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post #1 of 11 (permalink) Old 10-11-2018, 10:09 AM Thread Starter
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Question Crank, No Start, Very Low Compression

Hi there! I apologize for skimming over a lot of details, but the tl;dr is that my engine had been suffering from intermittent misfires and low power and surging conditions for a few months prior to completely failing, particularly after high humidity and rain. With this in mind, I replaced the COPs and spark plugs, as well as installing extra grounding points as suggested in old posts on this forum, and also installed a new battery. All of which were kind of due for replacement anyway.

However, none of this aided my issue. Skipping around a bit in the details, I eventually did a compression test of all cylinders, admittedly much later in the diagnostic process than I should have. I found all cylinders were between 70 PSI at worst, and about 145 PSI at best. From what I could gather here on the forum, the factory spec is about 200 PSI, +/- 10 PSI. So obviously I have a dead engine in need of major repairs.

My questions then are:
  • Is it worthwhile to try to rebuild the engine? I assume if I'm going to undertake that process, it's really best to rebuild it from the block up, rather than trying to get by with only cylinder honing, new piston rings, and new crank shaft and piston bearings, assuming the heads don't show any major signs of wear or failure. I can do most labor aside from block and head machining, though I would probably need to purchase a handful of rebuild-specific tools. Hoping I could rent or borrow an engine hoist and electric drill (for cylinder hone), among other tools.
  • Would it be smarter to try to source a junkyard engine, either to swap completely, as-is, or alternatively, to combine good parts from both engines?
  • Or should I just scrap the vehicle? As-is, towed to a junkyard for whatever deal I might be able to get, $250 at most if I'm lucky (but more likely $100-$150)? Or instead trying to part the vehicle out? Though I doubt that there's much more to be gained from individual parting, considering it's not a particularly common and in-demand vehicle.

A few more details: The vehicle is largely in solid condition, with minor body panel rust in one of the quarter panels. Interior's main blemish is a drooping headliner that needs re-glued or reupholstered. Also missing the dash console lid due to broken hinges on the original part, which I still have. However, moving back to the exterior, the vehicle absolutely needs 4x tires, and ideally a FR wheel bearing replacement and alignment to go with new tires. As well, the brakes all around could probably use a refresh, and a fluid flush at minimum. Rear calipers likely need rebuilt due to poor rotor contact. Would also maybe be a good idea to replace the rubber brake lines in that process, just as preventative maintenance.

Engine has around 137k miles, iirc. Admittedly I wasn't too good with oil maintenance due to an oil pan leak (which I also fixed during above troubleshooting) and I did take the vehicle to a few SCCA autocross events. There was metallic flaking in the drained oil. So certainly the piston rings and/or cylinder sleeves are bad, but hopefully bearings aren't excessively worn (a moot point if I rebuild, but good to know for failure-mode diagnostics). I suppose now that I think of it, there must have been light blow-by which was a cause of minor oil loss from the front-bank crankcase vent.

Last edited by WhiteVaille; 10-11-2018 at 12:57 PM. Reason: Typos
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post #2 of 11 (permalink) Old 10-11-2018, 10:33 AM Thread Starter
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So, expanding a bit more, these issues happened back around November 10th, 2017, the worst as I was commuting home from university in Athens, OH back to Lancaster, OH. A bit of a hilly commute, which of course exacerbated the low power and surging issue. Unfortunately I had to drop out of the semester as I wasn't able to complete the final month or so of classes, due to lack of transportation and a ~50 mile commute. I thought I would try to wait until the following spring semester to repair my vehicle using my student loan disbursement. Unfortunately again, due to some course hour conflicts, I didn't receive my disbursement until a week in to the semester. On the short notice, I tried searching for a used vehicle on Craigslist, but with a budget of only $2000 which needed to cover the car + tax + registration + repairs + gas, and needing a car that needed to be ready to go the next day, I wasn't able to find anything attractive. So instead I tried putting the money in to some cheap, basic diagnostic and repair tools on Amazon, plus parts for the car, etcetera. All of this of course taking more time in to my classes.

End result is I had to withdraw again due to still having a dead vehicle, already closing on the first exam of the semester, and thus owe the university about two and a half times my disbursement amount after fees and interest (which is still capitalizing, of course). And I don't have any source of income since then and at present.

I'm not trying to leave my sob story (tsk, and in my second/third post on the forum, at that). Just trying to figure out what to do with this dead vehicle in my driveway - whether I should cut my losses, sell it for scrap money, hold on to the parts I purchased and move on. Or, I feel like in the money I would spend trying to find another cheapshit beater that runs, plus paying tax and registration and such, that I might be better off spending that on my current chassis. I don't have experience with machine shops, and I've never parted out an engine rebuild, so I don't really know what that could cost. Kind of a wild guess, but I would think I should be able to rebuild the engine, replace the tires and brakes, get an alignment, etcetera, for around $2000? Maybe closer to $1500? Also keeping in mind that I'll need to purchase valve spring compressor, valve lapper, cylinder hone, electric drill, engine hoist, blah blah blah.

Money that I don't have, but if I did have, doesn't seem like I could get a reliable vehicle for that cost.

