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Compression Check Measurements

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Old 01-27-2014, 11:47 AM
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Compression Check Measurements

I got my compression checked today and these are the results..... The dealership told me that it's busted but I want to get yalls opinion.
No.1 No.2
Ports 636 657
642 661
647 622
These are the measurements at 205 rpm. What do you guys think?
Old 01-27-2014, 11:49 AM
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Your starter is nearly dead, but those numbers are still passing when normalized to 250rpm. It's wearing, but it is still acceptable numbers and should still last a while.

Old 01-27-2014, 11:57 AM
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You are within spec when normalized to your altitude. Time for a new starter.
Old 01-27-2014, 12:02 PM
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Yeah the starter seems to be getting weak. The car is at around 92,000 miles. Not too bad i guess. They straight up told me to ditch it. What would you recommend at this point? Thank you for your response by the way. I appreciate it.
Old 01-27-2014, 12:11 PM
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The chart that they printed out says Compen. (250 RPM)
[U]No. 1[U] No.2
738.41 759.41
744.41 763.41
749.41 724.41
I assume these would be close to accurate results had the test been run at 250 RPM. I figured everything was in spec but they told me otherwise. Probably trying to make me blow more money....
Old 01-27-2014, 12:26 PM
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Mazmart.com for the starter. Best price for the S1, and I think best price for the S2 starter too. Go for the S2 starter if you can afford it, it's rather beastly with cranking speed.
Old 01-27-2014, 12:31 PM
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Yes sir! I'll check it out! As for my compression though. About how long do you think my engine will hold up? I do all of the proper procedures to keep it healthy and i run 10w-30 oil but on my last change i went up to 10w-40. plugs and coils are only a year old.
Old 01-27-2014, 12:34 PM
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When i turn my key off it makes a loud kind of screeching noise kind of like a rusty fan motor. i think its the solenoid on my starter.
Old 01-27-2014, 12:47 PM
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Your starter only has power with the key held to "start". Once you relax the key to "On" and the engine is running, the starter doesn't get any power until you move the key to "start" again. The screeching is something else, possibly an accessory belt?


I'd say you probably have at least 30k more in that engine, provided you maintain the cooling and oil systems properly. Start thinking about replacing cooling system parts that are still original, they start failing around 100-110k, and if one fails it will take your motor with it. Mazmart has great prices on every piece, and I think you can replace all the hoses, the thermostat, coolant bottle, and radiator for around $500-$600 in parts from them. 30k is a low estimate though, you could easily have far more.
Old 01-27-2014, 12:50 PM
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if i were to have the apex seals replaced with the compression the way it is would that be a smart thing to do? i imagine that the seals have just worn down a bit and that replacing them would increase my compression. Since you guys said the my compression meets spec, i would think that the housings are in decent shape. am i wrong?
Old 01-27-2014, 12:51 PM
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You are talking a rebuild. Yes, a rebuild with a healthy engine would generally be cheaper than a rebuild with a blown engine, but it still won't be cheap enough to really justify rebuilding ahead of time. Chances are you would still have to go with new bearings and new housings. If you have the money for a rebuild now and want to "be safe", then a better idea would be to buy a known good engine and keep it in storage until you need it.
Old 01-27-2014, 12:52 PM
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Originally Posted by Blubeasty22
Yeah the starter seems to be getting weak. The car is at around 92,000 miles. Not too bad i guess. They straight up told me to ditch it. What would you recommend at this point? Thank you for your response by the way. I appreciate it.
call the service manager and tell him to send their tech back to school, if they don't know what they are doing then they are basically stealing money from customers. if they don't know then they may possibly do the same to the next 8 owner who passes through, if they realize the liability then they may correct their mistakes.

Last edited by Karack; 01-27-2014 at 12:55 PM.
Old 01-27-2014, 01:26 PM
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Originally Posted by RIWWP
Your starter only has power with the key held to "start". Once you relax the key to "On" and the engine is running, the starter doesn't get any power until you move the key to "start" again. The screeching is something else, possibly an accessory belt?


