code 1 and 16, 89 civic
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code 1 and 16, 89 civic Hi,
so my car will start it's a 89 civic with the 1.5L throttle body. The ECU is giving me code 1 (O2 sensor) and code 16 (fuel injector)
Ive read a lot on google and they say it's the main relay but i just bought a main relay because it wouldn't even start before.
when i put the new relay in it still wouldn't start so i took the injectors out and just tapped them a little with a screw driver put them back in and it started. but now when i give it gas it either stops at a certain RPM or wont rev at all and die.
I ran fuel injector cleaner threw it and it runs slightly better but still not drivable in town.
Could the O2 sensor cause this behavior? Any advice?
so my car will start it's a 89 civic with the 1.5L throttle body. The ECU is giving me code 1 (O2 sensor) and code 16 (fuel injector)
Ive read a lot on google and they say it's the main relay but i just bought a main relay because it wouldn't even start before.
when i put the new relay in it still wouldn't start so i took the injectors out and just tapped them a little with a screw driver put them back in and it started. but now when i give it gas it either stops at a certain RPM or wont rev at all and die.
I ran fuel injector cleaner threw it and it runs slightly better but still not drivable in town.
Could the O2 sensor cause this behavior? Any advice?
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Re: code 1 and 16, 89 civic
No, the O2 sensor doesn't affect the fuel trim that much. I think your injectors are bad but, check fuel pressure first just to be sure. Fuel pressure should be around 40psi. If it's not, then change the fuel filter. If that doesn't work, change the fuel pump. I recommend here for parts: http://www.hondapartscheap.com/southbay/jsp/home.jsp Don't have a heart attack at the price. Instead of paying $300, if you live close enough get some used ones for near nothing here: http://www.picknpull.com/default.aspx
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No, the O2 sensor doesn't affect the fuel trim that much. I think your injectors are bad but, check fuel pressure first just to be sure. Fuel pressure should be around 40psi. If it's not, then change the fuel filter. If that doesn't work, change the fuel pump. I recommend here for parts: http://www.hondapartscheap.com/southbay/jsp/home.jsp Don't have a heart attack at the price. Instead of paying $300, if you live close enough get some used ones for near nothing here: http://www.picknpull.com/default.aspx
If it's the injectors which one would cause it not to rev up? or could it just be both of the injectors
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From: Funkytown, Tx
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I honestly don't know but, I do know those injectors are probably old and worn out. If you replace one injector it could overwhelm the other injector. I recommend replacing both to ensure adequate fuel delivery. Sorry, I know it's a lot of money.
btw: Don't take my word for it, get a second opinion.
btw: Don't take my word for it, get a second opinion.
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yeah probably and the car has been sitting around not driven for 10 years so that probably doesn't help either.
Just sucks add on another $300 to the $1500 I've already put into it.......
Just sucks add on another $300 to the $1500 I've already put into it.......
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Hello all. New member here. First I'd like to say that I have a 1990 Civic DX with 263,000 miles. Until very recently it has been amazing. It has never had an engine or transmission rebuild of any kind. Typically it achieves from 35-42 mpg, and averages around 37-38. It also burns less than 1/2 a quart between oil changes. Amazing engine! For the most part, anything that has been replaced on the car was due to decay and rust--rubber hoses, radiator, fuel tank, AC condenser, CV boots, ball joints, etc. Fuel filter was replaced a few years ago. Clogged solid!
Anyway, pertaining to this thread, I am also getting the 1 and 16 codes. Until this year I didn't even know how to read the codes (and didn't care, really, since I never had any major problems), but now that I am getting a CEL repeatedly, I have found out how to read the codes.
For many years now, if I were to jump right onto the freeway with a cold engine, the CEL would come on. Flick the key, and it goes out. No more worries at all at any time. Warm the car up amply, and the CEL won't even come on. I have no idea what it was setting for because I never paid attention.
