In-tank fuel filter; dirty?

[docdread]

Getting rough idle and poor acceleration. Wires, plugs, dist/rotor vacuums all ok. Guessing fuel pressure is low, so I'm replacing the main fuel filter on engine. Question is does the in-tank filter get as clogged as the main filter and will I necessarily need to change it as well? Too much work, I'm hoping the front filter will be all I need to change...

[kamesama980]

when the in-tank sock gets clogged it's with bigger stuff and it usually will start to hesitate and fall on it's face when you want to go fast. then you stop or turn off the engine and the crap falls off the sock and you have power again till it sucks up the crap again. the solution is to pull the pump assembly and put a new sock on and clean the crap out of the tank.

[docdread]

Not getting those symptoms so hopefully its just the main filter. I will replace it over the weekend, that thing is way down there... I'm guessing I will need several extensions to get to it. Thanks Kamesama

[toyomoho]

carb or fuel injected engine?

[docdread]

fuel injected mx83 with 7mge engine

[docdread]

Finally replaced the fuel filter and even though it was the original 18 year old Nippo Denso one it wasnt clogged or anything, and I could blow through it almost as easy as the new one. Predictably it didnt make a difference. However I had a couple old plug wires (cylinder 6 5 and 4) swapped them and there was a small difference, idle is now only shaky in drive (or when fan/brakes/ lights on etc) and not in Park or neutral. Guess the wires were worse than I thought so I'm replacing the set.
New question, cylinder no 6 (counting from front) appears dead, and removing the wire from the distributor wont make a difference in idle. Removing other wires makes it run rougher instantly. Could it be no ignition in 6 or nothing to worry about?

[stepho]

If pulling the plug lead from #6 made no difference then #6 is not doing any work.
Likely causes:
- bad spark plug lead
- bad spark plug
- bad compression caused by bad rings (blows smake>)
- bad compression caused by bad gasket (oil looks like milkshake or can see bubbles in radiator)

Hopefully it's just a dirty spark plug or the spark plug gap has been squashed closed.

- Stepho

[kamesama980]

Originally Posted by stepho

If pulling the plug lead from #6 made no difference then #6 is not doing any work.
Likely causes:
- bad spark plug lead
- bad spark plug
- bad compression caused by bad rings (blows smake>)
- bad compression caused by bad gasket (oil looks like milkshake or can see bubbles in radiator)

Hopefully it's just a dirty spark plug or the spark plug gap has been squashed closed.

- Stepho

you forgot things like bad injector/injector wiring or burned valve.

blown head gasket would cause rough running from coolant entering the cylinder long before you lose compression enough to be a 'dead' cylinder. I almost hydrolocked #6 with coolant (starting it after sitting) but pulling that wire didn't make any less difference than the others while it was running.

*mod note* removed "coolworld"s counterproductive post
*mod note 2* removed "carcrazy"s counterproductive post