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Misfire tech in chit chat

dntsdad

Central California
Joined
May 19, 2020
Member Number
47
Messages
1,269
Loc
Central California
97 3.4 4Runner engine

Worked fine. I swapped out the battery and then #2 is misfiring. Noticeable miss when driving under load.

1. Swapped plug 2 and 4. No change. Still misfiring on #2
2. Swapped coil packs. No change. Still misfiring on #2
3. Swapped in a new injector in #2. No change. Still misfiring on #2

Getting spark at #2 plug

Continuity between #2 injector wire and injector plug and ECM

No idea what to try from here other than compression and leakdown tests. I just can't see that going to shit from a battery swap but I can't see anything really going to shit from a battery swap. Has to be a coincidence.


Any ideas from those smarter than me?
 
Any codes?
and did you try disconnecting the battery and letting it sit. like doing a reset
 
Did you check the spark plug wire to make sure its not grounding out?
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Any codes?
and did you try disconnecting the battery and letting it sit. like doing a reset

It did throw a misfire code. That is how I knew #2.

I did disconnect the bat and reset it. Nada. But now the code doesn't come back, even after multiple restarts of the ignition.

I have swapped the plugs around with same result.

I have been trying to avoid just throwing money at it.
 
I also have a #2 misfire code on a 97 4runner:laughing:

my plugs and wires are due tomorrow. I found my wire really shabby, probably broken internally where it makes the 90 into the tube
 
#2 is front left, right behind the battery, not out of the question you tagged the wire swinging a battery or put a hand with some weight on it
 
Ok well I guess I will throw some new wire and plugs at it and see what happens.

Probably a good idea to change them about now anyway. They have been on there a while
 
ToyotaReliability(TM) must have ran low :flipoff2:

Throw a fuckin spark tester on #2 to see if it's getting spark.

When that doesn't work check out the fuel situation.

When that doesn't work go looking at compression.

It's not rocket science.
 
Is #2 actually misfiring? Do you know how to read spark plugs? On one had that cyl's proximity to the battery makes the connection between the two seem likely, on the other hand I've seen plenty of people chase plenty of problems while looking at the wrong parts, just because "well thats what the code reader says"
 
I've been bit by bad plug wires on my 97 Taco. They weren't that old so I went through other stuff before I just gave in and got them.
 
Check the resistance of the plug wire while moving it around. My money is on you smacked it with the battery getting the old one out somehow and have a broken wire internally. Or at least thats what I did on my wifes old 3rd gen runner. :homer:
 
My plugs and wires came in today, night and day difference

FWIW mine didn't throw the misfire code until I was trying to get on the freeway floored to outrun a semi
 
Yep. Me too. Not sure what the issue was but new plugs and wires fixed it. Also, replaced most all the vacuum lines with silicone ones while was in there.
 
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