O2 sensor and ECU
Christ
12-08-2007, 02:12 AM
I have a feeling this is a stupid question... but I have an O2 sensor code, and I know that means I should change it... that's not the question.. My question is that the ECU keeps blinking code 1, w/o kicking the CEL on.. since it's constantly showing a code, would it be stuck in open loop operation? And could that be part of the reason I'm only getting about 24mpg?
FrodoGT
12-08-2007, 11:33 AM
yup.
Christ
12-08-2007, 03:26 PM
well shit. that explains the lack of power too, or at least the lack of what it used to have... not that it ever had power... but open loop mode, iirc, is a dedicated fuel/ignition map... no advance or anything, it just sets a mode and runs it, correct?
FrodoGT
12-08-2007, 06:38 PM
Well it runs off a set map, with no input from the o2.
Christ
12-08-2007, 09:54 PM
Would that set map explain shitty fuel mileage? and lack of power, etc..
I know one thing tho... when I build the other engine to put in here, I'm def going to take every piece off and completely clean/rebuild it back to BRAND FREAKIN NEW.
Oh, to build a honda engine, are the Honda Spec tolerances tight enough? Or to build something w/ more performance, would I adhere to a tighter tolerance? (I've never bothered to actually BUILD a honda engine, only put parts on them and build stockers w/ minor upgrades.)
I know one thing tho... when I build the other engine to put in here, I'm def going to take every piece off and completely clean/rebuild it back to BRAND FREAKIN NEW.
Oh, to build a honda engine, are the Honda Spec tolerances tight enough? Or to build something w/ more performance, would I adhere to a tighter tolerance? (I've never bothered to actually BUILD a honda engine, only put parts on them and build stockers w/ minor upgrades.)
FrodoGT
12-08-2007, 11:19 PM
Usually if your talking about things like piston rings they have their own spec to follow. Otherwise honda tolerances are fine. And if youve been swapping parts around on your engine and now its running on a map created for that engine with no input from the o2 sensor..yeah itll probably run like shit because it has a set timing and mixture
Christ
12-09-2007, 01:29 AM
yeah, well, it's pry running on a Si map w/ the cam/ignition off, so basically, its' getting way too much air, and using way too much fuel, then not having enough time to exhaust the gasses... go figure.. this is what I get for letting others build their own damn engines when they have no idea what they're doing...
turtlecrxsi
12-10-2007, 10:25 AM
FYI - your sensor could be fubared BUT it could be the wire has lost contact somewhere. The 02 sensor wire is very sensitive. Even with the blinking code 1 it generally won't make that much difference on an obd0car. You may run a little rich. Somebody once told me that it could be the wire is connected/not connected and it won't trip the CEL but it's enough to piss you off if you pay attention to it... GL
EDITED: OBD0
EDITED: OBD0
Christ
12-10-2007, 01:17 PM
Naw, this one is bad... I'll check the wires anyway, but the last time I actually saw this o2, the holes in it were plugged.. well, half of them. I told dave to put another one in, but he didn't want to spend the extra money, not that he spent anything extra on anything else either.. the only reason the head was ported and polished was that he bought it from a shop thinking it was for his CRX... then didn't realise that he could put the A6 head on a B8 if he changed the pistons., then also didn't realise that he'd have to change the ECU, unless he continued using the IM and everything from the CRX HF.. it won't run much of anything if it has a bigger TB on that ECU.
I tried it on my car for kicks.. it has NO power, bucks and jerks, and then when you get to 4000 rpm, it feels like Vtec kicking about 10x harder than it should, and you suddenly have all the pull you need. up to wherever you have to shift..
I tried it on my car for kicks.. it has NO power, bucks and jerks, and then when you get to 4000 rpm, it feels like Vtec kicking about 10x harder than it should, and you suddenly have all the pull you need. up to wherever you have to shift..
turtlecrxsi
12-10-2007, 01:50 PM
BTW, the Bosch 1 wire o2 sensors are the same as the overpriced Honda models :thumbsup:
Christ
12-11-2007, 01:15 AM
Oh, I know, I can use ANY o2 sensor, regardless of whether it's heated or not.. all you have to do is cut off the excess wiring, and match up the sensor wire. If you use a heated one, it will idle funny until it gets warmed up, and you might get a CEL for it.
Christ
12-11-2007, 01:18 AM
Why doesn't my car ever warm up? Any clues? Thermostat is 190* and almost brand new, radiator cap has been pressure tested yesterday, it's 13psi... the car WILL NOT warm up to operating temp.. even on a warm day. (around 50-60 degF.) only time it does, is when I'm revving it down the highway in 3rd gear or so, keeping it up to 3k+ RPM... as soon as I shift into 5th, drops the RPM to around 2000-2200, and the engine starts cooling down..
I can't keep the heat above about 1/4 of the thermal indicator. (heat gauge)... it sometimes will cool right down to the cold line while I"m on the highway.. and there isn't a bad connection there either, checked that as well... literally, you can tell when the engine is cooling down, b/c the heater starts not "heating" lol. it's not that bad, since it's only a 20 min trip to/from work, but it's irritating, and cold run mode causes higher fuel consumption.
I can't keep the heat above about 1/4 of the thermal indicator. (heat gauge)... it sometimes will cool right down to the cold line while I"m on the highway.. and there isn't a bad connection there either, checked that as well... literally, you can tell when the engine is cooling down, b/c the heater starts not "heating" lol. it's not that bad, since it's only a 20 min trip to/from work, but it's irritating, and cold run mode causes higher fuel consumption.
FrodoGT
12-11-2007, 01:24 AM
Yours is a little worse than mine because its colder there, but mine never gets past 3/8th of the meter. My heat will burn me, literally. Shit my crx wouldnt even go much past the line on the highway in the winter..had a BIG MUTHAfreakin fluidyne radiator. Even in the summer I sat at 1/4. I figured as long as vtec kicked then it was warm enough.
Christ
12-11-2007, 01:26 AM
dude, my heater barely gets hot... I mean, it's redix, stock radiator, the fans come on @ stock 210.. (I think) they NEVER come on.. I can idle the car all day, the fans will never come on.. it NEVER hits op-temp. Even during the summer. It used to before we rebuilt the engine and shit, but it hasn't ever since then.
FrodoGT
12-11-2007, 01:29 AM
My fans are always forced on..maybe your thermostat is stuck open?
Christ
12-11-2007, 01:36 AM
That's possible, I haven't checked it... I just wanted to figure out why it was staying cold.. and I didn't even think of that, b/c the thermo has only been in there for less than 20k.. but I've heard of it happening before.. I'll check that out, and clean/replace as necessary... wanted to replace all the gaskets on the engine anyway. except I'm taking each part and getting it milled to accept an O-ring... so I don't have to use gaskets, I'll just use huge O-rings in place of each one. that and rubber cement have always worked perfectly for me.
Once I get the A1 built, and put in the car, I"ll pry be selling parts off this engine, b/c I'm using a diff engine for the Honda-Kart.
So I guess I won't do the O-ring thing on this one, I'll just get it done while I"m having the block/head milled for the A1.
Once I get the A1 built, and put in the car, I"ll pry be selling parts off this engine, b/c I'm using a diff engine for the Honda-Kart.
So I guess I won't do the O-ring thing on this one, I'll just get it done while I"m having the block/head milled for the A1.
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