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  #16  
Old August 6th, 2018, 11:35
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alexgalexg alexgalexg is offline
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Over my head in problems and need help

Ok so took a trip to the shop today. That bunch of codes was because the dude didnt plug the reader in correctly. Here is what I had the shop check.
Wiring
Compression
Upstream o2
All data from obd II

They are as baffled as I am as to why it pings without premium and has had 2 cracked heads in 2 years 25,000 miles. They said it's running perfectly. They did notice the compression was a hair high (in the attached photo) but that is likely due to the new head in December. And the numbers are not high enough to really be causing any issues.
They also said even if the timing jumped a tooth it would be running like crap.

Any other tips? Really worried about this thing blowing a head in the winter... dont have a garage

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  #17  
Old August 6th, 2018, 12:15
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four_shot four_shot is offline
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Re: Over my head in problems and need help

Only thing I can think of is there is excess carbon build up on the pistons.

The only other option is either the block or the head was decked too much and a shim or thicker head gasket is required.

Just spit balling.
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  #18  
Old August 6th, 2018, 12:55
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Re: Over my head in problems and need help

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Originally Posted by four_shot View Post
Only thing I can think of is there is excess carbon build up on the pistons.

The only other option is either the block or the head was decked too much and a shim or thicker head gasket is required.

Just spit balling.
Pistons are very clean. Checked on that in December. What little carbon there was I used seafoam and scrubbed off

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  #19  
Old August 6th, 2018, 14:21
RCP Phx RCP Phx is offline
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Re: Over my head in problems and need help

Those numbers may be on the "higher" end, but by no means "high".
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  #20  
Old August 6th, 2018, 14:23
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Re: Over my head in problems and need help

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Originally Posted by RCP Phx View Post
Those numbers may be on the "higher" end, but by no means "high".
I'd check the timing chain so see if maybe it's just a bit loose (maybe a quarter of a tooth off) but that's so much work for possibly nothing wrong I really dont intend to do so.

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  #21  
Old August 6th, 2018, 17:08
trippled trippled is offline
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Re: Over my head in problems and need help

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Originally Posted by RCP Phx View Post
Those numbers may be on the "higher" end, but by no means "high".
Agreed. I just checked a 04 4.0. all 160-155.

Have you checked the actual ignition timing with a timing light versus the PCM desired timing (scan tool)? If for some reason it's too advanced it can ping.
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  #22  
Old August 6th, 2018, 17:19
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Re: Over my head in problems and need help

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Agreed. I just checked a 04 4.0. all 160-155.

Have you checked the actual ignition timing with a timing light versus the PCM desired timing (scan tool)? If for some reason it's too advanced it can ping.
I unfortunately do not have access to this tool. I would be interested in trying to save this engine since most of it was replaced in December of this past year

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  #23  
Old August 9th, 2018, 14:40
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Over my head in problems and need help

Sits around 10-12 at idle and I cant see what marks it goes up to when you rev it up but it goes to the same spot and stays there

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  #24  
Old August 9th, 2018, 16:17
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Over my head in problems and need help

I forgot to mention I'm talking about timing in the last one. Used a timing light

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  #25  
Old August 10th, 2018, 18:04
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Over my head in problems and need help

I couldn't compare the timing from the timing light to the timing on front the computer because my live feed on my reader is too slow to really tell me if they are matching. I was hoping someone here would tell me if these are good numbers

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  #26  
Old August 12th, 2018, 11:01
CJR CJR is offline
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Re: Over my head in problems and need help

Re: Cracked Heads

Many years ago I went through cracked heads on a four banger. I was informed by a number of engine shops that it was a chronic problem with this brand of vehicle. I pulled the cracked head and checked it out on my bench. I concluded the ports in the head were undersized on purpose to reduce the flow and run hotter so as to improve emissions. The reduced flow through the head allowed carbon to build-up in the ports. As carbon built-up in the ports, the head started to run hotter and eventually the head would crack. My solution was to mildly port the head to improve flow. Problem solved and I never cracked another head in about 250,000 miles.

Pinging/pre-ignition can also be caused by carbon build-up in the head's combustion chamber. The fact that there is a carbon build-up in a particular part of the combustion chamber indicates a " flow dead-zone", i.e. poor flow through the combustion chamber. A mild porting improves flow during the valve overlap duration (i.e. when both intake and exhaust valves are open).

Hope this helps.

Best regards,

CJR
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  #27  
Old August 12th, 2018, 18:59
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Re: Over my head in problems and need help

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Re: Cracked Heads

Many years ago I went through cracked heads on a four banger. I was informed by a number of engine shops that it was a chronic problem with this brand of vehicle. I pulled the cracked head and checked it out on my bench. I concluded the ports in the head were undersized on purpose to reduce the flow and run hotter so as to improve emissions. The reduced flow through the head allowed carbon to build-up in the ports. As carbon built-up in the ports, the head started to run hotter and eventually the head would crack. My solution was to mildly port the head to improve flow. Problem solved and I never cracked another head in about 250,000 miles.

Pinging/pre-ignition can also be caused by carbon build-up in the head's combustion chamber. The fact that there is a carbon build-up in a particular part of the combustion chamber indicates a " flow dead-zone", i.e. poor flow through the combustion chamber. A mild porting improves flow during the valve overlap duration (i.e. when both intake and exhaust valves are open).

Hope this helps.

Best regards,

CJR
That is an interesting experiance. I was sure to get an 0630 head do I don't think the flow is restricted but it's definitely something to keep in mind.
Thank you

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  #28  
Old August 13th, 2018, 16:32
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Over my head in problems and need help

What do you guys think about seafoam in the crank case. My top end and pistons are clean but I know the previous owner did not change the oil often. When I put a new head on originally the valve train was covered in thick sludge. So maybe buildup in the crank case is the issue

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  #29  
Old August 13th, 2018, 17:25
trippled trippled is offline
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Re: Over my head in problems and need help

What plugs are you using? As in exactly what part number is on the plugs?
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  #30  
Old August 13th, 2018, 19:11
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Re: Over my head in problems and need help

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What plugs are you using? As in exactly what part number is on the plugs?
I will have to get back to you on the part number. But they are the standard ngk copper plugs. Everyone says that's what the 4.0 runs best on so that's what I use

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