I will repost info from other thread/different site.


Ok heres the backstory and issue, thanks for checking in.

00 LS, 190k miles

The idle has been rough for a little while now, but moreso after I got a timing belt/water pump change last week. I got it back and it runs better, but the idle has gotten worse over the past week. I did the usual clean IACV, replaced plugs, and was checking the cap and rotor, well the rotor screw backed out, and the rotor smashed into the lower left distro cap stud (cyl#1). so The screw was laying there, rotor bent, and cap tore up. I figured this was for sure my problem! I replaced cap/rotor/screw, cleaned the white dust crap, and it fired up a little better, but the miss is still there.

I also replaced the plug wires, and put in a new ignition coil this morning, with minor improvements. Any ideas?

 

check your timing, make sure everything lines up, also if it is then move ur dizzy back and forth to see if that helps

 

Im going to check mechanical timing tomorrow, kinda running out of ideas. I am also going to do a compression test to rule that out also. Im throwing an o2 code, got a new one at home and will throw that in tomorrow too, Im pretty sure that wont fix my misfire though.

 

I'd agree with the timing, especially since you did your timing belt. Another thing, that I dont know if you've checked is the gapping on the plugs, maybe it could be something that simple, but worth a try.

 

plugs gapped fine, timing is okay.

It doesnt smoke or anything, I started to do a compression test, but the bit that screws into the spark plug hole got stuck and I had to superglue a spark plug to get the piece out. That took an hour so I had to put it back together and get back inside to work.

It still seems the same, but the idle is a little better and the exhaust sounds a little bit better than a few days ago.

Also, I read somewhere that to check for bad valves you can hold a piece of paper by the exhaust when the car is running, and if the paper gets sucked in and blown out then a valve(s) are bad. Any truth to that test?

 

this is the test Im talking about, if it sucks in then it could be valves or valves not seatin properly.. Can anyone confirm/deny this works on a b18b?

 

alright just did compression test

#1 - 155psi
#2 - 152psi
#3 -154psi
#4 - 150 psi


Even though they seem low, there isnt really a variance so I will assume these numbers are okay. Test was done half warmed up, dry, and WOT while cranking for 8 seconds per cylinder.

All comments welcome.

 

pull each plug wire to see what cylinder is misfiring, check to see if they all have spark, if so check to see if you have a faulty injector. thats what i would do.