Freddybabs

This is for my daily driver so any help or tips from previous experiences is appreciated.

So here's the story.

1998 honda accord LX with the 2.3L. Car died on me a couple times which i fixed roadside - simple ignition problems (corroded dist cap etc). Recently was running like a top until it sputtered and died on me and had to limp it home (ran fine above 2000rpm) Now after diagnosing ive got good spark on all 4 cyls, good compression on all 4, good 12v at pump while cranking etc, good fuel delivery at the rail (no exact pressure cause no where to hook my pressure tester up to), no fuel filter to replace on these things apparently except screen filter, and air filter is ok.

So now itll barely start and run VERY rough if runs at all.. there's no tach movement while cranking, plugs were black as hell (were relatively new) and electronically timed so cant be adjusted (new distributor recently- was installed properly and double checked, and car was acting up before the swap) and the worst part of all this is NOT A SINGLE CODE shows up.. And the only thing ive found that was weird is there's no 5v to my map sensor but to my knowledge that would show a code for sure..

Only thing im leaning towards is faulty ecm pcm unit, crank sensor assy, or timing belt stretch or skip (although not sure that woudl cause this sudden and drastic change in running quality with solid compression all around).

Thanks for any help in advance

PsXtreme

You are correct in that the map sensor should have thrown a code and I have gotten my car to start with my map disconnected, but will run very rough. I have the 96 v6 version of your car and I had an issue which ended up being the coil. The car will run, but will surge and the tach goes nuts or doesnt move at all (stays on 0). The coil also burnt up the new rotor button and cap I just put on, so maybe thats your problem since you said your new plugs were black. If I were you I would go to the junk yard and get a coil and igniter and I bet that will fix the problem. Also, of cource you should probably clean those spark plugs with a wire wheel brush.

Freddybabs

I looked through all of the ignition system and i was skeptical about the spark it was putting out thats why i got a new distributor but it included igniters and coil and cap and rotor. Now there's always the issue that i might have a bad new part but the spark is now bright white blueish and cracks like no other. And also it's not a surging its like so rough running it shakes thewhole car violently which is why im scared to run it and keep checking things. could do internal damage depending on whats going on

PsXtreme

Thats what I was afraid of with my car because it was like my car was misfiring and thats not good for an engine. Anyways, the thing that has me concerned is you aren't getting 5v to the map sensor and I know from forgetting to plug my in a few times it runs rough as hell like you describe. So you should track down why 5v isnt going to the map sensor. You may be on to something with the faulty ECM, because thats where the 5v is suppose to come from and that might explain why you arent getting a code. You should get a wiring diagram and test to confirm on the computer side before buying another computer, since they are expensive. You may just have a short in the wire and that would be a much cheaper fix.

MAD_MIKE

Starting in '96 two sensors are now moved to the crank snout, crank and TDC sensors.

If they are dirty, faulty or a loose connection, there will be no signal to the PCM. IIRC this does not set a code.

Check for loose, damaged, corroded, wiring and connection. If the wiring/connection looks fine look for damage to teh lower timing belt cover, and look for leaks, spills, junk around the cover.

If you ran thorough a large puddle(or are missing the lower cover) the sensor(s) have have become soaked/dirty.
Pull off the crank pulley and remove the lower cover to inspect.

Freddybabs

So i got in a little deeper, after i found out i have no 5v from my ecu for the map circuit, and also found while disconnecting the map, tps, egr valve , and fuel pressure sensors, that i have continuity to body ground while probing the corresponding pins in the connectors to the ecu, while having each sensor disconnected one at a time. manual says to replace sensor that makes continuity go away. Problem is i got to the fuel tank pressure sensor and disconnected it and continuity went away shortly but came back intermittently. I did wiggle tests and looked near wiring for damaged connections or breaks etc. nothing. Could this be a main relay problem? i looked at it but thats about it.. looked fine.

and i did do quick tests on the crank sensor that i found in manual. readings seemed to be in range.

Thanks for any help