1995 civic EX Multiple issues

kody514

New Member
Got this car in a trade and it has me stumped. It was sitting for awhile and the tank was very dirty. 5th fuel filter on it within the last 10k miles. But after this last filter swap it has started running horribly. it struggles to get up to any more than 60 mph it will take 1/4 mile to get to 60 it is getting way to much fuel. and it bogs way down wont build any rpm. injectors are clean it sounds as if its missing but all cylinders check out good. it will literally roll coal. I was thinking about getting a fuel pressure regulator but instead of patching the problem I wanted to actually fix the cause of it.

it is a d16z6

what are some things that could cause it to get to much fuel? As if injectors are stuck open it is literally getting 10-12 miles to the gallon and is running at about half the power it was.
 

daperez13

Respected
Check fuel pressure, injectors, spark. Check all your vacuum hoses. Perform a compression test. Remove your catalytic converter and make sure it's not damaged.

Any CEL's?
 

kody514

New Member
Check fuel pressure, injectors, spark. Check all your vacuum hoses. Perform a compression test. Remove your catalytic converter andmake sure it's not damaged.

Any CEL's?
All injectors are good im running straight pipe since cat and resonater got clogged compression vaccume lines are good had a small leak but fixed it. test came out fine ran it today all cylinders were within 5 of eachother my check engine light is currently on due to o2 sensor broken. But o2 sensor was fine but it started running super rich all of a sudden I unplugged it then accidently slammed my hood onto the plug. Im not sure if i tested it right but i went to test map sensor with a multimeter and it didnt pick up any power coming to the map sensor plug. Timing is good. New distributer cap plugs and plug wires air filter fuel filter. The car sat for awhile so tank has rust been running super and seafoam swapping fuel filters every 1k miles. But it recently overheated before it started running rich. Swapped radiator and thermostat still overheating. Water pump valve cover gasket timing belt and tensioner should be here tomorrow. Next week i will pick up a o2 sensor and try and fix why my map sensor isnt getting any power
 


daperez13

Respected
That could be your problem! When an O2 goes bad, it affects air/fuel ratios and with time, it damages components (catalytic converters specially), your efficiency goes out the window. Also, if you've ever leaned-out the car, like running out of fuel, that could damage your cat and injectors.

Definitely check fuel pressure - your fuel pump might be out with all that pollution in the tank (it stresses out). Pull the pump out and clean your fuel tank as best as possible. If the fuel pump is still good, change out the fuel pump filter and fuel filter. Don't use any more additives.

You will have to check timing once you have resolved any issues that can affect timing. Since the ECU is not reading an O2, it's trying to compensate based on pre-programmed tables.

What was the compression readings? You mentioned they were within 5...I'll assume you meant PSI. What was the total PSI reading?

When a car overheats, it affects timing. When timing is off, a vehicle can overheat. Definitely change your water pump (preferably with an OEM or another quality unit), thermostat and check your radiator and hoses for leaks. If your compression is truly within specs, you should perform a leak-down test - your head gasket could be blown. If it was severe enough, you could have bent valves and/or a warped head, even a crack in the head or block.
 

kody514

New Member
I unhooked the o2 and cut the pipes after it started running too rich the injectors and valves are good psi was 192 192 194 197 all hoses are new i went ahead and replaced them when i replaced the radiator and thermostat they are all tight. Timing is good. Im hoping the o2 sensor helps the tank is about cleaned out now the motor itself is fine im just trying to sort out why it is running so rich. Its to the point you can smell it out the exhaust and it causes it to sound like and act as if it is flooding out. It doesnt die just wont accelerate and ferls like it has half the power it use to.
 

daperez13

Respected
IAT (Air Idle Temperature), bad O2, vacuum. One or more injectors could be stuck open. Valve lash and timing.

Not sure if you answered this already but do you have any CEL's other than the O2?
 

kody514

New Member
Tested all the injectors they are working flawlessly. I think its some sensor telling it to keep sending fuel so o2 or map sensor. Nope o2 sensor is the only thing making a cel. Which is another reason im struggling to find the problem. Most of the sensors if failing or not working properly would throw a cel
 

kody514

New Member
swapped the o2 sensor and it has alot more bottom end power but its still struggling to get any acceleration in 4th or 5th. 0-60 it is alot quicker.
 

HeX

Authoritah, respected.
Staff member
Registered VIP
5+ Year Member
10+ Year Member
That sounds like a positive result for a faulty O2 sensor. Make sure to get an NTK O2 and no other brand. Hondas are very particular in this regard.
 

kody514

New Member
no burnt fuses must have a short somewhere in the harness :what:replaced tps not sure if its my ecu adjusting fuel maps or what but it is running better on top end now. still on the rich side but not anything like it was. roughly how long does it take the ecu to adjust fuel map? cel came on after swapping tps so disconnecting the battery cables for 30 minutes and will go take it for another 20 miles or so.
 

daperez13

Respected
Whenever you disconnect the battery, you need to perform particular drive cycles to get all your applicable monitors ready. Lookup 'set readiness monitors' to get an idea on how to perform that. The ECU applies pre-programmed air/fuel mix tables until it reads certain sensors, until then, it will be running a bit on the rich side.
 


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