Schmitey

I have a 96 Accord EX manual and its been running like a champ getting 32 mpg highway and 25+ in this hot summer one hundred plus degree weather running AC. Recently on the drive home from work after the car had been baking in the sun all day I flipped a CEL and checked the code/s when I got home. Bridge the blue connector and get four long flashes and five short...look in the Haynes manual and there's no code 45 listed. I turned the ignition on and off and watched the code probably a dozen times as it repeated itself.

I checked my Helms manual and there is no code 45 for this vehicle that I'm aware of... In desperation I started pulling spark plugs and just making sure everything was ok. On one cylinder (three I think it was) I discovered that the O-Ring that seals the valve cover around the spark plug tube was leaking slowly and I had some oil accumulated. Cleaned it all out, unplugged battery, and went a few more days code free.

A few days later I got another CEL and this time it was a code 71 I think (7? something for misfire). I went back to the oil filled spark plug and discovered it was a little loose and figured I wasn't getting full compression. Cleared the code and went a few more days code free.

Most recently I got yet another code 45 on a hot hot day. Cleared it and its gone a couple days now without flipping a CEL again.

Last fillup my gas mileage dipped a little bit, but the problem has only lasted half a tank so it doesn't mean a lot. I have noticed that it feels sluggish and like its missing sometimes on acceleration...like its running out of gas. I'm totally out of ideas any and all help would be appreciated.

dglassmyer

Refer to this post. Looks like a lean fuel issue.

https://honda-tech.com/forums/honda-accord-1990-2002-2/check-engine-light-codes-cel-diagnostic-trouble-codes-dtc-malfunction-indicator-light-mil-1490107/

Schmitey

So I get that OBD-II is an industry standard...but why wouldn't code 45 be listed in my manuals then? Should I accept this lean fuel (which it IS running as such) diagnosis or question whether the ECM is going out?

I've got a fuel filter already and have been meaning to do it again. Its such a pain in the butt...changed it about 50k ago when I first bought the car.

dglassmyer

I think the issue may be that your manual is listing the diagnostic trouble codes and not including the check engine light codes as reference.
So where as you are seeing a CEL of a code 45, the DTC will be something different like P01300 or whatever the lean fuel DTC was.
And yes it almost seems honda felt like giving people headaches with the location of the fuel filters in our cars.

Schmitey

This weekend I changed the fuel filter after buying a set of 3/8 crowsfeet. The filter definitely needed changing: blackish gas flowing from inlet side and obvious resistance when blowing through old filter. The car appeared to immediately drive/accelerate better but roughly 75 miles later on yet another hot summer day (115 degree heat index) I got a code 45.

I don't know where to start as this code isn't even listed in the Helms...but the fuel pressure regulator seems like the next best culprit. Its like $56 new for the regulator and used ECM is like $65. What would you guys do?

bdmlilburn

before you replace the ecu take it out(after pulling the negative on the battery and remove both plates on each sides with a philips head. check for burnt areas on each side.there are also ways of testing the fpr though cant remember them off the top of my head. due to the blackish gas on the inlet of your fuel filter i would run a can of seafoam through the gas tank before you change it again.

Schmitey

Just found out a family member has a fuel pressure tester/guage and more importantly a fitting that should apparently work so I'll try to test the regulator. Any ideas how long these things last and if a junkyard part would be a bad idea?

Schmitey

Bump

Schmitey

Been scouring the forum and even found a Honda service bulletin on the P0171 code... Looks like it could be a bad O2 sensor or clogged EGR.

I'll clean my EGR ports as its been a while since I've done that. I can not for the life of me find a fuel pressure tester for this darn thing short of spending like $200 for an entire set. What kind of gauge/tester are you guys using and what does it thread on to? Preferably a DIY option as I have a gauge already there just aren't many metric fittings/bolts floating around.

Roader

O'Reilly (Checker) loans out fuel pressure testers for free, with a hefty deposit. It comes with several different fittings. The one that worked connects to the top fuel filter line.

