P303 on a 96 accord, I’m going INSANE!!!

[Bret]

I made a new thread because i think i hi-jacked somebody’s thread, and u/FATDOG (pete) sorry about that 🙁

1996 Accord
2.2L F22B2 (non-vtec)
5 spd manual
all stock

A little bit of back info

Did a head gasket after the radiator went and the SO overheated it driving 30 miles home
got it up and running, but rough

Replaced:
Secondary O2 sensor- was bad, and throwing a code
ECT sensor on the tstat housing- fans arnt kicking on but thats another day kind of problem because i havent had it up hot enough to kick it on yet to fully test
ignition wiring harness- PO had added a hack job alarm, and the wiring drove me insane looking at it.
Thermostat

All new gaskets went in with a Felpro kit after having the head skimmed and crack checked.

I’ve tested for spark, and can hear the injectors clicking, i cleaned them while the head was off by making a hose adapter with hose clamps and used carb cleaner while i applied voltage to clear them

Valve adjustment is on point (i can use shims, I’m a machinist by trade)

I do have an Innova 3040C scanner, so heres my freeze frame
Fuel sys1- CL
Fuel sys2- NA
Calc load- 37.0
ECT (F)- 188.6
STFT B1 (%)- 12.5
LTLF B1(%)- 0.0
MAP(inFg)- 11.2
Eng. RPM- 694
IAT (F)- 105.8
TPS- 9.4

This reading was taken at operating temp, as the code wasen’t thrown until then.

Also did a compression test, WOT just after this code to be sure
***im pretty sure my compression is low across the board, think they’re supposed to be around 150-170

Dry/Wet
CL1- 120/130
CL2- 118/130
CL3- 120/132
CL4- 120/135

Sorry about this wall of text, wanted to give as much info as possible.
any and all help is appreciated.

Topic

[chad]

I am not very knowledgeable but, did you take a look at the EGR valve> Check for carbon build up holding the valve open?

Did you check your mass air flow sensor> Do Not Touch the metal on the MAF, Use a carburetor cleaner and spray wires and air dry. Removes oxidation on wires that hinder’s accuracy.

[Rick]

If I get a break tomorrow I’ll ask one of our better techs to see what they think.

Personally I have to see something, hear it, touch it, taste it before I offer advice.

[Frank Gonzalez]

P0303 is a misfire in #3 cylinder. Check for a bad plug, wire or cap. With a test light and the engine running, check injector electrical connection, the light should be flashing. Check injector resistance and make sure it’s within values. Make sure its not plugged up. Check for vacuum leaks, bad head gasket or cracked head.

[Its me]

With low compression like that across the board I would highly suggest you re-check the timing (belt timing)… Your cam(s)may be slightly off where they should be and it would cause a condition like this.

Also FWIW the IAT looks a bit high (unless you are in a warm climate for October) but that shouldn’t cause the issue you are talking about.. just looks a little off.. 🙂

Karl

[Bret]

@ toyotakarl- i will recheck the timing tonight and referance my Hanes manual if it needs adjusting. but wouldn’t the timing being off a little throw misfires across the board? also, I live in FL, so I think its safe to say it’s a little warmer here than elsewhere lol

@cave1376- I know for fact the cap, wires and plugs are good, but will run a test light over the injectors tonight as well, before i pull it apart to check timing.
the vacuum leaks have also been driving me crazy because i cant seem to find a diagram for my routing and the one under the hood is gone.

@pitt- much appreciated

@premo3d- i know for a fact the EGR is clean, and i have new gaskets on it, but ill spray down the MAF, never hurt to clean things up a bit. i also went though and cleaned the egr ports on the intake when i did the head gasket.

all your guy’s time and help is appreciated.

[Frank Gonzalez]

I forgot to ask, how are the spark plugs? Look online for your cars vacuum diagram. Make sure the code for the diagram matches your car. The same car can have multiple vacuum diagrams. As for vacuum leaks, check around the #3 cylinder intake manifold gasket.

[Bret]

UPDATE-
ran a test light through the injectors, and all are firing, but will be physically pulling them to check resistance tonight, just to be sure about them 100%

@ cave1376- the spark plugs look good, they’re new, and haven’t even seen load yet, they are gapped correctly (NGK always does me proud)
whats the best way to leak test a gasket like that? the carb cleaner trick ECTG used for vacuum lines in his video? i was missing a line on the right side, the one that runs back to the fuel regulator, but ill be pulling codes again tonight after resetting and will up date tomorrow.

