I’ve searched through a few other threads re: zero compression, and the outlook always appears grave. I’m hoping my situation might be different.

I have a 2002 Mini Cooper S (R53), about 116k miles, with the following relevant mods:

Alta Cold Air Intake
MSD Ignition Coil Pack
Craven 15% Supercharger Pulley
Craven 2% overdrive lightweight crank pulley
Newly installed 2006 Supercharger which was “new to me,” but had 20K miles on it
D1-Spec Throttle Controller

Driving down an access highway that services the interstate yesterday morning, I opened the mini up from 60mph to about 80+mph. It pulled well until it got to the 80+, then I felt the car stumble and it started to sputter. I let of the gas and it continued to sputter and slow down. I pulled down an off ramp and onto the shoulder. The car was sputtering and shaking so I shut it off and tried to restart it. No go.

I tried to restart the car for about 20 minutes. Finally I got it to start back up again. The car picked up where it left off, sputtering and shaking. I was about 5 miles from the dealership on back roads. So I set out to see if I could make it. I could only manage about 10mph. When I pressed on the gas pedal, there really was very little response. It was as if it was not getting enough fuel. The car just kept slowing down further and further until about .7 miles from the dealership it finally stopped. The car would restart, but every time you put a load on it (let the clutch out) it would just about stall. I checked and the car threw two codes: P0300 code, “Random/Multiple Cylinder Misfire Detected”; P1689 code, “Electronic Throttle Control Monitor Level 2/3 Torque Calculation Error”.

Some background ... about a week ago, the same kind of thing happened in almost the same place. However, while I was limping my way to the dealership the car suddenly got better. At that time the car threw a P0303 code, “cylinder #3 misfire”. I chalked it up to a clogged injector that righted itself. I ran a can of seafoam through the car and it seemed to clean it right up. The mini was running fantastic after that.

Got a call from the dealership yesterday. They said that cylinders #2 and #3 have zero compression. Cylinders #1 and #4 have about 150 compression, which they say is low. They added some oil to the cylinders when they did the test (in case some flooded and cleaned them) but that didn’t help at all. They took off the valve cover and they say everything looks fine and seems to be in one piece. They put a scope in the cylinders and said it also looks good too.

They suggested I might want to do a smoke test to try and determine where it’s leaking. Good idea?

Any ideas or other recommendations? Any idea what could be the problem?

Thank you in advance.

 

If compression is zero between 2 & 3 I would say you need a head gasket.

Do a leak down test to confirm, but it sounds like you're in for a head gasket.

I would recommend having the head gone through and valve guides & seals replaced at the same time.

150 is not low for a force inducted engine, that is about median between good & bad, had it been a base Cooper then I would agree that it is low.

 

I'll be the first to admit, I am not familiar with all these Jedi compression tests. I thought he said they did a leak down test, but I'm not sure now. Will a leak down test confirm a head gasket failure between 2 & 3? Will the colored smoke test help more definitively help diagnose (or eliminate) anything?

The conversation basically went ... "yeah, its going to cost a lot, basically like $10k+, so our recommendation is that you might as well park and junk it."

 

Compression tests only tell you so much, to properly diagnose a low compression/leak down situation a leak down test is required.

Smoke tests are useless on something like a headgasket failure, a leak down test will more accurately diagnose the leak.

If there is zero compression between the two cylinders you will hear an air leak from the either cylinder as soon as compressed air is applied to either cylinder 2 or 3.

If their recommendation is to park it or junk it because it's going to be $10,000 to fix I would recommend taking it elsewhere. They obviously don't have the knowledge to properly diagnose your engine failure.

A simple head gasket job with minimal head work will cost you around $2-2500 depending on where you go (besides the dealer, that'll be a $6,000 visit).

 

I have a "go to shop" for all my heavy lifting, so they would get the nod for any work like that which you speak. The only rub is, I have to trailer the car up there since its over a hundred miles away.

Wondering, while its at the dealership for diagnostics, whether there was any other direction I/they should be looking towards in order to help narrow the trouble and not duplicate the costs.

While I might get a little choked up on +/-$2k, it is certainly is way more easy to swallow than $10k ... for that price it best be ready to race competitively in SCCA.