Schmitey

Hit up the O'Reilly's here in Lincoln, NE and they loan out everything BUT fuel pressure testers...GRR!

I cleaned the EGR ports and 2 and 3 were almost fouled over but not near as bad as it was when I first got the car a few years ago. Its been two days and so far haven't gotten any codes. It doesn't sputter/misfire at 2300 RPM anymore and seems to have more power when warm so we'll see. Cleaned my K&N and ran some HEAT w/fuel injector cleaner as well.

Schmitey

Well cleaning the EGR ports didn't fix the problem and the CEL came back. I replaced the fuel pressure regulator as well and it didn't go away.

Finally I got a nice Actron 9580 scanner and noticed that my throttle position sensor may be going bad. It shows 9% throttle at idle and 90% when wide open. I'm hoping to test it with a friend's voltmeter tomorrow. Has anyone experienced anything similar? I've never heard of a TPS sensor sending false readings they usually just fail and flip a CEL.

MAD_MIKE

I'm not following what you are saying. If when opening the throttle the TPS reads a consistent linear change in voltage it is fine. You are not looking for hard numbers, just that the TPS is working without any dead spots or inconsistent voltage readings. You don't want your idle to read 0% as that would mean a fully closed throttle, IOTW, no air would be allowed into the engine. Don't expect to find '0'V or '5'V with the meter on the output of the TPS while its mounted to the TB. You will most likely see a .5V-4.5V reading as you sweep from idle to WOT setting on the TB.

If you still getting a P0171 lean code, check for intake and exhaust leaks.

Schmitey

Engine off it still reads 9% throttle, which leads me to think the TPS is either faulty or is out of adjustment (I know the screw holes give it some play).

I'll check on intake leaks, I just don't have time to tear things apart/troubleshoot. I commute and drive a lot, its my only vehicle, and its often dark when I get home.

This morning I got a PO131 I think it was...bank 2 oxygen sensor low voltage. It only came on once and looking at realtime data it looks fine. I really don't know what to think but I'm getting tired of throwing money and gas at it...

bdmlilburn

have you pulled the o2 sensor to see if its burnt? if it is make sure your cat is in good shape also. how does it idle when cold and hot? does it hesitate in a certain rpm range?

Schmitey

At 2200rpm low throttle I can almost always get it to hesitate/miss. Went on 500 mile roadtrip in cold weather and at times was wide open and it would just bog down with no power. I also could force some wicked backfires around the 2200 rpm range low throttle in fifth gear...you'd floor it and most times it would come back to life and stop missing. Never got a CEL that trip...

Yesterday after poking around on the forums I cleaned out the Idle Air Control Valve and the screen was pretty well clogged up with carbon. I cleaned it up and even my wife commented that it warms up in a fraction of the time, runs better when cold, and doesn't hesitate anymore. It's too early to say just yet but I'm hoping that fixed the problem.

Schmitey

Still chasing this damn code...voltage readouts for the oxygen sensors are precisely where they should be and responsive when watching real time data on my scanner, though its been a while since I've tested it.

I disconnected the resonator long ago and capped the vaccuum lines...I'm starting to wonder if perhaps I have a vacuum leak and its throwing off the Fuel Injection Air Control Solenoid/airflow to injectors. Not really sure how that whole system works and if it would give me these symptoms.

I do have exhaust leaks but don't believe its before the cat. If my cat converter is bad/rusted out would it cause this leaning out issue?

I developed a fairly severe oil leak (2-3 qts every 5k miles) and have replaced the valve cover gasket (also adjusted valve lash), distributor O-ring, and VTEC solenoid gasket/filter (expensive hard to find little bugger!). It slowed the leak but didn't realize at the time there was a second gasket between the solenoid and pressure switch that I think has since started leaking since I took it apart. Also replaced the oil pan gasket.

