Hardcore misfire

[Typrus]

My sisters boyfriend drives up to myhouse today in his 93 Camry (5SFE automatic)
He's been complaining to me about "transmission problems" for some time now, but I never got a chance to look.

So, today, I go to drive it. Fire it up. Runs real rough. Sounds like 1 or 2 cyl's are misfiring. Rev it. Holy God is it misfiring. Sounds like an oldschool lawnmower.

So I go to pull plug wires to see which cyl is the culprit. Pull #1. No change. Dead cyl. Put it back and pull #2. No change. ANOTHER dead cyl. Put it back. Pull #3, it stumbles and dies. Good cyl. Put it back, start it up, pull #4. Dies. Good cyl.
Go to start it again..... Nothing. Just a few half-hearted kicks. Crap.

So I roll it off to the side of the driveway (rural house)

Had an appointment, so I head off. I'll get back to it.

Get home, and start looking. I had some spare plugs from when I put the Denso IX's in my Camry, so I figured it'd be an easy plug change, problrm solved.
Pull 1 and 2. No surprise they were fouled to hell and back. Pop in the decent ones. Pull 3 and 4. A little nasty, but functional. Put in the other ones anyway.

Go to start. A few miserable kicks, then nothing at all. Double crap.

I pull the cap. Looks decent, a little old, but decent. Rotor as well. Wires are acceptable. Didn't ohm the coil though.
Put it back. Try again. Nada.
Replaced the fuel filter (I had one, so why not?)
Nada.

I grumbled some and started checking fuses. All good. Relays fine.

Try again. A few miserable kicks.

Took the negative off, cleaned the terminal (then cleaned the +) and left it off for an hour.

Tried again. Miserable kicks.

Waited. Tried again. Miserable kicks, followed by a halfhearted idle (with me feathering the throttle)
Kept it there for a while. Still sounded bad.

After a while, I started trying to blip the throttle. At WOT it bogged but stayed at the same RPM (intake sounded like the rev-limiter was going off)
Find the sweet spot, it got silky smooth and revved up, let off or added throttle, and it went to hell again.
After a while of doing this I notice the smoke blowing by. I stick my head out and smell it. Oil. Smells like burning oil. Awesome.

After a while of trying to get it to fix (btw it wouldn't idle without my help) itself, it just plum quit.


So my question is.... Is there something obvious I need to check for him? Coil bad maybe?

Think maybe #1 and #2 cyl's are shot? It has 170k miles on it and he doesn't really take care of it.

Need some thoughts so I know what to tell him. Lol... still dunno if the tranny is any good, but the fluid sure smells fine.

[Unco]

if it was the coil, the problem would be on all cylinders, not just 1 and 2.

are cylinders 1 and 2 getting any fuel? try pulling the spark plugs out of 1 and 2 and clean them out. put them back in and start it up, then pull them out again. see if they're wet. if they are, that's good, it means you're getting fuel there. if they're not, it's a fuel delivery problem to those 2 cylinders.

if you do get fuel there, then it could be a spark problem. check for faulty leads (do you have any spare ones?)

do a compression test too if you can. you may have a couple of stuck valves on both cylinders.

[Typrus]

All cylinders getting fuel.
No cylinders getting good spark it seems. It seems that pulling off the wires was the last straw for whatever part.

Some kind of sensor perhaps?

I imagine that maybe if a few cylinders (be they still #3 and #4 or not) are firing and a few are not, the slight vacuum of a forced power stroke against closed valves might draw oil past the rings and force it to burn some.


But see, thats the thing, when you'd hit that "sweet spot" on the accel. pedal, all cyl's would feel like they were firing. Buttery smooth.

I'm going to go out and try it again this morning. I think my Camry is a bit pissed at me though for using its alternator through all that last night.

[fabbb]

I recently had a similar experience on a 94 2.2 liter. Car was cold and would not start. Pulled the plugs and I was getting spark. Had fuel ect... swapped in my spare distributor and it fired right off and ran like a champ. Did all the checks on the coil and it was fine. Bit the bullet and bought a new coil and compared values and they were the same. Put the new coil in and that was the problem. You may have spark, but not great spark. Testing the coil with a meter is not a sure test for a good/bad coil. Just a thought. My coil cost about $25 at Advance Auto.
SteveB

[Typrus]

Pulled his coil.
Primary coil resistance- 200U mode- .000. 2kU mode- .001. 20kU mode- .001.
Secondary coil came to 16-somethings Ohms.

Bum primary?

[95PimpingCamry]

I had a problem with my coil about a year ago. Resistances checked out on the meter, but whenever the engine would warm up it would misfire, probably because the coil is right next to the engine and heat can change the resistances. I replaced for $35 at Advance Auto Parts and the problem was gone. So i would suggest spending just a couple dollars and replace the coil, it will probably help.

[Hajoca]

Is the distributor cracked? I serviced an accord once with a cracked dizzy, and only saw that when I water misted it to see where the insulation was broken, I suspected bad spark plug wires.

[Mike Gerber]

I also feel that it's the coil, but since it's only cylinders 1 and 2 that are causing the problem, there is one more simple test that you can try. Pull the plug wires from cylinders 1 and 2 and test them with your digital volt/ohmeter. Don't be surprised if you find high resistance or even an open circuit. They may have interal cracks that do not allow the spark to jump the crack and properly fire the plug. They may exhibit a slight spark with the plugs out of the engine (no compression) but can not transfer enough voltage to fire the plugs under compression. As an alternative, you seem to have some Toyota ignition parts lying around. If you have some old (but good) plug wires or the wires from your car, try and exchange them with plug wires 1 and 2 on this 93 Camry. This would be a test of his plug wires.

Mike

[Typrus]

I have him picking up a new coil.

I re-iterate- all cylinders are now causing a problem.

When I pulled out the Champion plugs he had in there (ew)
#1- fouled badly
#2- fouled badly
#3- nasty
#4- nasty

Now, the question is- where they not firing due to fouling? Or were they fouled due to not firing?
If fouled from the non-firing, one could reason that the coil was weak, and barely kicking over #3 and #4. Pulling those wires may have caused enough stress on the already weak coil to make it die the rest of the way.


Thoughts regarding this?

[Typrus]

Installed new coil. Now idles smooth and revs smooth-ish when cold. Gets hot very fast then runs like crap if at all.

[dc_98_cam]

Originally Posted by Typrus

Installed new coil. Now idles smooth and revs smooth-ish when cold. Gets hot very fast then runs like crap if at all.

From this description, it might be that there is carbon fouling within the combustion chamber .... Is there anything that you might describe as pinging or knocking ... as you rev it up?
You might also remove the pre-cat O2 sensor and see if it has any kind of fouling or buildup on the sensor tip.