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No compression in cylinder!

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90clipseturbs

Probationary Member
19
2
Feb 2, 2007
Casa grande, Arizona
i went to get my dsm smog tested, love living in CA!, and my car failed miserabily, its now considered a gross pollutant by the state and it must be fixed immediatley so i can keep the car or else i must get rid of it, and i dont want to let it go:( so i got the car a diagnostic and they found out that i was getting no comperssion at all in my first cylinder, the mechanic who did the test said it would cost alot to fix the problem, probably more than i want to spend to keep it and since it has almost 250k on the engine, but it runs great and pulls strong, it would not be worht the fix. I really really dont want to give the car away to the state for their $1000 offer to take it off the road but i am in college and dont have alot to spend to fix it, since i was talking to a mechannic i am hoping he was just trying to get money out of me so i am hoping that there is a not so expensive way to fix it, and also i found out i qualify for 500$$ to help fix the problem, is their a way to fix it for about 500 or a little more dollars...? thank you for any responces to help me, the thought of losing my car makes me feel sick:barf:
 
what was the compression in all of the cyl ?

Did he do a leak down test also ? If so what was the results ?


depending on what the problem is , is going to tell you how much it's going to cost

If it needs ring's they are around $118 for a set of 4
If the block is not scared up you may be able to get away with just honing it out

And while you got the pistons out would be a good idea to replace all the bearings which is under $100 also

Replace the head gasket with a Mitsu MLS under $100

I don't know how up to date your timing belt is and that depends also

As you can see parts are not going to cost you much but the labor is going to be high , I can see you spending upwards of $1500 if you can find someone thats not going to rip you off sense you don't know much about it
 
What were the compression numbers across the board? Did they do a wet compression test as well as a dry? If so, were the results of the wet test any higher than the results of the dry test? If the wet test netted higher compression, your piston rings might need to be replaced. Also, did they do a leak-down test? If so, what did they find?

If you do need to replace the piston rings, you'll have to service the block in some way. As mentioned, you might be able to get away with honing, but my guess is with 250k miles you motor will have susbantial wear. You will have to have a machine shop bore out the block pending the results of the cylinders' out-of-round and taper.
 
not sure what the compression was in the other cylinders but he said they were normal. (except the one with none of course) dont think he did a leak test, and he said when he looked in the cylinder he said it looked like the piston had some damage done to it like it hit the spark plug or something. thats all i am aware of, i jsut not sure what to do at this point with it because if i cant get it fixed i'd like to get it to someone that can because i just cant deal with that right now nor can i deal with the thought of my car being crushed!
 
i such a newbie i dont know what the difference between wet and dry test, i know he tested it running and also not running and the #1 cylinder showed 0 compession during both and he told me the others were normal during both, no leak test though... what does a leak test show and is their a way i could do a leak test...
 
i such a newbie i dont know what the difference between wet and dry test, i know he tested it running and also not running and the #1 cylinder showed 0 compession during both and he told me the others were normal during both, no leak test though... what does a leak test show and is their a way i could do a leak test...

A compression test is basically diagnosing an engine's ability to pump and compress air. A dry compression test is a fairly straight forward procedure. A good "how to" link with step-by-step instructions and pictures can be found here.

Basically, a wet compression test is the same as the process shown in the above link. However, in a wet test you add about one tablespoon of oil to the cylinder. The added oil helps worn rings seal with the cylinder wall. If the numbers of your wet test closely resemble the numbers in your dry test, then you rings might not be the culprit of your low compression. However, if you find that compression is noticeably increased with the wet test, your piston rings (or cylinder wall) might be worn to where you are not getting a good seal in the cylinder. Hence the low compression.

Finding that cylinder #1 records absolutely 0 compression while the other cylinders are within spec sounds a little odd to me. Do you know or could you find out what the compression numbers were across the board? I understand that you might not be mechanically inclined, but it might be a good idea if you did another compression test yourself... if at all possible. The link I posted above is very detailed and is even vehicle specific (test done on 1g DSM!). If you could do a compression test or at least find out the results the mechanic recorded (wet & dry if possible) that would be a good start.
 
I would be a little skeptical of what you are being told. In your opening post you state "it runs great and pulls strong,.." That is not at all consistent with having one cylinder basically not functioning.

