Well i was on my was to my gf ( like 40 miles away) and half way there check engine light came on, now why would it do that ? I know my car has alot of problems, low compression in all cylinders, it hesitates at low rpms( o2 sensor failing), and 3rd cylinder wouldnt spark at all. After the CEL came on, i didnt feel a thing different in performance, maybe it even became a bit quicker somehow. So what is the reason for my ecu to throw a CEL (for any ECU for that matter, when does a check engine light come on?) , should i be worried, or just ignore it?
Thanks

 

I guess I could be the master of the obvious, here.
But, the cel comes on whenever the ecu sees an anomoly in sensor
signals. Are you OBD0, 1, 2 or 2B?

 

Well, i have no clue, and never really cared, im the kind of guy who goes to mechanics to change oil, and thinks that kicking the car can fix the problems
Its a honda civic coupe 1995, and the engine is 1996 h22a2
So if my o2 sensor would be failing in some way, it could throw a CEL, right?

 

I wouldn't call myself a mechanic either.
More like a tinkerer, mostly out of neccssity, rather than desire.
After paying so-called mechanics lots of $$$$ to F!@#$% up my car.
I thought I could F!@#$% up my own car for free. LOL
Anyway, in my albeit ,limited experiece. If you can detect nothing wrong,
it's USUALLY the o2 sensor/s.
I'd still have it checked by a mechanic, though to be sure.
In my state if the CEL light is on you can't pass safety inspection.
HTH
If it's throwing the o2 code it probably needs to be replaced.

 

I always wanted to do the same, but never really had the place to do it on my own, for ya.
There is no tech inspection in UK, so it doesnt matter as long as i dont stall on a motorway

 

IF it's JUST the o/2 sensor, you are not in imminent danger of dying
on the motorway.
But get it checked by someone who knows how to read honda ecu codes.

 

Well i made it no problem, but you know whats funny ? Today morning i topped up my oil ( it was well below the middle mark on the feeler) which was right at the middle of max and min marks, i drove the car around for 2 hours, let it cool down for half an hour checked it, and it was in the middle again ( so i take i did the job fine ), now after 40 highway miles driving, i went to get my gf and let my car sit there for another half an hour, so i come out and check my oil again, and its 2 times over my max mark! ( i checked that 3 times to be sure). I guess i should've took it to the honda dealer and them change it for me for 70$
Any idea?

 

maybe its not b/c you are low in oil. but low in oil pressure. have you damaged your oil pan in any way? or there might be a disruption in flow from the oil pan to the motor....

 

OK, i guess its time to throw the engine away and get a new one

 

Its just ******* crazy how much money i put in this car, and still dont have a proper running motor, im tired of that ****

 

Ok, I'm willing to help but you have to cooperate and get the right CEL's and be able to fix the problem.

What CEL's are you getting?

If you're getting the O2 sensor code, I would recommend you replace the O2. It's very simple to do.

As for not sparking on the #3 cylinder only, sounds like the cap is worn out, and I would recommend you replace the cap/rotor, as well as plugs and wires.

 

Throwing code 43, i've been told by a honda dealer that it stands for o2 sensor
How serious is the oil problem, is it gonna cost me a buck?
Im just trying to figure out what'll be cheaper to do, with all the problems that i listed and i need to fix, and now the oil one adds up to, wouldnt it be cheaper to get the new engine, which is prolly gonna cost me 400$, and to fit the engine is around 300$ as well ?

 

Code 43 is Heated O2 control. Which goes to the A6 pinout.

That is the WHT wire. Make sure there is no corrosion on the wire and leading properly to your ECU checking with a digital multimeter.

If wiring shows to be good, and there is no open circuit, then I would recommend you replace the O2 sensor which is about $40 bucks.

It's very simplle. You simply unplug the connector, unscrew the O2 sensor in your header, and reverse the process.

What is the deal with the oil? Just burning oil? Sounds like the piston rings are properly shot. How many miles are on the motor?

 

Read a couple lines above, poison, thanks for the help, appreciated. btw, i never saw no sensor, nor the wires coming into the header, is it hidden below the header somewhere ?

 

Just so you dont have to scroll anyway :
Today morning i topped up my oil ( it was well below the middle mark on the feeler) which was right at the middle of max and min marks, i drove the car around for 2 hours, let it cool down for half an hour checked it, and it was in the middle again ( so i take i did the job fine ), now after 40 highway miles driving, i went to get my gf and let my car sit there for another half an hour, so i come out and check my oil again, and its 2 times over my max mark! ( i checked that 3 times to be sure). I guess i should've took it to the honda dealer and them change it for me for 70$
Any idea?

 

Sounds like you have too much oil in the motor. Drain a little.

The O2 sensor on the H22 header is located near the cat on the header collector.

It's most likely the problem is either a bad O2 sensor, or the wiring was done wrong when you or someone else extended the wires to reach the new H22 O2 sensor (assuming you adapted the Civic EX harness).

 

Do you think a bad o2 sensor could also be the reason of bad compression #'s?
110 135 145 110, or is it not correlated at all ?

 

Nah, not necessarily. If you're not burning oil, and have shitty compression, that is a sign of a bad head gasket. The O2 sensor just gives the ECU a lot better A/F ratio's.