rough idle and misfiring 3.0r

[darthqwo]

I stepped hard on the accelerator from 0 to 60 for about a quarter mile, going through all the gears, and then came to a stop. This is the first time that this happened, but the engine was misfiring on all cylinders and almost stalling out, even though it is a 5EAT automatic. I went through a few turn-on-and-off cycles a few times, looked in engine bay for loose hoses found none. I just misfired on and on; engine shaking from misfires on the mounts; een the exhaust was noticeably rough.

 

Mine auto has been done to a fuqtun of maintenace: all vacuum hoses new, timing chian tensioners new, water pump new; new 5w30 synthetic oil and coolant flush and mani-fold atf drain and replenish. When i replaced the timing tensioners two weeks ago, the LH exhaust cam was off by one tooth, and even this was fixed. Fuel injector, ignition coils, spark plugs also all new.

 

Apart from that It makes a whining noise audible at startup, idle, and low-speeds that at this point is coming from a transmission bearing or back side of the engine; i listened on a mechanic stethoscope, and there is no sound from the timing cover or ps pump but is the same type of sound. If anybody has any comment what it might be, please let me know. Fuel pressure was tested not long ago and strong. Despite sound transmission shifting very smoothly in all gears; previously slipping 30% of the time between 2nd and 3rd, but with another atf drain cylce, this is almost gone but still there maybe 5-10% (if anyone notes p0700 is codes, that code no longer flashing but happend during drain.) Perhaps ECU needs reset after the timing tooth of LH exhaust gear was fixed? Maybe transmission is dying anyway and caused this?

 

Pressing on the gas pedal would accelerate the misfires to a degree; throtlte response delayed from stop to due the lack of consistent power in all cylinders. Diagnosed for 30 mins, but i just started driving off again, and then it just stopped misfiring and went back to normal without a single misfire. I am lost as to what had happened. Any body have ideas? omg thanx

Edited June 26, 2019 by darthqwo
screenshots out of order; 3rd is misfire codes; 1st is codes when misfire stop; 2nd when stopped misfiring when drove off

[darthqwo]

So given ive replaced everything else the only thing left is egr valve which on this car is hiding under the intake manifold; i hope it is sufficient to spray it down with brake kleen. comments?

 

i also still have an air leak, just letting 'erbody 'no, at the intake manifold. So with these there is probalby nothing left to repair on the top of eingine. as for the other thing on the tranny i may add some lucas fix for transexuals

Edited June 27, 2019 by darthqwo

[GEE-OTTO]

What intake do you have, is it the filter tube or the whole intake tract from the throttle body to the filter (Kakimoto style) ?

 

 

 

If you moved the MAF around that could be a culprit also have you ever changed out the AFR sensors? O2 sensors? MAF sensor?

[darthqwo]

Just the stock intake: throttle to airbox to hose with MAF sensor to air filter box to snorkel. Maybe i could reclean the MAF; right now i am driving around withtou the undercarriage and right wheel well moudlings, so there bunch of soot at random places

 

I have never changed the sensors on the exhaust. Is there a way to tell if the o2 sensor is bad from looking at the data; in particular, i have never seen "O2 Rear (V)" change from 327.7?

 

Also, this guy did the

as me with same result (but seems to blame o2 sensor in comments)

 

Anyways I went back on freessm on debian linux and cleared absolutely everything (ecm and tcm).

Edited June 27, 2019 by darthqwo

[forensic_eng]

I recently had rough idel. I took throttle body off and cleaned...with o'Reilly throttle body cleaner. Cleaned MAF with PB blaster.

 

Fixed rough idel.

 

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[darthqwo]

So now I am getting a persistent misfire in cylinder 2. On startup it misfires some 10 times every 10 seconds until i start driving, at which point it is occasional at low rpm, such as everytime it shifts down.

 

I already replaced the spark plug and is still happening. Any ideas anyone?omg thanks

[ehsnils]

Did you replace PCV valve?

 

 

Also make sure that all connectors are properly connected and that the ignition coils are clean (use brake cleaner, not WD-40 since the latter leaves an oil residue that's bad for insulation)

 

 

Also check the injectors, you may have an injector that's bad. Make sure the injectors are well matched too.

[darthqwo]

i'm an idiot. i replaced spark plug #4 instead of #2, which has the misfires.

 

i put the plug taken out from #4 into #2; now the misfire happens just once or twice instead of ten times; so probably it was the spark plug that fouled; im inclined to think the spark plug from #4 also has issues, so eventually that will be replaced, but i am still scratching my head

 

i guess will hold off doing another aggressive pull until after i clean the egr valve; i will probably need new egr gaskets

 

yes, pcv valve and pcv hose both new

[ehsnils]

OK, just replace all plugs at the same time, it's worth it. Having a car with mixed plugs is just a problem waiting to happen.

[funnyman06]

I had to replace a bad coil pack on our outback. Misfire went away after that.