my new xl...... is mis-firing....

[garyphelps]

stumble upon takeoff

ok sojust got my hands on a 96 xl 4.0 2wd. they thaught it had bad tranny...turns out had bad radiator ,leaked all the tranny fluid into the cooling system...heres some pix after 3 days of wrenching and cleaning....the whole inside was molded, had to powerwash the carpets and the seats and clean every inch of plastic....it was tough.......http://photobucket.com/newexplorer?albumview=grid

the problem......

its got a pretty bad miss as well as lack of power. i'm throwing no codes, decent looking plugs and wires, new fuel filter, seafoamed, cleaned IAC, and cleaned MAF. the air filter is in pretty good shape as well. i cant tell you when it started doing this as i just baught the truck and am getting conflicting stories about how long its sat parked.there was a 1/4 tank of gas in it and i added another half tank of 93 along with the 2/3rds can of seafoam. there's no back firing and i cant seem to find any cracked vacuum lines and whatnot. i have also checked fuel pressure its sitting @ 40lbs. the only thing i can think of that i havn't done is a compression check, figuring that if one of the cylinders wasn't working correctly id'e see it on the plugs or it would throw a code.... any ideas?

 

[garyphelps]

update....it seems to @ its worse when its cold....once it warms up seems to be alot better but is deff still there...any help please!!!

 

[freak]

Look for corrosion in the coil terminals. Check the wires and plugs... Don't just look at them. Misfires don't always throw codes. Could be an injector problem.

 

[garyphelps]

thanx freak....i havnt worked out the mis-fire yet but now im gettin a code...im gonna go get it read today. a code poped up this week p0401 i think it was general egr code....currently working on that....

 

[Fox Fader]

So you are having EGR problems.
I'd start with pulling EGR valve and clean it, make sure it seating properly, (I think it may be stuck open some) make sure the branch from the manifold is clear, the hoses to the DPFE are clear. If all that's good I'd replace the DPFE and the EGR solenoid. The can be found on Rockauto.com. Airtex product is ok to use, redesigned and a lot better than before.

 

[garyphelps]

So you are having EGR problems.
I'd start with pulling EGR valve and clean it, make sure it seating properly, (I think it may be stuck open some) make sure the branch from the manifold is clear, the hoses to the DPFE are clear. If all that's good I'd replace the DPFE and the EGR solenoid. The can be found on Rockauto.com. Airtex product is ok to use, redesigned and a lot better than before.

thanx fox...today i got a wedding to go to but im gonna give all that a shot....i know the hoses are good, i replaced those as a precaution already....it had the aluminum DPFE i switched to the plastic one off my old x and no difference...the hose leads into the old one seemed pretty guked up so i wonder what the inside of the EGR looks like..... after wedding wrench-a-thon it is......

 

[garyphelps]

woohooo got me some codes!!!!

it feels terribly weird to be excited about getting some codes.....but anyway i went to the zone n got my codes read and this is what i got...

p0304- cylinder number 4 misfire
p0301-cylinder number 1 misfire
p0401- EGR insufficient flow


so tomorro ill dig into the plugs and see if i can get the egr off too.....


ohh happy day!!!!!

 

[garyphelps]

ok so i got the number one and number four plugs out......all seems well....gap is good they look no worse than any of the others...no cracks nuthin.....got my egr off too...in the process of cleaning it out.....so if plugs look ok im gonna test the wires and then i guess looking to the injectors would be next? any chance my egr would cause the misfiring in those two cylinders?

 

[garyphelps]

almost there.....

ok so replaced plugs n wires.....none of the plugs that were in it were gapped right...all of them were around .43.....also cleaned the egr really really good and tested it to see if it leaked internaly and no, it was fine....i do still have some hesitation though....so ide say its 50% fixed....any ideas? i guess ill just have to wait and see if my CEL comes back on....



later that day......

so i took it for a test run to wally world....ran great, still stumbles a bit on take-off....also whenever the a/c is on its a real dog....i know it should dog down a little when the a/c is kikn but this seems crazy......any ideas guys? i really really wanna get this figured out and just dont have the money to swing it by a mechanic......

 

[garyphelps]

i should add that when its idleing in the driveway and i just tap the gas pedal it makes a little sucking sound in the split second before the engine reves up...any ideas?

 

[garyphelps]

so the problem is....

it seems to go from light to light......runs great for 5 minutes and the next time i stop it runs like dooo dooo. take off runs crappy for a bit get it to 55...smooth sailing...till you hit a hill...then it bucks somewhat and then downshifts and the next time it returns to overdrive and get to 55 its fine.....till i stop again poopy idle returns....lets recapp the work thats been done....


cleaned MAF with proper cleaner
seafoamed twice....
cleaned IAC,EGR and throttle body.
btw the EGR doesnt leak internally...
replaced fuel filter, tested fuel pressure.... its good.
new plugs and wires gapped @ .54
replaced DPFE not with a new one but with one that worked fine on me old x....
new little sensor (the name escapes me) that goes in the rubber intake tube.
new PCV as well as new rubber boot for it.
also checked for vacuum leaks with propane as well as with carb cleaner

im friggin stumped guys... everything i do to it it gets a little better... please someone help!

 

[jd4242]

lower intake gasket.check and see again if your getting water in your oil or oil in the water

 

[garyphelps]

i did check the oil and water as i did a change on that today too ...nuthing out of the ordinary......

 

[jd4242]

id still try an compression test

 

[garyphelps]

thnx man...ill post results tomorro or tuesday...

 

[garyphelps]

ok so today i got codes again....again with the misfire on cylinders 1 and 4.......what would continue to make this happen after all ive done....i mean half the day it was running friggin sweet......grrrrrrr please please help

 

[freak]

I've tested plugs/wires by putting in a dummy plug and testing the wire/plug with it running and the plug grounded externally. Watch it to see if there is a steady spark.

 

[garyphelps]

I've tested plugs/wires by putting in a dummy plug and testing the wire/plug with it running and the plug grounded externally. Watch it to see if there is a steady spark.

plenty of spark all the way around....i keep trying to think of what could poss cause the misfire on number one AND number six.....i dont get it....i'de think if i had a compression/bad rings type problem it would be on one cylinder not the both and ide also think that ide see some evidence on the plugs....i see no oil in the water, no smoke. good spark, new dpfe, solid egr, new pcv, new plugs and wires.....i think im gonna swap out coilpacks today.....just a shot in the dark....maybe ill get lucky and find a vacuum lead i havnt checked a hundred times already......

 

[jd4242]

normally when a coil goes bad it will show a miss fire on 1&5 or 2&6 or 3&4 there is really 3 coil in your coil pack and each one of those share a coil

 

[garyphelps]

normally when a coil goes bad it will show a miss fire on 1&5 or 2&6 or 3&4 there is really 3 coil in your coil pack and each one of those share a coil

so using that theory for the coilpaack to need replacement and me get the codes im getting it would also misfire on 3 and 5....so skip the coil pack....