...On a '98 Integra LS. This is my first post here, so please let me know if I'm posting this in the wrong area, breaking rules, etc.

I'm a little out of my element here. I'm your typical knuckle-dragging neanderthal who'd be a lot happier rebuilding a Holley, installing a shift kit or adjusting rocker arms. I barely comprehend anything with less than eight spark plugs, and if it doesn't have pushrods it must be magic. Clearly I need some help.


This is a B18B1, if it matters...

The symptoms:

Six OBD II codes. I don't have them in front of me now but I remember what they are:

Misfire on Cyl 1
Misfire on Cyl 2
Misfire on Cyl 3
Misfire on Cyl 4
Mutiple Misfires
Mutiple Misfires

It idles rough, takes a few seconds to start, and of course it runs like complete ***. Very erratic. Sometimes it pulls ok when gradually moving to half throttle, but usually it bogs under load. Entering an intersection from a stop is not for the faint of heart.

This problem seems to have started after some cooling system issues. It's a young lady's car, and not to be stereotypical - I know there are plenty of women out there who watch and understand the gauges and lights on their dash, but I have reason to believe she has no interest in that sort of thing. It's entirely possible the car overheated, a lot, so I did a compression check. Here are the results. (Dry and cold)

Cyl 1 - 148 PSI
Cyl 2 - 160 PSI
Cyl 3 - 160 PSI
Cyl 4 - 165 PSI

If I remember right, these numbers, while not perfect, are not that bad either, right? Minimum is 135, nominal is 199 I think. And remember this is a dry test. I did a crude leakdown test by leaving the gauge connected and pressurized on each cylinder for a few minutes, and I saw no appreciable amount of pressure loss. I then put a little oil in the cylinders and the pressure shot up to about 210 PSI, but that's not really a valid number because I probably put more oil in there than I should have.

There is no observable oil in the coolant.
No observable coolant in the oil.
No steam or smell of coolant from the tailpipe.

...although I did see soot on the tailpipe, so I suspected the catalytic converter might be plugged. I disconnected it, no change.

Checked for vacuum leaks, none found.

I measured the fuel pressure and it was right on spec. (I don't remember exactly what that number was right now though, and I only checked it at idle.)

Changed the fuel filter.

Changed the spark plugs - They were pretty badly out of gap. The new plugs helped some but I don't think they were related to the main problem. The new plugs have a good tan color to them now and they all look the same.

Did not change the plug wires, but they Ohm'ed out ok and I just can't see all four of those being bad at once.

Changed the ignitor, distributor cap, rotor and coil. Admittedly these were junk yard parts, but by the time I got to the point where I'm just "throwing parts at it," which is a place I hate to be, I really didn't want to waste a lot of money.

Swapped the MAP sensor with a used part, no change.

Checked the TPS with Ohmmeter, no glitches, but replaced it anyway with a tested used part. No effect.

Swapped the O2 sensor with a known good used part, no change.

Having run out of other ideas, I decided to rule out bad gas, so I put $25 worth of 93 octane in it. No change there either.


...I know it's entirely possible that any one of the parts I replaced, such as the MAP sensor, could still be bad. But I'm kind of dubious about that because I'm only getting the misfire codes, and misbehaving sensors like TPS, MAP and O2 I would expect to throw their own codes. I'd also like to find out how to test those before I swap anything out a second time. I was able to test some things, but on the MAP sensor for instance I couldn't find anything helpful.

I've got to be missing something here. Crank sensor? IAC?

Thanks in advance for any help you can provide.

 

Sounds like you got everything obvious, one thing I do know is that the ecu in hondas isn't smart enough to figure out what cylinder the misfire is coming from if it's not all of them, so it will tell you they are all misfiring usually. Another piece of advice I can offer is go on www.hondahookup.com and register a free account, once you do they have free downloads of the pdf versions of all the factory Honda/Acura service manuals and it will give you a detailed troubleshooting procedure. Also just so you know for a knuckle dragging neanderthal you sound a hell of a lot smarter than 95% of the people who post on here.

 

check the valve adjustment. possible to have the same problem as the b20 crvs. the exhaust valve receed into the head causing misfire codes.

 

As mentioned already, 1 cylinder misfiring can cause all those codes. I had an odyssey at work doing the same thing and it turned out to be 1 bad coil pack (coil on plug).

The 2 other main causes I've read about are valve problems or a clogged injector.

 

i'm with you....check the valve lash....see if any of the exhaust valves are tight...better yet check and adjust all to spec if possible...

 

Thanks for all the suggestions, guys. I fixed it yesterday with a junk yard distributor. (from a '95 Odyssey of all things...)

I'm glad it's over with, I've never been so close to giving up on a car. The most frustrating thing about it is I thought I'd already ruled out the distributor.

Thanks again!