Now two summers ago it started setting codes all the time, and I figured out what they were (1 and 16), and so I bought a ton of fuel injector cleaner and ran it through the system. I also disabled one of the injectors so that the other would do all of the work, and all of the cleaner would be forced through it. After repeatedly doing this, the CEL stayed off until just recently. Now it's the same codes again.
I decided to hook a digital meter to the O2 sensor to have a look. This is what happens: at idle voltage holds in the 80s. Seems normal. Keep the mixture around stoichiometric for a smooth idle, and the O2 sensor can cool down, so it's best to ignore it. Then while cruising and driving, voltage swings high and low repeatedly, which seems normal for driving. However, when coasting down a hill, but maintaining speed, with the throttle almost all the way closed, mixture reading climbs to idle reading-- .88 volts or so. If the voltage stays at this high steady reading for over 10 seconds, the CEL sets. Likely in a modern car it would set a 'O2 sensor high voltage' code, or 'rich'.
Well I read online that the injector O rings can leak, and so I thought that this might be causing the mixture to go rich. However, if I completely let off the throttle while coasting, fuel cuts out completely, and the O2 sensor voltage drops to 0. That said, I doubt that the injectors are leaking in any way, as cutting them off would not stop a leak past the O ring on the side of the injector, where fuel pressure is still present. Also, fuel mixture at all other conditions is fine, and the car does not lope at idle. It idles like a brand new engine.
Fuel pressure is fine. I tested it. It falls within range, and holds residual overnight, indicating no leaks.
I tested the TPS and MAP sensors for basic functionality. The TPS voltage/resistance changes smoothly, and the MAP sensor voltages match closely to recommended voltage/vacuum readings.
I guessed then, since everything seems to be fine, that perhaps the TPS might still be inaccurate near the closed throttle position, since this is the area used most often. ....So I adjusted it. I tried advancing it. I was actually able to just get the system into closed-loop (up-down-up-down) mode at idle, and I backed it off until it just went into open-loop mode (no rich-lean swing). I then turned the key off and back on to be sure everything was re-set. It went into closed loop mode just above idle, but when I drove the car it went right back to doing what it did before. No matter where I put the TPS, it behaves exactly the same. I'm guessing that the TPS circuit might be a resetting kind, like my Saturn, but I can't be sure, really, since I don't know how to read it through the comptuter.
Anyway, I've done just about everything I can think of, and have tested everything, but I cannot find this problem. The only thing I can think of left is to replace the TPS and/or the injectors. I doubt that the TPS would solve anything, and I strongly doubt that the injectors are at fault. If I unplug them, the car dies. I do not think that they are leaking or malfunctioning in any way. When I release the throttle, fuel is cut off fully, reliably, consistently.
Also, this last tank I allowed the CEL to stay on whenever it came on, and achieved an all-time low of 28 MPG. When the CEL comes on, the computer ignores the oxygen sensor. If I flick the key right away, though, it goes back to seeing the O2 sensor, and mileage is great (never lower than 35 MPG).
Thanks!
Anyway, pertaining to this thread, I am also getting the 1 and 16 codes. Until this year I didn't even know how to read the codes (and didn't care, really, since I never had any major problems), but now that I am getting a CEL repeatedly, I have found out how to read the codes.
For many years now, if I were to jump right onto the freeway with a cold engine, the CEL would come on. Flick the key, and it goes out. No more worries at all at any time. Warm the car up amply, and the CEL won't even come on. I have no idea what it was setting for because I never paid attention.
Now two summers ago it started setting codes all the time, and I figured out what they were (1 and 16), and so I bought a ton of fuel injector cleaner and ran it through the system. I also disabled one of the injectors so that the other would do all of the work, and all of the cleaner would be forced through it. After repeatedly doing this, the CEL stayed off until just recently. Now it's the same codes again.
