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Discussion Starter · #44 ·
I haven’t done the reflash yet they just went away and never came back very strange
Ah okay, yes thats stange, anyways had some luck today, did a leak down test at a mechanic i was supposed to go to before but ended up going to a different one that day. So he did a leak down test and the compressor was showing 65 psi i believe if im correct? There was alot of air coming out the intake manifold oil fill hole. He said my valve seals are bad or its come loose, so hes going to pull the heads off and let me know if there is anything else and how many valve stem seals are bad or have come loose. Now i believe this is a manufacturing defect for these seals to go bad or come loose? Its all because of heat, racing and driving it aggressively which i dont do, i like to cruise and drive it hard here and there sometimes not regularly or frequently like some previous owner did perhaps. It gets pretty bizarre here in Saudi Arabia in the summers and some previous owner probably raced it around alot and at high RPMs causing the valves to rattle a lot and wear out the seals.

Having said all that i think im going to put in a lower thermostat at 180 for cooler engine operations after fixing my valve seals.

My issue does not seem to be the PCM, even tho i got a new one, better to have a new one now according to the high mileage i have.
 

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Ah okay, yes thats stange, anyways had some luck today, did a leak down test at a mechanic i was supposed to go to before but ended up going to a different one that day. So he did a leak down test and the compressor was showing 65 psi i believe if im correct? There was alot of air coming out the intake manifold oil fill hole. He said my valve seals are bad or its come loose, so hes going to pull the heads off and let me know if there is anything else and how many valve stem seals are bad or have come loose. Now i believe this is a manufacturing defect for these seals to go bad or come loose? Its all because of heat, racing and driving it aggressively which i dont do, i like to cruise and drive it hard here and there sometimes not regularly or frequently like some previous owner did perhaps. It gets pretty bizarre here in Saudi Arabia in the summers and some previous owner probably raced it around alot and at high RPMs causing the valves to rattle a lot and wear out the seals.

Having said all that i think im going to put in a lower thermostat at 180 for cooler engine operations after fixing my valve seals.

My issue does not seem to be the PCM, even tho i got a new one, better to have a new one now according to the high mileage i have.
It was weird that it just went away and valve seals seem like a possibility if your car is making a tapping noise (could be lifters) does your car blow blue smoke in the morning ? It’s possible they have came lose or cracked since they breakdown over time. Let me know what he saids. I have the 180 degree thermostat no tune so while idilimg it doesn’t make any difference for me but highway driving or just city driving makes a huge difference in power and response time. I usally sit at 185 degrees when driving which is nice.
 

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Discussion Starter · #47 · (Edited)
update

mechanic did compression test on all cylinders and leak down test also and no leaks anywhere but cylinder 5 was at 120 psi and that was lower than the rest of the cylinders.

He used his stethoscope on cylinder 5 and its ticking, my lifters are bad there and that might be the cause. The car has high mileage so it makes sense!

So off i go and get new lifter sets and new cam also, might as well do all in one go now.
 

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I kinda doubt you have a bad lifter. Not a known issue in the pre-eagle engines. Not to say it can't happen, but I'd love to see pictures when the repair is done.

Sent from my SM-G988U using Tapatalk
 

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Discussion Starter · #51 ·
Bad lifter is possible but unlikely symptom of the issue that it is causing. Do you have a picture of the lifter ? it could make sense if it messed up your cam
I dont have a pic of it unfortunately as the mechanic didnt open up the valve covers to check. I can open up the valve covers, remove them and check all my lifters.

Was thinking maybe a bottle of lucas oil additive might help or a can of BG44K in the fuel tank, to clean up the valves if it does that.

Oh and i did put my new PCM yesterday and it doesnt seem to be misfiring after 15 mins of driving. Maybe its just the start phase and will happen again i dont know, lets see when i go and start the car today.
 

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It's more than that. You would have to pull the heads to look at the Lifters.
I think you are on the right track with the pcm.

Sent from my SM-G988U using Tapatalk
 

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Discussion Starter · #53 ·
It's more than that. You would have to pull the heads to look at the Lifters.
I think you are on the right track with the pcm.

Sent from my SM-G988U using Tapatalk
New PCM resolved the P0300 issue, now getting a P0420 and P0430 code, my cats are new as in hi-flow cats i installed 2 weeks ago so could that be it ? I did turn the rear 02 sensors off with my old PCM so is the new PCM still reading that?
 

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Yes. Turn the downstream sensors off and/or run a fooler.

Sent from my SM-G988U using Tapatalk
 

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Discussion Starter · #57 ·
P0420 and P0430 went away by itself, I believe PCM was trying to get use to the hi-flow cats threshold, not sure but it’s no longer there and I got a check gas cap text on the cluster today, was raining hard maybe some water on it o-ring caused it but will get it replaced as it’s never been replaced before and that gas cap text also went away by itself.

check engine light now also shows when turning on electrics with the other dummy lights. Weird right? But I’m glad its all sorted now! Just want to get my self some oil catch can hoses and bracket soon so I can get that installed.

want to thank everyone who helped me in this journey and it definitely has been stressing big time!

thanks again 🙏🏼
 

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Discussion Starter · #58 ·
I kinda doubt you have a bad lifter. Not a known issue in the pre-eagle engines. Not to say it can't happen, but I'd love to see pictures when the repair is done.

Sent from my SM-G988U using Tapatalk
you were right lifters were not bad at all, it was a bad PCM heater circuit driver. Used the HP scanner software to read the data and bank 2 sensor 1 is alive again.

The lifter kind sound I and the mechanic were hearing from the left front fender well (as that’s where we put our ear lol) was coming from the mid magnaflow muffler, as it’s case has several pin hole leaks across the side and from the exit too, I will have mid Muffler replaced soon or maybe a nice corsa extreme cat-back system! Love the sound of those bad boys….
 

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Discussion Starter · #59 ·
Did your idling issue resolve now ? How loud are the high flow cats ?
how loud are the hi-flow cats - they sound great! Not very loud or very Quiet, it’s loud but loud in a good way, I have magnaflow mid muffler and magnaflows at the rears too so it sounds nice and deep and when WOT it’s an animal.

before I had gutted cats and they sound almost the same however I prefer the high flow cats.
 

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how loud are the hi-flow cats - they sound great! Not very loud or very Quiet, it’s loud but loud in a good way, I have magnaflow mid muffler and magnaflows at the rears too so it sounds nice and deep and when WOT it’s an animal.

before I had gutted cats and they sound almost the same however I prefer the high flow cats.
I might have to get some !! I just have a cut off with no res or muffler. UPDATE alternator took a shit last night had to drive car home but cars idle was smoother and trans shift so much more smoothly and no hesitation or anything drove better then when the alternator was charging. Hopefully it will fix my issue for me on my rpm stumble and some drivability issues
 
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