 

Did my head gasket this last summer for $200 using only oem parts. Sounds like your head will need to come apart, but the huge price for a gasket always gets me. I understand, many expenses to be paid other than just fixing the car.

Good luck, definitely worth towing it to your trusted mechanic for a job this important

 

By chance, did you have a similar situation/symptoms with no compression in one or more cylinders?

 

Sorry no, I just had water in the oil.

 

I fix "troubled" cars like this myslef, so don't think I am suggesting you shouldn't fix it.

But after talking to several people who had excessive estimates from dealers, then went ahead with engine repair work despite the cost, only to find it didn't work out - most dealers don't do internal engine repairs! That half-arsed $10K estimate is a warning they don't want the work. Listen to the warning!

Take your car to an indy or a performance shop that routinely opens engines up. A cylinder head gasket with some minor head work is not a big job on a MINI.

 

Update:

Was finally able to put the mini on the trailer and make the 100+ mile trek to the shop this past weekend. They opened her up first thing Monday morning and determined the "no compression" culprit to be the exhaust valves in both cylinders #2 and #3. It still remains a mystery how both 2 & 3 went at virtually the same time.

So they're sending the top out to a good machine shop for some head work. As for the cost, nkfry nailed the range for the gasket & head work. Way more reasonable than the dealership's park it or, junk it because it's going to be $10k to fix it.

But with the head already off, why stop there, right? When, for a few hundred more, a good port and polish is within reach. So, in addition to getting a working car back, I'll have something else to look forward to.

David ... not sure the dealership didn't want the work. When I picked the car at the dealership, the shop manager (not the store front rep, but the guy in the shop) started to cop an attitude and get all pissy with me. I took a few deep breath ... and let it go.

 

Glad you've got a workable plan. My point was a little more subtle (not that it really matters). What I was trying to convey is the dealer should know these two things 1) any skilled shop could pull the head and send it out for machining and re-install with a new head gasket. 2) you are unlikely to agree to a $10,000 whole engine replacement. So, by offering only #2, they are giving a signal that they don't want the internal engine type of repair work. I am sure they would be happy with the high profit engine switch out or if you walk away from the car and they fix it or sell it at auction.

 

Weird it was valves, the S heads use sodium filled valves to prevent burned valves. The Coopers had more issues with burning exhaust valves as they weren't sodium filled.

With both pulleys on your car are you running colder plugs? That could be the cause of this whole dilemma.

NGK Spark Plugs for cars with reduction pulleys.

 

Nope ... that was on the "to do" short list. It would just suck if that was the case. Better mention this to the shop.

 

Chances are that if you have burnt exhaust valves that running the wrong plugs for your setup is what caused the damage.

We have customers that run their stock heads HARD and never have problems with burnt valves when the proper plugs are installed.

Sorry about your luck, let us know how we can help.

Detroit Tuned
586-792-6464

 

S heads have inconel exhaust valves but they aren't sodium filled. Even the base engine has premium material, using 23-8N.

Burned exhaust valves on an unmodified S should be virtually non-existent. The problem comes when you start with mod's that the engine wasn't originally calibrated for, like the reduction pulleys. I'm sure when Rover group did the calibration these open loop over boost and inlet air over temps were simply extrapolated out, so it's a crapshoot.

Even worse if you put a 17% pulley on without porting the exhaust or without running a header since it's going to crank up the EGT's even more, especially on warm days. Plugs have almost nothing to do with burning valves, unless you're getting into pre-ignition. Hot plugs worst case will blowtorch a big hole right through the piston top due to pre-ignition (not detonation), but won't impact EGT's as long as there's no pre-ignition.

BTW, spark plug heat range is only half of the story on replacing plugs. I've seen about 4 or 5 different recommendations in these forums. You are always going to be better off using the OE specified plug for your vehicle and going a heat range colder than in substituting another plug type/style. This is because the tip length of the electrode is a very critical element in its performance for both cold fouling and pre-ignition. The Tritec engine was specified with extended tip plugs because it gives the best of both worlds. At lower rpm's it runs hotter, preventing fouling, and at higher speeds and loads runs cooler (than standard tip plugs) due to the charge cooling effect. The original work I did with Champion determined that RC9MCC plugs (medium projected tip) were best overall for the base engine (not S/C), but Rover wanted long life plugs so they spec'd the NGK's. And Champion vs. NGK heat range conventions are opposite. With Champion, the lower the number the colder the plug.

