When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I did a search nothing came up with nil compression. My 2006 E55 with 81k miles and ONLY an 83mm fixed pulley and tune was running perfectly and I had not given it the mumbo for a few days. I had just pulled onto my long driveway when it started running rough. The next morning the start-up from cold resulted in an instant cloud of oil smoke which went away when I drove it slowly to the Merc dealer. Other than running roughly the smoke quickly went away on that drive. The dealer found nil compression in #2 and says I need a new motor and they don't want to carry out the repairs. As there were no untoward noises when running, the compression loss and smoke could only be the ring(s) failing. Any ideas before I attempt a head pull. Can the engine be lifted off the mounts enough to access the rod bolts so I can push the piston out the top to see the damage? Thanks in advance. Cheers.
It can also be head gasket or bent valve. A leak down test will give you more information. You don't often get 0 compression all of a sudden with just rings. Pop some oil in the combustion chamber and try again. I would definitely repair if possible. No way to know what you are getting with a second hand engine. Find a better shop.
If the engine needs work even to pull a head....just pull the engine. They are real easy to remove and work on and in the end will save you a lot of time and labor with it right there on an engine stand.
I vote head/valve issue also with tw2 ,,, get a cheap borescope that plugs into a phone/laptop and look around through the spark plug holes ,,, zero comp usually comes with a lot of oil, loud noise and a big hole
Thanks all for that, I couldn't see how oil could accumulate in a cylinder due to broken rings. Does anyone know how many hours a good shop might charge just for the engine r&r ? Cheers.
I am almost ready to pull the head. With the valve cover removed, I see one intake valve on the nil compression cylinder has oil pooled above the valve in the port. This would account for the smoke on start-up. I must have had the valve closed when starting the work. I don't see how a blown head gasket could be involved. Would those who know agree that it can only be a failed valve stem seal or excessively worn valve guide? Thanks for your assistance.
So folks, I would like to share this with you. I got the head off enough to see inside. You can clearly see the pre-ignition that has been occurring to erode the edge of the piston and then the chuck of liner taken out. The motor is junk. All it had on it for mods was an 83mm pulley and a TUNE. I won't say whose tune quite yet as I have yet to contact them. Is this motor rebuild-able yes, is it financially worthwhile? Please give me your opinions. Cheers.
Thanks but that wouldn't that cost more than the car is worth?
Depends what it is worth to you. I just mean strip it and replace rings, HG and all seals. No point putting another engine in and having a new problem. I have spent 10k+ on my 4k mr2 and it's about to get a whole lot more.
Thanks tw2. I have had some advise from a very good race car mechanic who has seen the exact same damage from a weak or broken ring allowing oil to hot spot. A weak injector can run that cylinder lean but I would think the ECU would pick it up. The bore liners look like chrome plated aluminum ones. I blew up the pic, looks gruesome.
Thanks but that wouldn't that cost more than the car is worth?
Almost anything you do to it is going to cost more than the car is worth. Unless you can find a used engine and install it yourself while hoping it’s good, you’d be better off selling the car as is and moving on money wise.
Another forum member who had a CLS 55 just went through this. He was going to sell the CLS but decided to fix it. If your car is in good shape and you like it, might be worth finding a used block as TW2 said and swap it out. Indy shop might do it for a reasonable price if you aren't up to it.
Hate to even go down this road but reguardless if the tune was bad...it is up to the buyer/owner to make sure it is right. You can not take it for granted that it is correct. Every tune, and I mean EVERY tune I have bought and we are talking at least 10 to date, they where never correct on the first down load. I always needed at least two more after the original to get the AFR where it needed to be. I even had a tune where the tuner made the mistake of sending a tune for 550cc injectors when mine where stock. Ran dangerously lean and I saw it on the wide band. I would have popped my engine long ago if I did not tune it by eye through the wide band.
Also I can't see your engine living for two years with a bad tune as it should have popped a long time ago but who knows.
Hate to even go down this road but reguardless if the tune was bad...it is up to the buyer/owner to make sure it is right. You can not take it for granted that it is correct. Every tune, and I mean EVERY tune I have bought and we are talking at least 10 to date, they where never correct on the first down load. I always needed at least two more after the original to get the AFR where it needed to be. I even had a tune where the tuner made the mistake of sending a tune for 550cc injectors when mine where stock. Ran dangerously lean and I saw it on the wide band. I would have popped my engine long ago if I did not tune it by eye through the wide band.
Also I can't see your engine living for two years with a bad tune as it should have popped a long time ago but who knows.
i previously had pricey off the shelf tune and asked the tuner what gives...when taking off aggressively from a dead stop the engine will bog hard.
tuner states...i need to have my injectors and fuel pump check and/or replaced. it is a mechanical issue and not the tunes fault.
well...it was the tune. the trims were always wayyyyy off. i even stated this when emailing, their response to that was, the trims don't really mean anything on these engines. my trims now with my own tuning with HPTuners...0 to +/- 1 percent, both long term and short term trims. throttle response from all rpm ranges is amazing, and there were NO issues with my injectors or fuel pump. I have a M156 but i'm just trying to paint a picture here of the "tuners" out there.
BTW are there two of these same threads? can we merge them as i recall you posted photos of your spark plugs as well.
05-01-2020, 03:53 AM