....Anyway. I don't really know. I don't have a plan. Doesn't help that I live in a commuter town with negligible public transportation infrastructure. I'm just mulling over hypothetical scenarios here. Input from more experienced gearheads would be greatly appreciated.
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post #3 of 11 (permalink) Old 10-11-2018, 10:48 AM Thread Starter
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Not sure what value I would glean from this right now, but should I bother removing the heads to see the state of the cylinder walls and combustion chamber? I don't really know if that would make much difference in saving costs, if the walls aren't gouged. Suppose it could mean they could be bored over instead of re-sleeving. But anyway, I obviously don't have a torque plate, and I don't currently own micrometers, bore gauges, or even a Vernier caliper to check the cylinder IDs / piston ODs.
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post #4 of 11 (permalink) Old 10-11-2018, 11:11 AM
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@WhiteVaille I see that you mention that you had a misfire for months before all of this. I hate to say this but what probably happened was catalytic converter failure because of the misfire which in short caused your engine to essentially eat itself alive. I would assume your cylinder walls and piston rings are definitely destroyed and possibly your heads. If you have the know how, the time and the tools you could find a used engine somewhere and swap it keep in mind you can use the 3.0l out of the ford fusion as well you just have to swap some of the external components like the valve covers, I think the timing cover if you search this forum enough there are lots of people that have done it. Just saw your first post cat failure was a MAJOR problem on the 03-05s

Also I see you're from Ohio so, hi from North Canton

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Last edited by bluedevil6; 10-11-2018 at 11:22 AM.
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post #5 of 11 (permalink) Old 10-11-2018, 11:16 AM
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It could be a head gasket.
Have you been losing coolant?


Or it could be an issue with the method used to do the compression test.
Double check the procedure for using your gauge.


Has the car been using oil?
If the cylinder walls were scored you would have a blue cloud following you.
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post #6 of 11 (permalink) Old 10-11-2018, 11:25 AM Thread Starter
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Yeah, cats were/are a concern. I had two replaced back in 2014, so I would like to hope that those are still in serviceable condition. In removing them to service the oil pan, I didn't notice any rattling whatsoever. Heat shield of the front bank pre-cat easily fell off due to corrosion, revealing a dark, heat-stressed circle in the middle of the bottom side. But I don't really have a good way to inspect them beyond that. Suppose I could try removing them and flushing them with water (youtu.be/6qSMgj5_djE), but I'm not sure that that would really tell me how clogged or open they are. (Also fwiw, our home's exterior spigots are all seized, so I'd have to run jugs of water back and forth from the kitchen. Doable but not worthwhile.)

I do have an IR thermal gun, but that's not too helpful if I can't get the engine running to check temperatures fore and aft of the converter.
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post #7 of 11 (permalink) Old 10-11-2018, 11:33 AM Thread Starter
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Quote:
Originally Posted by grunt1981 View Post
It could be a head gasket.
Have you been losing coolant?


Or it could be an issue with the method used to do the compression test.
Double check the procedure for using your gauge.


Has the car been using oil?
If the cylinder walls were scored you would have a blue cloud following you.
Unlikely. Never noticed any coolant loss, nor mixed fluids in their respective reservoirs.

I don't know about my specific gauge's recommended procedures? I just removed all spark plugs and check the compression one cylinder at a time by cranking the engine with the starter, for maybe a dozen revolutions at most. I replaced the oil pan gasket and refilled the engine with oil prior to this in hopes I'd manage to get a wet test instead of a dry test, though the engine had been sitting for quite some time before I got around to this.

(Tried removing the fuel pump relay, but the car won't crank without it installed. Probably should have unplugged all the fuel injector harnesses, but meh.)

As for burning oil, that's one thing that I never really noticed, but was constantly paranoid about. It would sometimes expel quite a bit of condensate when it was cold out, but I never noticed smells of oil nor blue smoke. So I think it was just leaking from the oil pan and front crankcase vent. Possibly also the camshaft seal at the rear of the engine (by the transmission) that drives the oil pump, but I haven't been able to confirm that yet. Also can't confirm there aren't other minor leaks towards the front of the engine (pulley side), but I believe I repaired the worst of it.
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post #8 of 11 (permalink) Old 10-11-2018, 11:41 AM
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I don't think anyone has really come up with a sure-fire way to inspect the cats short of cutting them open. I have read of some people using a borescope through the O2 socket.

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post #9 of 11 (permalink) Old 10-11-2018, 12:05 PM Thread Starter
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Cats are a relatively low priority, though. You can run the car without them if you have to. Emissions won't be happy, so you'll be stuck with a CEL. I did often have a low-efficiency code, on that note. But yeah, that wouldn't cause it to not run outright.
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post #10 of 11 (permalink) Old 10-11-2018, 12:14 PM
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Rebuilding and engine can be very expensive, you never know what you are going to find and many times those additional items come out after you already spent good money on it.


If you have the tools and knowledge, remove the valve cover,check that all valves are working and closing properly, look for something that could explain the low compression. If you find nothing, you could remove the head and swap the gasket (although there is no coolant/oil contamination). That would be the most I would spend on it.


I would never spent $2k on a $2k vehicle, even more when you do not know if it is going to run right at the end. Your 6 needs a lot of work from what you’ve described.


You need a reliable vehicle if you are commuting 50miles/day. If the head gasket doesn’t do the trick, cut your losses and get a basic but newer low mileage car that runs good. Look for those that don’t haveAC or power windows, they are cheap because nobody wants them but not because they are beat or have something wrong.

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Last edited by jman1200; 10-11-2018 at 12:17 PM.
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