Possible Misfire?? Big power loss, help!!!
 

Alright heres the story. I was reading on how to make your own CAI on the org, and went ahead and disassembled mine. I took down to the MAF sensor, and left it open air (no filter) with only that small wire mesh as my protection. Well, its been raining here, and I went out to test my car out to check the difference. Right away you could tell a significant difference, I was heading in to town. Me and my friend was on the interstate, he drives a Celica GT 91, and we were racing off and on. Everytime ive raced this kid, Ive smoked his *** bad, but this time...I saw him downshift and get on it behind me, and as he came level with me I got on it. Usually, it takes a few seconds for me to pull away...but he actually pulled away from me. I was f*ckin flipping out, and when we got to the 4 way, I noticed my car was shaking real bad, and had really low power. I remember my friends sentra had a misfire, and it sounded like there was someone cutting out a piece of the sound coming from his exhaust, a choppy sound. Well Im getting the same thing. I went to Wal-Mart immediatly and bought some Isopropyl Alchohol **** for your fuel line, water absorber. I put it in, and drove home (10 minute drive) and theres no difference. Im about to go check my ECU code, and my plugs, but I wanted to know if it could be one of these things:

1. Water got inside intake and hasn't escaped yet
2. Water hit the spark plug somehow and made it defective
3. Its not relative, and I have another problem

Should I wait for the solution I bought to react and go check in an hour or so? Help!

Alright, I ran the ecu and got the following codes:

0401= Intake Air Temp Sensor
0302= EGR System HI/Low flow

Can anyone tell me what the 0302 code means? I put my stock air box back together as soon as I noticed the power loss at the 4-way, I forgot to mention that. So maybe the temp code is from when I had it running open air. Help me please?

No filter? Just your MAF hanging out by itself? :slap:

Man don't EVER do that! Pull off your EGR and clean it WD40 works fine. Make sure you work the valve up and down, so it's nice and free. Get some Quick dry electrical cleaner and clean your MAF, might as well clean your TB while it's all apart too. Put it back together WITH THE FILTER. Clean your plugs and change your oil. Clear the codes from the ECU. Hopefully you get lucky and didn't screw up the MAF. As far as the air intake sensor goes, make sure it's put back in the airbox and connected properly. BTW, no-one has ever mentioned running your car with out an airfilter. Part of the air intake mod is to either drill holes in the bottom of the airbox(OSCAI), or pry the MAF adapter out of the airbox and clamp a cone filter to it.(Ghetto WAI) Cheers.

Your problem was runnning the car with the MAF open like that. The MAF can't properly read air flow when it's operated with no piping. The signals from it were probably way off causing your engine to run poorly. Put your intake back on and drive around for a day or so untill your ECU corrects itself.

On a side note, you could have damaged the MAF by doing that.

Thanks alot. After I ran the water absorber//fuel antifreeze ****, the motor has gained a little bit more power back, and dosent vibrate as hard at low idle and take off. It still sounds like im missing, my exhaust isnt loud at all anymore and you can feel a break in the exhaust fumes coming out, like a water sprinkler. Im going to change my plugs today and hope that it fixes it.


Ill try to figure out how to take the EGR off and clean it, thanks though. If you have anymore helpful information about removal of the EGR valve, etc~ Id really appreciate it. Thanks~~

The MAF sensor isnt giving me any CE lights, and when you disconnect it, your ECU still kills the engine. It seems to be working correctly, and I put the stock airbox back on right after this happened.

What I had done was taken out the 4 bolts connecting the MAF housing to the airbox, and removed the top part of the box, revealing it. Bad move I guess, lol. I was so excited about my slight power gain and the new *race cur* noise, that I just wanted to go o_o.

On my car, ('93VE), there was only two bolts and a huge a** pipe thread holding the EGR valve on. I don't think the VQ is much different. Use some penetrating oil ond undue the big pipe at the bottom of the EGR. Remove the two bolt's that hold the valve on and wiggle it off. If your lucky, you can even reuse the gasket!

I went out to drive the car as you said, so I could hopefully get the ECU to recover. I went to autozone and got some new plugs to put in, and on the way back I noticed my CE light would blink in coorispondence to my RPM's. Higher the tac., faster blink. When I got home I identified it as cylinder #5 misfire. When I took the plug out, a ****load of oil came with it, and the plug capsule was melted on the end. Im taking another car back to get the new capsule now, but im extremely uneasy about all that oil..and only in that 1 cylinder. Thanks for all your help.

Plug capsule?

Coil pack, sorry. My coil packs melted on cylinder #5, im screwed. Why are coil packs so hard to find?

go to jerryromenissan.com they are $60 oem with "maxima" promo code

First, I would figure out why your coilplug melted! Is there a short or a problem in the wireing harness? Or was there a short or crack in the coil? I'd figure that out first.

I got a new coil pack, didnt work. This has happened before, but when my dad owned the car the coil pack was replaced and no more problems. This time, its serious though. Car wont even run right, I mean I can drive it but all the gas going into that cylinder is just venting throughout the exhaust.

I am trying to figure out why in the hell you drove around with out a filter! What in the hell made you do that?

Get a haynes or Chiltons and a multimeter, and start testing the coilpacks and the wire harness. Make sure eveythings in spec before assuming the worst. If that all checks out, ur gonna hafta pull the valve cover, and maybe even the head to find out what's going on. Good Luck.

I switched plugs around from cylinder #4 and #5, coilpacks also. Im getting 2 errors still. The first is Cylinder #5 misfire, and now Im getting Air Temperature Sensor error also. I assume the 2nd error is from me being a dumbass...

Thanks FNG, ill proceed with the multimeter, I didnt even think to check the wiring harness. Ill keep everyone informed... if you care :/

How would you test the compression on one of our engines? Because of how deep the coil pack is, I dont know how to tighten the stem of my Comp. tester with any convensional wrench. Is there any kind of attachment I can put on it to tighten it?

I suppose you could look for a longer hose to attach to your tester, but I would tighten it up as best as you can by hand, it should be enough.