I start my car up, no CEL, it warms up, rpms drop, after awhile CEL comes on. shut off and restart motor, no CEL, let it idle for awhile, comes back on, so i tested it with the motor running and this is what i got...also my redline seems to be at 7500rpm no matter if the CEL is on or off, what could be causing that?? 94 b18c1 with (as far as I know) stock p72. Anyone know whats going on? I understand the code 8, but I dont know what code 41 means...any help would be nice! Thanks
8 TDC - top dead centre sensor
41 Primary oxygen sensor heater

 

The O2 sensor has a built-in preheater. Check the 2 same-color wires on the sensor. They should measure 10 to 40 ohms between them, & neither one should have any continuity to ground. If that's not OK, buy a new O2 sensor.

If that's OK, then you gotta look for shorts or opens in the car's wiring for this circuit.

 

what does the pre-heater do? heat the sensor? i live in florida and it got down to 28 degrees last night, (coldest night/day this season) would that have anything to do with it?

 

no, the sensor needs to get up to maybe 1500 deg.F before it starts working. Back in the late 70's the sensors were simply heated by the exhaust after a couple minutes. With a preheater they come up to working temperature in probably less than a minute. EPA rules...

 

jebus, thats hott y0! other people are telling me that the rpm thing sounds like i need a new distributor, whut do u guys think?

 

I thought the rpm was limited to 7700??

 

no, stock gsr redline is 8100rpm

 

the top dead center sensor is in the distributor and is not available seperatly. The tach also uses one of the sensors in the dist for its signal, maybe the tdc sensor is %#$@# up.

 

1500 degrees F? holy ****. aluminum melts at 1400.................

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LSTEG96 &raquo;</TD></TR><TR><TD CLASS="quote">1500 degrees F? holy ****. aluminum melts at 1400.................</TD></TR></TABLE>I was sorta guessing, maybe that's high. But the sensing element has to get way hotter than the exhaust pipe metal. The aluminum (exhaust ports in the head) are kept cool by their water jacket. Those surfaces never get nearly as hot as the exhaust gas temperature.

 

check the wires to you O2 and make sure the plug isn't pulling apart.

i would also check the timing, the belt may have jumped.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by blkb18 &raquo;</TD></TR><TR><TD CLASS="quote">the top dead center sensor is in the distributor and is not available seperatly. The tach also uses one of the sensors in the dist for its signal, maybe the tdc sensor is %#$@# up. </TD></TR></TABLE> this sounds like the culprit...
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by campbuds &raquo;</TD></TR><TR><TD CLASS="quote">check the wires to you O2 and make sure the plug isn't pulling apart. i would also check the timing, the belt may have jumped.</TD></TR></TABLE> i messed with the o2 sensor the other day, and everything looked good as far as i could tell...drove the car for a good hour today, running errands, no CEL...i guess i'll replace the distributor, cap and rotor, etc. and check the timing...we'll see whut this does, thanks guys, if i still have problem, i'll be back...now i just have to find the time to do this