[EricTheCarGuy]

I would table the fuel injector theory. Hondas very rarely have issues with fuel delivery, mostly spark issues. You say you adjusted the valves and also removed the cylinder head. I think it’s more than likely something you inadvertently did that’s causing the issue. As suggested, go back and check the timing marks as well as the belt tension to make sure they’re correct. I’d also recommend rechecking the valve clearance to make sure it’s correct. It takes a seasoned, experienced tech to do that correctly. It’s not difficult to get it wrong. Before you go chasing down something electrical, rule out any mechanical issues first. More info here.

http://www.ericthecarguy.com/faq/solving-automotive-performance-issues

As to your theory that if you had the timing off that it would show misfires on all cylinders, this is not correct in my experience. Especially with the older models like yours, misfire detection had much to be desired. The computers just weren’t fast enough to be accurate. Misfires are detected by measuring crankshaft acceleration after an ignition event BTW.

Thanks for starting your own thread on this and please keep us updated.

[Bret]

I’ll be pulling the valve cover tonight and checking timing. after i get that situated, ill double check the valve clearance.
assuming the timing is off by a tooth or so on the cam marks, do i simply
1.loosen the adjuster
2.remove the belt
3.rotate the cam shaft
4.replace belt
5.tighten the adjuster
6.rotate the pully counterclockwise ~3 teeth to add tension?

also, ill be reading into the posted link here and give an update tomorrow as to what i find.

thank you all again for your continued help, advice, experience, and more importantly you time

[Bret]

https://www.dropbox.com/sc/grq5p2pxs4cyhpm/AADngBptC0XTfQRzSK5aaVTEa

not sure if those pic will show, hopefully the link will
there shots of confirmed timing (cam anyways)
i double checked ignition with a timing light i got today, all was good.

Retested my primary 02 sensor as bad, found a Denso in the scrap yard that luckily tested good.
replaced it, and the fuel filter, which was a PITA! for sure.

re checked timing and confirmed with a timing light for ignition timing, as well as checking valve clearance.

still had a P303 pop up

because i have a reader with freeze frame here are the numbers, the first one is when it came up to op temp, the second is after i cleared it and restarted the engine.

Fule Sys 1- CL
Calc Load- 32.9
ECT (F)- 181.4
STFT B1 (%)- 22.7
LTFT B! (%)- 0
MAP- 9.7
RPM- 683
SPD- 0
IAT (F)- 102.2
TPS(%)- 9.4

After restarting the engine

Fule Sys 1- CL
Calc Load- 32.7
ECT (F)- 181.4
STFT B1 (%)- 18.8
LTFT B! (%)- 0
MAP- 10.0
RPM- 679
SPD- 0
IAT (F)- 116.6
TPS(%)- 9.4

as usual, any help is appreciated, always dirty-
Bret lol

[Bret]

Finally, after much time, effort, beer, and head scratching, i went back to the basics…
pulled the injector electrical connectors to do a powerbalance to find the dead cyl.
knew spark was good, and all sensors i had checked were good. so i moved the injectors around.

…my misfire moved with it.
so 60$ and a half hour later, had it up, now its running beautifully, but the fans still aren’t kicking on. the AC I’m not too worried about because its never used. but the cooling fan doesn’t come on either, at least not at 230 degrees. i ran with my scanner plugged in to watch it work,

any ideas buy?
as usual, thanks for any and all help and your time.

[My Nameis]

So it was a bad injector? Didn’t you say you heard all of them firing up? So it was more so clogged up I’m guessing.

Does the fan kick on with direct 12v to it? If so the temperature sensor that controls it could be bad. If no 12v present trace that back to a bad wire

[Bret]

It must’ve been clogged. i know i cleaned them while doing the head but thats the only thing i can think. they all had good resistance and an audible pulse (via the long screwdriver & noid light)

as far as the fans go. if hooked directly to the battery, they both run fine,i can also jump the connectors on the tstat housing and the front fitting that’s identical to that, and one runs while ones jumped, and both run while the others jumped.

Iv’e bled the cooling system already but will be pulling the tstat again to make sure installation is correct (with the hole up top) as I’ve heard incorrect installation can cause the same problem, as the ETC is reading air as well as coolant. other than that im prone to believe they’re bad sensors.

is this the logical, correct path to follow here?

[My Nameis]

Sounds like a plan. Question though, does the upper radiator hose feel warm to the touch when the car is up to temp? If not that usually indicates tstat isn’t opening

Sent from my iPhone using Tapatalk

[Bret]

it does feel warm to the touch when up to temp.
i’ll go as planned tonight assuming i can get some time from this rain we’ve had lately, and ill update tomorrow.

thanks again all

[Author]

Replies