I'd say you probably have at least 30k more in that engine, provided you maintain the cooling and oil systems properly. Start thinking about replacing cooling system parts that are still original, they start failing around 100-110k, and if one fails it will take your motor with it. Mazmart has great prices on every piece, and I think you can replace all the hoses, the thermostat, coolant bottle, and radiator for around $500-$600 in parts from them. 30k is a low estimate though, you could easily have far more.
Yeah when I turn the key from start to off it makes that noise. I don't know why it sounds like its coming from there but i could be wrong.
I need to replace the radiator ASAP. Its leaking like crazy and I check it before each drive but its extremely inconvenient. I found a radiator new for $117 so ill probably get it and replace it either this week or next.
Old 01-27-2014, 01:33 PM
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If it's mishimoto, pass, they are generally poor.

Mazmart sells the OE radiator for $150. If you have the radiator out, consider replacing more of the cooling system, since you will have removed much of it anyway. Thermostat and water pump are about the only 2 items that wouldn't have been removed. Half the cooling lines and the coolant bottle will be out too, and replacing the coolant bottle often results in a broken radiator inlet nipple.

Coolant bottle is $130 with cap and replacement short hose
Hose kit is $200 i think. If you don't replace the lines, make sure you clean each of them thoroughly inside and out.
Old 01-27-2014, 01:50 PM
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Originally Posted by RIWWP
You are talking a rebuild. Yes, a rebuild with a healthy engine would generally be cheaper than a rebuild with a blown engine, but it still won't be cheap enough to really justify rebuilding ahead of time. Chances are you would still have to go with new bearings and new housings. If you have the money for a rebuild now and want to "be safe", then a better idea would be to buy a known good engine and keep it in storage until you need it.
Yeah i wouldnt have the money to have that done. I'm only 19. I payed for the car myself done all of the maintenance on it except for the comp check and clutch pedal replacement. If i had the time, tools, place, and money i would gladly overhaul it myself but i'm lacking all of those things.
Old 01-27-2014, 01:56 PM
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Originally Posted by Karack
call the service manager and tell him to send their tech back to school, if they don't know what they are doing then they are basically stealing money from customers. if they don't know then they may possibly do the same to the next 8 owner who passes through, if they realize the liability then they may correct their mistakes.
Haha i'm tempted to. He didnt even put all of the spark plug wires on all the way. i was wondering why it misfired so bad when i left. i would never take my car to a shop for any reason at all unless there is something that i absolutely cannot do by myself. Getting the comp checked is a perfect example. Its a good thing i was cautious and had them print off the result for me otherwise i would be thinking i needed a new engine at this point.
Old 01-27-2014, 02:05 PM
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Originally Posted by RIWWP
If it's mishimoto, pass, they are generally poor.

Mazmart sells the OE radiator for $150. If you have the radiator out, consider replacing more of the cooling system, since you will have removed much of it anyway. Thermostat and water pump are about the only 2 items that wouldn't have been removed. Half the cooling lines and the coolant bottle will be out too, and replacing the coolant bottle often results in a broken radiator inlet nipple.

Coolant bottle is $130 with cap and replacement short hose
Hose kit is $200 i think. If you don't replace the lines, make sure you clean each of them thoroughly inside and out.
Awesome! Thank you for the advice. It truly helps me out a lot. My sensor in the reservoir keeps going off and on. ive cleaned it out a bunch of times to keep the float from sticking but the sensor still goes off.
Old 01-28-2014, 11:56 AM
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Originally Posted by Blubeasty22
Haha i'm tempted to. He didnt even put all of the spark plug wires on all the way. i was wondering why it misfired so bad when i left. i would never take my car to a shop for any reason at all unless there is something that i absolutely cannot do by myself. Getting the comp checked is a perfect example. Its a good thing i was cautious and had them print off the result for me otherwise i would be thinking i needed a new engine at this point.
way to be an enabler.

this is partly what is wrong with the world today, companies know they can get away with it so they do.
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