i just finished putting a jdm b18c1 into my cx. it ran fine for about on hour the first day i had it out driving, then it started to stumple when i accelerated. it only has problems when the car is warmed up, not when i first start driving it. the idle moves around between 1000 and 500 rpms. when i rev it kind of hard, it sounds like it just cuts out and will stall. when i'm driving it, it bucks in low rpms if i get on the throttle too much, but not after around 4500 rpms. i already replaced wires, plugs, rotor, cap, and fuel filter. any ideas would be helpful before i drop some money on a new distributor because thats the only thing else i can think of. thanks.

 

oops, guess i didnt search good before cause i found some stuff. but if anyone has had this problem before and knows how to fix it, please share. thanks.

 

Did you figure out what the problem was? I'm having a similar issue with my Integra, and I think it's affecting overall performance, even at upper RPMs.

 

I have a problem close to that...i havent fixed it yet but i was told that the problem could be in the intake manifold, either a bad manifold or dirty manifold.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by alfaaay &raquo;</TD></TR><TR><TD CLASS="quote">Did you figure out what the problem was? I'm having a similar issue with my Integra, and I think it's affecting overall performance, even at upper RPMs.</TD></TR></TABLE>

no i still can't figure it out. i thought it might be the o2 sensor because when its running open loop the car runs fine, but after it warms up, the car starts running bad which might be because the o2 sensor is sending wrong signals. so i bought a new one and it didn't help. but i might of wired it wrong because it was one of those universal ones. but it doesn't throw a cel, so i still have no idea.

 

bump, anyone find a solution to this?

 

stumbling on acceleration?

my first guess would be that the primary sensor is on its way out, or possibly the cat is clogged... good luck

edit: instead of spending money on all these parts, find someone with a civic that can let you borrow parts just to check and see if the problem goes away

 

inspect the throttle position sensor (TPS) I had the same problem with same car, same motor. I slighty damaged the TPS upon install car ran fine for a bit then started to stumble on ACC. I damaged the TPS on the fuel filter, slightly cracked it. Swapped out the TPS sensor ran the test to position it correctly. Ran perfect after that.

Of course theres all the normal stuffs
timing set correctly
no CELs
good plugs and wires (i always use honda OEM parts the best to use IMO)
valves not to tight or carbon filled (you said the car ran cool at first start up so prolly not that)

well good luck