4.7l v8 cylinder heads

[k-2]

I thought this was all after a cylinder head rebuild? WHo what went wrong and why are you paying AGAIN?



Parts my 2cents - get LOCAL - inspection and return, no time lag, tax vs shipping. you will build a relationship with local vendor that will work for you.

 

[Cherokee2004]

Thanks for the reply. I gotten a cam and now wondering about if both cylinder heads were shaved correctly. rightside (passenger) was shaved 12 thousand and the left side (driver) 6 thousand. the right side was warped from over heating more so than the right. but should both sides be shaved down the same about so both sides have equal compression ?

 

[Cherokee2004]

Now after a long process the values and camshaft has been replaced and new head gaskets on both sides. its been re-timed and put back together and now runs fine except that it sometimes stalls at stops and also coughs/chokes like at 55mph seems ok at higher speeds. Anyone has any idea what might be the issue now ? there isn't no codes coming up. I was thinking the computer just needs to relearn, but also think possibly something else might be going on like a bad sensor or something. Any suggestions ? Thanks I feel its almost back to running condition soon after 4 months of working on this beast.

 

[k-2]

Be sure to use a scanner - do not solely rely on key on off trick or the light being on for all codes.

I would check fuel pressure.


After those easy tests i would look at live data ECT, MAP, FT;s, o2 voltages.

 

[Cherokee2004]

Update, vehicle is back together starts fine, but idles rough with a little shaking, hiccup like when idling and at some speeds feels rough. Believe its clogged,dirty fuel injectors. Scan readers reads P0307 and P0306. Shop says that cylinder 6 misfires and 7 is intermittently misfiring. Going to purchase new fuel injectors and put those in Hopefully this will be it. Anyone with other ideas what might be causing this rough idle besides bad fuel injectors ? Sparks and coils are new. Thanks

 

[k-2]

No other codes? - a misfire P030x is Ignition, Injectors, or mechanical.

Maybe look at plugs -wet, dry, black, tan ?
swap coil with another see if code moves, to new cylinder
Can do same to check inj.
What type plug are you using? it matters.


then move on to
Compression and vacuum checks.

 

[Cherokee2004]

Thanks, No other codes. the plugs are brand new and dot recall the brand, but don't recall the brand. but they were compatible for Jeep. As far the coils switch goes, tried that and the same misfires on 6 and 7, So I'm leaning towards dirty fuel injectors since the intake and exhaust valves were replaced and possibly some debre might have clogged them up because of that.

 

[Cherokee2004]

I replaced all 8 of the fuel injectors and now it seems to idle even worst and has lots of white smoke exhaust, thought at first it as just fuel burning out, but still smokes after a long drive. thinking it is getting too much fuel now or that the oxygen sensors(s) are bad. possibly the compression rings are shot ? not sure. any advice would b greatly appreciated. Thanks

 

[k-2]

For mixture issues A scanner will show readings such as o2s V, fuel trims all sensor data....otherwise BASICS

You just replaced SO - maybe check for a head gasket issue, how do plugs look dry,wet, black, tan?

 

[Cherokee2004]

The only codes that come up are for misfires on 6 and 7. The head gasket was replaced just about a month ago and the spark plugs are new and do look black from firing. Sparks are dry in all cylinders and coils are good. Hoping it isnt bad compression rings on 6 and 7 or the wiring hardness Also when I placed back in the old fuel injectors the vehicle exhaust smoke stopped so thinking possibly the injectors are the wrong ones the gave me for my vehicle.

 

[Cherokee2004]

The only codes that come up are for misfires on 6 and 7. The head gasket was replaced just about a month ago and the spark plugs are new and do look black from firing. Sparks are dry in all cylinders and coils are good. Hoping it isnt bad compression rings on 6 and 7 or the wiring hardness Also when I placed back in the old fuel injectors the vehicle exhaust smoke stopped so thinking possibly the injectors are the wrong ones the gave me for my vehicle, but according to the supplier they are correct ones. could it be needing new oxygen sensors or a new evap purge control valve and solenoid ?
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Last edited by Cherokee2004​

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