I would get a second opinion or better yet buy a compression tester and do it yourself. You can get the tester for as little as $15 online and you will have it forever. Follow the instructions given in the link in post #6. If you have any questions I/we would be happy to help you out. Trust me, it's really not hard at all as long as you can remove/replace your sparkplugs.:thumb:

Edit: Sorry Zmann42087, I didn't see that you had already suggested this in the last part of your post until right now.
 
thanks alot for the input you all!! I will go buy a compression tester tomarrow and give doing those tests a shot with, that link you gave me i better be able to figure out how to do it myself! so i will try to perform those tests tomarow when i have a chance and i will go ahead and post the numbers i get for a wet and dry test and let you guys know how it goes. thank you all so much in helping me save my DSM's life!!!!
 
i did the compression test and here are the results for the wet and dry test, going from cylinders left to right:
dry: #1- 155 #2-140 #3-130 #4-30

wet: #1-175 #2-180 #3-170 #4-35

so to me it seems i have a bad cylinder like he said, what else could be the cause of this and what could i do????
 
Have you cheked the coolant in your reservoir? If it is brownish or milky, you may very have well blown a HG, but all of your #'s are good on your other cylenders. Check the torque on the head and post back.
 
oh man, i think my problem just got worse!!!!! my brother was helping me with the tests and when putting the spark plug wires back on i think the order got confused because when i tried to start it back up we heard a loud pop! sound from the engine, what could putting them in the wrong order cause my car to not start!!!! i'll check the coolant here in about 5 minutes also.
 
oh man, i think my problem just got worse!!!!! my brother was helping me with the tests and when putting the spark plug wires back on i think the order got confused because when i tried to start it back up we heard a loud pop! sound from the engine, what could putting them in the wrong order cause my car to not start!!!! i'll check the coolant here in about 5 minutes also.

Sounds like you mixed up spark plug wires when you put them back in the cylinders. The firing order for our cars in 1-3-4-2. Carefully put them in the right order now.
 
so by me doing that it didnt do any harm to my car? if not that is a huge relief, (boy was my face red), oh yea my coolant is looking a little brown and thick, you think its a blown head gasket or could it just be dirty???
 
The low compression in cylinder 4 (actually the one on the far right when you're looking at the engine is #1) may be caused by the valves not seating properly or a blown head gasket as mentioned above. You can look for coolant in oil and vice versa which would indicate the HG. But a leakdown test would be the most accurate way to locate the problem. You can buy the testers but you may want to consider having this one done at a shop.

If you still haven't figured out the correct plug wire order as it relates between coils and cylinders let us know. I think I have seen a picture somewhere on the forums showing this.
It may be easier than trying to explain in words. Also consider investing in a repair manual. Every DSM owner NEEDS one!:)
 
hey Zmann42087, did you see my post with one of my cylinders only putting out 30 dry and 35 wet psi, since the oil didnt do much difference what beside the rings would be the cause and fixes to my problem, thanks for helping me out!
 
A leak down tester will tell you % of leak down and where you are losing the compression. But you already know you have very little compression in #4. You can just put compressed air into #4 (with both valves closed) and see where you are losing it, percentage dosen't matter at this point.
 
hey Zmann42087, did you see my post with one of my cylinders only putting out 30 dry and 35 wet psi, since the oil didnt do much difference what beside the rings would be the cause and fixes to my problem, thanks for helping me out!

Looking at your numbers from the wet and dry compression test, I would say your piston rings are worn (you can see the numbers go up across the board on the wet test). However, I really doubt that is the only problem with the cylinder that posted 30 and 35 psi on the compression test... I'd say there is something else. Now from my experience, it is usually two adjacent cylinders with low compression that indicates a blown head gasket. That said, a BH could still very well be your problem, but I'd guess it is something like the valves not seating properly as Romeen suggested. Of course this is only my guess after looking at your compression test results.

The way to precisely locate where compression is being lost is to perform a cylinder leakage test or "leak down test". A leak down test is more involved than a compression test. Considering you are still pretty new to all of this, it might be best to take it to a repair shop to have the test done.

Also, in case you haven't been able to get the firing order cleared up here is a diagram that might help.

You must be logged in to view this image or video.
 
Wow! you guys are so much help! i just got back from purchasing a repair manual(should of done first off) one more quick question, on the cap, the top is #3 and the bottom is #4, right? and looking straight at it, which # is on left and the right, i apoligize for my probably seriously easy questions, i am just really afraid to make a mistake. with that asked i going to see about getting a leak test somewhere and take a look at my head gasket, might not happen tomarrow though, school and work, but as soon as i do i'll let you know my results. once again you all are a great source of help and i cant thank you enough!!!!
 
Did you get a chance to take the car to a shop yet? What did the leak down test find? Let us know how things turn out...
 
Have you pulled the valve cover to check the valve train? Something as simple as a broken valve spring could be the issue here. When I was in auto tech last year during high school we had 2 trucks come into the shop with no compression. 1 was a late model f-150 and 1 was a late model chevy silverado. Both trucks had 1 broken valve spring and ran like shit. I would take off the valve cover and check that out!
 
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