. i recently swapped fpr's and it took my computer a while to relearn or something .. i would be lean all over the place under mild boost [5psi] during the day.. and at night it would be fine.. [green/yellow] It did this for about three days and now its back to it being yellow/green Leds.. i was wondering why the lights on the dawes would go out after about a hour of driving around town-no boost.. now i know! i thought my O2 was done or a wire melted or something..

the only time it leans in the red now is when its humid out.. drat! there was a fox body stang 'vert last night i wanted to have fun with too! lol

bernard

cs daytona
06-08-2007, 07:41 AM
update guys.......

i've been putting it off but got back to it. i replaced the fpr with a stock bosch replacement and it ran a whole lot better! i could even run closer to wot without it loading up and shutting down. i got a little daring and i removed a vacuum cap and drove it. MAN what a difference!! it leaned it out just right! and that fool had some balls and it revved soooo much quicker than before. so looks like im still rich. i'll figure something out....... :/

travis

Aries_Turbo
06-10-2007, 08:34 AM
i suggest getting the correct computer for the engine thats in there. then you wont have to fool around and guess if its ok. :) plus the 2.2 timing is a little aggressive for the 2.5L. dont want to see it pop. :)

Brian

cs daytona
06-10-2007, 09:57 PM
well i have already flashed an eeprom with 89 t1 2.5l data on it and it ran a whole lot better but still shows to be rich and will load up and pop. the only thing i havent tried is injectors.

travis