does anyone know?

 

Hmm, I've never heard of anyone cleaning an O2 sensor before. The element inside that reacts with the exhaust gas is made out of platinum, I guess you could ask a jewler what they use. The stock O2 replacement is expensive, like $200+, but you can use the Bosch Universals they only cost about $40. Unless you have an RX-7 Fashion DP like me in which case only the stock one will fit

 

Thanks for the reply.

I have a new sensor. I put it in my downpipe when I installed my new engine. I was thinking that it may have become too dirty after cranking the engine because of all the oil inside. My car has a rough idle on cold startup. I say rough idle..the needle doesn't move any but I can hear some missing of the engine. I have no engine codes new plugs and wires so it has me stumped.

Later...Scott

 

Hey bro I've got the same problem too, I think. When I start the car when completely cold the car revs up to 3k then drops slowly to about 1400rpms then as the car warms up drops down to about 1050 rpms for about 2 minutes but then climbsback up to 1350 rpm and idels there for about another 1 to 2 minutes(this is when the missing is most noticeable, not really a stumble just slight missing sounds like little pops, the pops aren't really consistent but every 4-6 seconds) there then slowly drops to about 950 rpms and gradually down to base idel 760 rpm. From the moment I start the car when completely cold to car finally drops to about 760 rpm is about 6-7 minutes. I'm using 10-40 full synthetic Royal Purple (RX-7.COM recommended), All NGK 9s, MSD wires, airpump removed of course with mid pipe and 3" exhaust. intake , airpump removed, Greddy Pulley kit, M2 medium intercooler, S-AFC, AC removed from engine bay (condensor, compressor, etc). I thought it might be because I'm using all NGK 9s but it was doing this before I switched to all 9s. Could it be because the airpump is removed? At Idel 750 Rpms vacuum reads 15 on crapometer (Autometer) boost gauge so I figure it really is about 16 or 17(non-ported motor stock turbos). Or maybe I'm just used to a piston motor? Sorry about the thread length...but I appreciate any opinions.....Thanx Tony

 

RotaryMan......I don't think it's because you removed the airpump or your other mods. Plugs maybe I'm not sure.

Mine is missing similar to yours....I start my car in gear....it revs up to 2k..couple of seconds it drops to 1500....the tack stays steady as hell and all I hear is the duh...........duh...duh............duh...duh.....d uh. After my coolant temp hand gets up about 5-7 minutes after startup it calms down and idles at 750-800.

I think you can rule out some of your mods because both of our's is sounding the same and my car is stock except for DP, Fludydine, and K&N filter.

I heard some say the coolant temp sensor or the o2 sensor, but I get no codes. This might sound crazy but I think by having the Fluydine rad my car takes longer to warm up, thus causing the coolant sensor to work later than usual. Maybe I'm wrong but sounds logical.


I will change my plugs this week so we'll see.

Scott

 

ok to clean the o2, buy a new one

the o2 dosent become hot enough to give any reading till abt 5-7 min of idling, so your rough starts are due to plugs, wires or a mulitude of little anoying things, you should never let you car do the 3k startup, its nothign but bad, it was put there to help heat up the stock pre cat( emissions bs) but its no good for the engine, always start in gear, or blip the throtle as soon as it starts, the idle naturaly stays high till the engine is an Normal operating temp or above 170, below 170 deg the car is in cold start mode and keeps the idle higher and the a/f richer to keep it runnin and heat it up....

and as far as it getting dirty from oil, our ehaust temp is WAY higher then oil's flash point, normal ex temps range from arroung 850 crusing to 1200-1300 WOT on a well tuned rotary
most oil flashpoints are arround 450 deg, highest ive seen is 479