the hooker

my 2000 altima 4 cyc misfires on no.4 when idling,changed plugs.wires ,cap,rotor. checked compression 165pds ran inj cleaner code misfire help please

 

NotAnotherHonda

hmmm...all the wires are hooked up correctly of course, right? are the plugs gapped correctly?

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95 200sx se. sr20de, gt28r, bb manifold, forge fmic, greddy bov and bc, tial 38mm, walbro 255, apexi tt, 3" exhaust with magnaflow, 3" downpipe, jgy clutch flywheel and fuel rail, msd 50#'s, cobra maf, jwt ecu and s4's, nismo fpr, autometer, nissport adaptors, fal pushers, ur pulley, m/t 22x8x15 et drags.

FREDANDTA

could be internal coil misfire. remove dist cap and look for signs of jumped spark on the coil. hope this helps.

motorider475

my 97 nissan harbody started doing the same thing, only right about 2k rpm.
Started out as egr code, found vacuum leak on egr and fixed it, egr code went away but misfire on cyl 4 partial throttle low load now, obdII only says misfire cyl # 4.....grrrrrr.......could my egr be opening too soon? and if so why would it only cause misfire on cyl 4?

3martini

I just had the same issue on my 99 Altima. Although I have the same problem that motorider 475 had with the hesitation at 2000rpm (EGR related) the fix for the misfire was replacing the intake manifold gasket. It had become brittle and cracked.

I heard one way to diagnose this is to spray some carb cleaner near the #4 cyl intake manifold gasket and see if the idle changes (because it temporarily changes the mixture). I never tried it though.

 

eetnoyer

The carb cleaner check works. One quick spray between the manifold and the engine housing by cylinder 4, and the engine revs. I have the same P0304 error on my '00 Altima (second time in ~3 years). Try searching google for "altima P0304". Pretty much the entire first page comes back with the intake manifold gasket issue. It seems that this particular engine ('99-'01) suffers from somewhat of a design defect that causes the gasket to get baked and prematurely fail due to heat degradation. Always happens in the same place. The first time, I had the dealer fix it for ~$600. I'll be d@mned if I'm going to pay them for it again. I'll do it myself this time.

Kraut-n-Rice

If the manifold gasket is leaking ,its a cheap fix when its a DIY job. Gasket is about $15-20 and takes a few hours to change . Buy a PCV valve at the same time ,because its behind the engine and difficult to do otherwise. Also the PCV valve if it fails in a higher mileage car will cause high crankcase pressure . That pressure will force oil past the distributor shaft seals and ruin a distributor .