I've had the fuel rail off a couple times cleaning the EGR passages and have never replaced the injector o-rings...could I have a leaky or stuck/laggy injector? I've checked the fuel pressure but that was only at idle (R-12 connector my dad had lying around fits onto the fuel rail connector and we stuck an old AC gauge on it). I'm hesitant to drop the tank and replace the pump/screen.

I'm at my wits end and don't know where to even start with this damn car...got like 196k miles on it now and of course a new set of tires.

holmesnmanny

If it was me, I would check the fuel pressure first, assuming you're using a new denso oxygen sensor. If that checks out, I would buy a set of rebuilt injectors.

holmesnmanny

Just for the hell of it I would check the resistor box at each terminal for correct ohms, and that it's getting 12v power.

MAD_MIKE

Yes.

If there is an air leak, be it intake or exhaust, the O2 sensor will register the dilution.
Being a OBDII system there are two O2 sensors, the primary(before catalyst) which is what measures/controls A/F and the secondary(after catalyst) which monitors the emissions systems functionality.
Just because an O2 sensor code has not been tripped does not mean that there is not an issue with the A/F ratio.
http://www.autoshop101.com/forms/h56.pdf

Have you had any emissions testing since this problem occured?
If so do you have the readout and if so can you post up what the numbers are? Preferably a 5 gas readout would be best.

If you are still wondering about the TPS there is no problem with it. ~9% is what .45V is. And that is normal for a closed throttle.

Since the stumble/lean misfire happens around 2000rpm I would still suspect the EGR system is not fully up to snuff. When you cleaned it did you verify that the EGR valve works correctly? Did you clean all the EGR ports, not just the intake runners but the main feed ports at the EGR valve?

Have you checked/replaced any part of the ignition system? Plugs, wires, cap, etc? If it's been a while I would pull the plugs and verify what they look like.

An easy way to check for exhaust leaks, and help clean out any gunk/carbon build up, would be to add Sea Foam to the intake tract. It will belch out white smoke from the exhaust, when it does this the smoke will also escape from any leaks in the exhaust system. Did this while chasing down an exhaust leak on a WRX and it worked perfectly. The leak was suspected in one spot but was hard to tell, and the leak was actually at a different joint in the system.

Schmitey

No we're not hippies here in Nebraska/Kansas where I'm from and don't have emissions testing...hell you'd have a hard time finding a mechanic who has the equipment.

I'll have to track down a vaccuum pump/gauge and check the EGR valve, I've cleaned it but not checked for leaks etc? I've cleaned the ports/runners before but never replaced the injector o-rings as I'm sure I should have...could that cause these symptoms if they were leaking ever so slightly?

Plugs, wires, cap/rotor all replaced as regular maintenance aka where the hell is my gas going! Last I checked the compression is good as new. Its been a while since I've run seafoam...I swear that stuff has like tripled in price!

My brother in law just bought a used snap-on scanner (mechanic was gotta get like $200 credit for it so he sold it private to him since he bought most of the cords and cartridges for it anyways) that I'm told it lets you isolate and override datastreams to troubleshoot bad sensors. Might be fun to play with anyways...

chris89

It'll throw a lean code in many instances on being running e85 which will yield less consumption ie lean. Otherwise I run 93 and it clears the code for good. It'll also do it if u have a nano crack or leak in the header anywhere between the 1st o2 so a new header may be in order.

GhostAccord

Anyone who runs E85 in a stock 96 Honda Accord is going to have more issues than just a code 45 on their hands.

These cars are not programmed or engineered to run E85. You will not see any benefit to running ethanol in any Accord that has not been engineered from the factory to run it or has been modified and properly tuned/reprogrammed electronically. In my opinion you would be better off running premium with no ethanol. I realize that is probably no longer an option in the US. As you have been forced by the administration/farmers to burn corn fuel in your cars.

Fitz Williams

iTrader: (1)

Some stations in SC are carrying ethanol free gas now. Usually just in one pump and at a premium price for 87 octane. I have not tried it.

MAD_MIKE