I decided to hook a digital meter to the O2 sensor to have a look. This is what happens: at idle voltage holds in the 80s. Seems normal. Keep the mixture around stoichiometric for a smooth idle, and the O2 sensor can cool down, so it's best to ignore it. Then while cruising and driving, voltage swings high and low repeatedly, which seems normal for driving. However, when coasting down a hill, but maintaining speed, with the throttle almost all the way closed, mixture reading climbs to idle reading-- .88 volts or so. If the voltage stays at this high steady reading for over 10 seconds, the CEL sets. Likely in a modern car it would set a 'O2 sensor high voltage' code, or 'rich'.
Well I read online that the injector O rings can leak, and so I thought that this might be causing the mixture to go rich. However, if I completely let off the throttle while coasting, fuel cuts out completely, and the O2 sensor voltage drops to 0. That said, I doubt that the injectors are leaking in any way, as cutting them off would not stop a leak past the O ring on the side of the injector, where fuel pressure is still present. Also, fuel mixture at all other conditions is fine, and the car does not lope at idle. It idles like a brand new engine.
Fuel pressure is fine. I tested it. It falls within range, and holds residual overnight, indicating no leaks.
I tested the TPS and MAP sensors for basic functionality. The TPS voltage/resistance changes smoothly, and the MAP sensor voltages match closely to recommended voltage/vacuum readings.
I guessed then, since everything seems to be fine, that perhaps the TPS might still be inaccurate near the closed throttle position, since this is the area used most often. ....So I adjusted it. I tried advancing it. I was actually able to just get the system into closed-loop (up-down-up-down) mode at idle, and I backed it off until it just went into open-loop mode (no rich-lean swing). I then turned the key off and back on to be sure everything was re-set. It went into closed loop mode just above idle, but when I drove the car it went right back to doing what it did before. No matter where I put the TPS, it behaves exactly the same. I'm guessing that the TPS circuit might be a resetting kind, like my Saturn, but I can't be sure, really, since I don't know how to read it through the comptuter.
Anyway, I've done just about everything I can think of, and have tested everything, but I cannot find this problem. The only thing I can think of left is to replace the TPS and/or the injectors. I doubt that the TPS would solve anything, and I strongly doubt that the injectors are at fault. If I unplug them, the car dies. I do not think that they are leaking or malfunctioning in any way. When I release the throttle, fuel is cut off fully, reliably, consistently.
Also, this last tank I allowed the CEL to stay on whenever it came on, and achieved an all-time low of 28 MPG. When the CEL comes on, the computer ignores the oxygen sensor. If I flick the key right away, though, it goes back to seeing the O2 sensor, and mileage is great (never lower than 35 MPG).
Thanks!
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Well thanks for the help, or lack-of My Chilton's manual is practically useless. ....But I think that I found the problem on my own. The TPS is in fact bad. For some reason every time in the past I tested it, resistance changed smoothly, but today I noticed that the voltage was jumping around, so I took it off to confirm, and with an anolog mechanical meter, the best kind for this test, I noted forward movement of the needle, and then it jumped around, and even dropped all the way down, and backward and forward, and then smooth forward motion, so the low end, which is the most used end, is definitely worn out. Noone sells this TPS locally, so I ordered one on eBay. For the time being I have drilled a hole in the original and am going to inject some WD40 and hope that it improves matters until the new TPS comes in the mail.
It is obviously fooling the computer into thinking that the car is at idle, and is telling it to run the idle mixture, which then trips the CEL because the oxygen sensor reading is rich, and not fluctuating.
I will know for sure when I receive the new TPS, and I will report what I find.
It is obviously fooling the computer into thinking that the car is at idle, and is telling it to run the idle mixture, which then trips the CEL because the oxygen sensor reading is rich, and not fluctuating.
I will know for sure when I receive the new TPS, and I will report what I find.
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I started my own thread in the electrical section. The new TPS improved part-throttle acceleration and reduced the CEL problem, but it has not eliminated it. I have the TPS set at .5 volts, which I have read repeatedly is the correct setting at idle, though I have tried .45, and even other voltages as low as .2 and as high as .8, all of which created interesting responses, but none of which corrected the problem.
....So there definitely still seems to be a problem ...to which noone has an answer.
....So there definitely still seems to be a problem ...to which noone has an answer.
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