Spark Knock

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JUST4FUN

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I thought Cam phazers are specific to 3v and 4v motors with the variable valve timing. The 2v motors do not have cam phazers that I am aware of. I assume the op has a 2000 expy motor ??

"yes thats what i dont understand,,u think that 10w-30 gonna make it do that,,if it does ill be happy to put 5w-20,only reason i did cause of morning rattle for that 1.5 sec ,thought it would help that out"

Rattle on start up is likely caused by lack of oil pressure or oil bleeding out of the passages. This is not normal. What oil filter are you using?? The oil filter has a check valve to prevent this bleed down.
ford only recomends 5w20 in the modular motor. fram spends all there money on ads and nothing on there filters IMHO they suck
 
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I thought Cam phazers are specific to 3v and 4v motors with the variable valve timing. The 2v motors do not have cam phazers that I am aware of. I assume the op has a 2000 expy motor ??

"yes thats what i dont understand,,u think that 10w-30 gonna make it do that,,if it does ill be happy to put 5w-20,only reason i did cause of morning rattle for that 1.5 sec ,thought it would help that out"

Rattle on start up is likely caused by lack of oil pressure or oil bleeding out of the passages. This is not normal. What oil filter are you using?? The oil filter has a check valve to prevent this bleed down.



fram filter,oil presure looks good but whos to say that gauge is right,but that bleed off make sense,ill change filter with new oil
 
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ok i was just told by my cousin that was reading the scanner ,he said the rear o2 sensors were rich at all times and ran at .67-.74 volts,,it did not change like the front ones did?????? ok now we on to something else
 

toms89

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"I ran it on the scanner and when it started to spark knock we watched the timing retard to 3-5 deg and it was still spark knocking and cant figure out why it spark knocking when the timing retard's down to 3-5 deg,"

It sounds to me as if the knock sensor is working. My concern would be why is it knocking in the first place.

Possible causes as I see it.

1-too much timing advance.
2-air/ fuel ratio to lean.
3-hot spot in combustion chamber.
4-egr not functioning properly.
5-compression ratio to high.
6-fuel octane too low (if contaminated with oil can have same effect)
7-too much boost for fuel octane (can rule this out :) )

You mentioned the rear O2 sensors read rich. Now I really don't know how the computer reads or adjust for the rear O2 sensors but generally I would assume if the computer believes the air/fuel ratio is rich it will continue to lean it out till it gets the reading it is looking for. I believe if O2's get contaminated by lead, coolant or ?? they will react slower and read rich. (based on experience with my mustang)

It would be nice if you could test your air/fuel ratio to rule this out
 
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what should the spark plug gap be,,i didnt gap them just put them in straight from the box,,starting to think gap is to big,,,still chasing this spark knock
 

toms89

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.052-.056

Should be on the radiator cover..

Never install out of the box.. Always properly gap your plugs.

Doubt it would cause spark knock though..... If gapped to large you can get misfire under load. Too small just not as efficient.
 
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.052-.056

Should be on the radiator cover..

Never install out of the box.. Always properly gap your plugs.

Doubt it would cause spark knock though..... If gapped to large you can get misfire under load. Too small just not as efficient.

i dont have that cover ur talking bout nor the belt route sticker,,when i put the new plugs in i thought the gap was to big but ive always done that with other motors but this one just acts way to funny,,i do notice a lil mis in morning while warming up and then when i take off is when it turns into spark knock,,,at cruising speeds its fine just down low is when i notice it ,yesterday i drove it home all the spark knocking and what felt like a miss when conv locked up at low speed and no cel,,hmm
 
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:headbang::mfr_omg::signs1::happy160::pepper::big_banana_Dance:

Well remember in original post i said i bought summit brand coils,,well last night i checked gap on plugs and they were .045,changed out the coils to original motorcraft and drove last night for 50 miles and it was good,,,this morning was cold and did my normal thing and it was fine for another 50 mile trip to work,,so i dont understand why those summit coils did that but im a happy camper,,now i can move on to shocks and brakes
 

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