Just thought I'd share my experience.

Last week Tue, at a stop light. the car started misfiring and white smoke started coming out the tailpipe. took it to autozone -p0300 code. probably one of the most useless codes out there.

the next morning, I double checked the codes with the pedal method and got p0305 + p0300

so i changed the plugs, checked the coils. and still nothing. battery died with all the cranking (RIP 10 year old optima red top - autozone said it had 400 of 710 CCA)

talked to my neighbor, who's a mechanic. he did a compression test on cylinder 5, seemed ok. but he did notice that there was gas squirting out of cylinder 5 and the plug was wet.

so finally today, after further research on the org over the past week and only finding 1 similar post on the org, and not many others elsewhere, I decided to pull the manifold off again and do a full compression test on all cyclinders and check the injectors.

sure enough, once my gf turned the key on, injector 5 was spraying all over the place and the others seemed ok. so onto rockauto to order injectors and wait a 2nd week to get the car back.

 

figured the 1st post was getting a bit long so here are the compression results:
1 - 190
2 - 170
3 - 185
4 - 170
5 - 160
6 - 170

seems ok, but the car is an oil burner. roughly 1 qt every 3000 miles. any thoughts? suggestions?

i'm replaced both valve covers from a 6th gen. but may do the rear again just to be sure.

 

1qt every 3k miles is pretty "normal" for the 3.5L engine. In fact, it might be better than average.

 

Compression is good. Save it while you can and delete the precats.

That is normal burning, but it will get worse fast when the precats **** the bed.

 

White smoke that's only there if you have a head gasket issue,are you loosing or burning any coolant,because that will also cause you to misfire. The 5th cylinder looks like it's a very low on compression. Keep us posted about that open injector.

 

lots of unburned fuel can cause white smoke. and in lots i mean stuck injector that can hydrolock the engine lots. radiator tends to hold coolant pretty well.

finished putting back together today. did the injectors, headers/ypipe/cat. what a pain. no broken bolts, just lots of dropped sockets and cursing at the rusted bolts underneath. seems to be holding up so far so good. took it around the block. going for a longer ride after i mow my lawn and take a shower.

 

forgot to mention. the precats are in tact after 175k! partly clogged, but in tact.

 

So...did you figure out what was causing the White Smoke ?

 

yup, it was a stuck injector - # 5.
i pulled the fuel rail, switched the ignition to on (actually had my gf do that while i was in front of the engine). the injector shot a constant stream of gas.

replaced all 6 and good as new.

 

acw, thought i'd help you out by posting here.

"...mine is regularly losing radiator fluid, occasionally blowing white smoke, AND ALSO, misfiring."

i'd say to check your oil to see if any coolant is ending up in there. how much are you losing? have you done a compression test?
i've never had a head gasket problem, so i'm not positive, but i think misfiring is unrelated.
what codes are you getting?
misfire could be spark plugs, or coils

 

This sounds like an unfortunate case of blown headgasket denial. Unless the OP is actually seeing blue-ish smoke and NOT white, he definitely has a head gasket failure. NOTHING in an internal combustion engine will create white smoke, other than coolant being burned...unless it's just condensation sitting inside the exhaust system, though that would be gone once the car is warmed up.

 

seeing as how it's now 2 months later, over 1k added and no loss of coolant or return of misfire/smoke. if it's denial, i guess ignorance is bliss.

 

Gonna have to disagree with you too. On both my boosted 98 Maxima, and my friends Maxima, we both had white smoke pouring out. I fixed both of them by finding a single bad fuel injector.

FWIW, I thought it was a blown headgasket at first too, and did the quick and dirty headgasket test, and they both passed.

 

Good work Wiz!

Hey cil,

1. No Discoloration or coolant "ON OIL DIPSTICK"
2. I HAVE not done a compression test (gonna try the block test as its only $40 to check for gas in cooling system---since its $40 i'm guessing its easier and cheaper than compression test)
3. I'm getting the codes, "0306, 0300",
4. I just changed the Thermostat,...and still loosing coolant and over-heating---ONLY after 20m+ drive.
5. I'm gonna do another pressure test this morning to see if water is still dripping near the Thermo.

`Thanks Man!

 

So what happened...what was the final conclusion?