johnsy_20

hi everyone. icurrently own a 99 s2k and have been having trouble with the kangarooing, misfire, and uneven idle for a long time now.. i searched and searched and finally figured out it was a lambda sensor. So i took it to a garage and got the sensors both checked and turns out the lambda sensor that goes into the cat was screwed but never showed a cel... so i thought thank god il get a new sensor and my problems will be over.....so i went and bought a universal sensor and my mechanic wired it up for me..drove it a couple of mile and it threw a cel and started behaving again. my mechanic said it might be a faulty sensor so i brought it back and bought another one...brilliant i drove it home (about ten miles) and it was perfect, FINALLY!! then all of a sudden i feel this kangarooing and when i stopped the uneven idle was back but no CEL. i was really getting impatient at this stage so i decided to just go and buy a sensor off my honda garage maybe the universal ones are just no good. I collected my sensor and plugged it in when i got home....it lasted all of ten minutes..now iam really pissed and am down a good bit of money and cannot seem to find anyone who has any idea whats wrong, including the honda techs!!!!! will someone please shed some light for me the car has 93k miles and has just had valve guides on cylinder 4 replaced (two of them were worn and lost compression) about 1k miles ago. the compression is all fine i have no vaccuum leaks its well serviced and has no mods watsoever.

RedY2KS2k

Did the car have the problem before the valve guides were replaced, or not?

johnsy_20

yes had the problem before and ha it still wen i got it back

Kirpich

Was the onset of the symptoms gradual or sudden? That's a good clue to start. Check plugs. Do a search on Idle control valve cleanup, and do it. Do a search on MAP whack, and do it. These are common S2K weak points.

Does it do it in idle as well as driving under slight load?
Does ambient temperature/engine temp make a difference?

I'm stabbing in the dark here...

johnsy_20

iv done al that and the new lambda sensor cured everything...for about ten mins, as soon car got hot id say

Kirpich

Sometimes a cat's internals fall apart and keep the efficiency of the cat down. If you can, you can pull off the Catalyctic converter and look inside to see if it fell apart. That will cause lambda sensor readings to go whacky too.

johnsy_20

have had the cat off also but it looks to be fine!

pureS2000

this is just a guess - seems like it acts up when warmed up or when hot. maybe it's not the sensor but a wiring problem. something might be causing the wiring to heat up and shorting something (relay/bad ground/short/open in wiring or harness). i'd pull up wiring diagram and start checking continuity.

CKit

The O2 sensor in the cat won't affect your driving.
That is a secondary sensor and not used for adjusting AF ratios.

Clean your IAC, throttle body, and the hole for the MAP sensor.
Swap MAP sensor with a friend or purchase a new one.

If your idle is lumpy and you're misfiring, try new spark plugs at that mileage. Fuel injectors can fail over time as well. Rarely, a coil pack can go bad.

Enthralled

try new spark plugs first. they are cheap.