273sunsetZ

I've got a misfire in cyl. 5 & 4. It's not the plugs, plug wires, or injectors. What should be my next move??? Cyl. 5 does it about 20 times worse than 4....

273sunsetZ

Should i start to lean towards something mechanically wrong with it rather than electronically?

massls1guy

iTrader: (9)

I believe the misfires are calculated by the crankshaft position, so a false misfire can show up in the cylinders that are close to the 'bad cylinder' in the firing order: 1-8-7-2-6-5-4-3

You could try swapping coils to see if the misfire moves with the coil packs or stays the same.

Maybe take off the valve covers and check for a bent pushrod or bad rocker on #5.

orangeapeel

iTrader: (18)

That is where I would start, followed by a leak down test. I am going to move this over to the internal section for ya if it appears to be a problem with the rotating assembly.

273sunsetZ

I swapped one of the coil packs as well, and still the misfire... I think I'm gonna take the valve cover off next.

273sunsetZ

Thanks, I'll post a reply after i take the valve cover off. I'm going to my dads this evening to use the tools.

oange ss

iTrader: (50)

check the wiring harness on the coil packs, there were some problems with wires chaffing thru on the mount bolts causing an intermittent short circuit...not sure on probabilty but it wont hurt to check..

273sunsetZ

Thanks, i'll have to check that out.

273sunsetZ

I was gonna take the valve cover off last night, but my dad conviced me that it might still be the injector on #5. I swapped the one around for #4 not thinking about it, but from what you've said I should have swapped the one around from #5. I'm just gonna check the resistance in #5 today.

Thing is, that their isn't any racket or noise coming from top end, my dad says I'd hear it if it was a bent push rod or something.
When i pulled the plug out the other day, it was just covered in gas, so I guess the injector is the last resort before this thread gets moved to the internal engine section...

273sunsetZ

Well, the injectors resistance was @ 12.8 ohms, so it should be working properly... I stuck a screw driver up to the injector and listened to them individually and they all made the same noise... So, pretty much at another dead end! I had to drive it to my dads the other day to work on it, and it was acting VERY sluggish... the check engine light was flashing, and it was also puffing some smoke.

oange ss

iTrader: (50)

mist the coil packs and wires with water and run the engine in the dark, look for an arcing...only other radvice i can give, not very good a long distance troubleshootin...

orangeapeel

iTrader: (18)

Well, there is definitely a misfire going on judging by the flashing light. Let us know how it turns out man.

273sunsetZ

I will, it's hard to get stuff done because I'm at school all week and when I'm at home on the wkends it's just one place to the next. I'm planning on dedicating this fri. night to it though.

273sunsetZ

I've looked for an arc in the dark, but didn't mist any water over anything; sounds like a plan though.