i did my 4000k oil change today and after my nx ran like a bag of S@*t. it has the sr20de motor in it.
under 2000 rpm it felt like it had lost a cylinder ie eratic ideling at 800rpm a lot of vibrations through the car at idle. it felt like it was almost going st stall a few times when i took my foot off the accelerator. at 2000 rpm it felt like the cylinder kicked back in. ie car jerked and shuddered. above 3000 rpm ran fairly average loss of power little vibration.
just checked oil level and was way over so dump it and re filled to correct limits. havn't tested since then
would too much oil possably do this.
i thought it may be the ignition so cleaned the direct ignition system(dizzy)(sorry used to working on carboretered engins)
checked all electrical connections they were good. although there was a lot of water in the spark plug holes. any further ideas i should i take it to a real mechanic. i was thinking of going to the ems self diagnostics next.

Get the water out of the sparkplug wells, if you haven't already. Dry everything off also and see how it runs.

Originally posted by pyro_15
although there was a lot of water in the spark plug holes. any further ideas i should i take it to a real mechanic. i was thinking of going to the ems self diagnostics next.

ACK! se-r sam is correct. Clean out the water. If it's seaping into the plug wires, then your getting no spark or very little spark.

Pull the wires and use a high pressure air hose if available. If not, get as much out of there as possible, pull the plugs, let it air dry, then re-install plugs, wires, etc.

did that and it runs the same. took it out for a spin around the block and when ever the motor goes under load ie acceleration it looses power and bogs down, surges a few times then is right again. any further comments.

Check in the cap and see if it got wet also. Inside.

Last time I washed the engine I also had water on the spark-plug wells. Naturally, I assumed that there was no way water could have gone in there and did not check.

Now comes the interesting part:

I drove for very short periods of time (3-15 minutes) for the next 4 days and did not have ANY problem at all!!!

On the 5th day, I drove for maybe 20 minutes with still no problem. parked and picked the car againa fter maybe 30 minutes, before it had time to cool-off. 3-5 minutes of riding and I had this unbelievable misfiring/gurgling/brrrrrrrraaaaaaappppp sound when stepping on it. The idle was fine, it was just from low to mid loads that this happened and it clreared up at WOT and above 5000rpm.

Checked it, found the water, removed as much as I could with fabric "tampons", still no go!. Did it twice more during the next day, run the car until hot, let it dry with the spark plug connectors off.

Everything was fine after that.

Postulation on what was happening:

There was maybe 1 cm of water in the wells. When it got really hot and started boiling, it reached the height where the pipe connects to the plug top and then the problem manifested itself. At idle and when the car was not at full temp it did not reach this point and there was no problem.

Maybe you need to warm the car up and let it stay for 1-2 hours with the pipes off. Repeat 1-2 times and you should be OK (assuming what I postulkated above was right).

Chris