 

Well, since this thread has grown some legs, I figured another update was in order.

I picked the car up this past Friday. My garage sent the head out to another shop that does all their head work. That shop:

(1) replaced all the exhaust valves (see pics below);
(2) said the intake valves were fine, so they left those alone;
(3) said the cam was damaged (see pics below), and replaced it with a used low-mileage oem cam they had on the shelf;
(4) ported and polished the head.

My garage was really happy with how the car turned out, saying it really rips now. One of the guys at the garage had the same port and polish job done done to his R53, but their seat-of-the-pants dyno indicate mine is a little stronger. Customer hype? Maybe, but I can tell the performance of car is exponentially better than anytime during which I've owned it. However, given my luck lately, I've been apprehensive to get on it and really opened the car up. I just don't want to break her again. I've gotten on it maybe 1/2 to 3/4 throttle, and I can tell it has some scary go-go juice.

Notwithstanding wear & tear, I'd really like to make this build as bullet proof as possible and try to avoid this type (or any type) of damage in the future. Upon my request, my garage already installed one step cooler plugs (thank you nkfry). I'd welcome, as I'm sure anybody else who stumbles upon this thread would too, any other suggestions on how to accomplish that at this point.

Lump mentioned porting the exhaust (that's done now) or running a header (considering this as a future mod). If I need to run a header now to prevent this from happening again, then I'll get one now. To that end, any recommendations on headers would also be welcome (I live in a state where check engine lights are verboden on a vehicle during inspection, so any header set-up would need to either: (1) not throw a code; or (2) be resolved through the use of other means).

Lump also mentioned pre-detonation. I roadrace motorcycles semi-professionally and lost the motor in one of my race bikes a couple of years back when a lower grade octane fuel was used (93 instead of 108) in my built SuperSport (higher compression) motor due to pre-detonation. The damage to the racebike was similar to the pics below, but also damaged the cylinders. I've always used the OEM recommended grade of octane in the car or better, but how sensitive are the R53 to octane? I'm wondering with the cumulative 17% on the pulleys, whether the car might require the highest grade octane available at the pump (to avoid pre-detonation, assuming this was my issue).

Anyway, here are the pics:

 

Wow, that damage looks severe enough that I think it was more than low-octane fuel that caused it. You didn't mention a tune in your original post. Was there a tune on the car?

 

Nope, no tune. I've owned it for only a year; the two prior owners, both women, thought the car was "cute" enough and left it untouched.

 

Looks like you've been running astronomical exhaust gas temperatures! And that cam spalling is very unusual. Almost looks like you've been running very high RPM's and getting into valve float. Stock valvetrain if I recall correctly gets into valve float at around 7300-7500 rpm.

That's really the problem I mentioned. Effectively you're running a 17% higher supercharger speed so your getting into the outer limits of what the production engine calibration was designed to run at. And even at that, I'm pretty sure that the calibration engineer at Rover was just extrapolating out the fuel and spark map for the kind of boost you're likely to be running, since his calibration engines would not be capable of producing those boost levels. When you start to "uncork" the exhaust side with a port job, header, or a combination of the two, the boost level and IAT will drop as well as the EGT's which then is overall thermally safer. Still, you're likely to be running EGT's so high that you risk melting the Cats (very likely so on the pre-cat), which then only further raises the backpressure and EGT's. So based in this damage, there's a decent chance that your pre-cat is partially melted and plugged (will only be able to be seen with a borescope from the cylinder head side) and I'd suggest having it scoped. AFA the tune, I would expect that you should have a tune done and it should be running at least 11.5:1 AFR @ 5000 rpm WOT, rising to at least 10.5:1 @ 6800 WOT under "standard temp and pressure" conditions (sea level @ 72F ambient) and not leaner than that if you don't want this problem coming back.

A word about Pre-ignition:
It is not detonation. Pre-ignition is when a hot spot in the chamber (usually the spark plug electrode) gets so hot that it initiates the start of combustion prior to the spark timing. Effectively, pre-ignition is like running way over-advanced spark timing. This is extremely destructive and can get out of control in just a couple of seconds to the point of blowing a hole right through the center of the piston crown. That is the most common failure mode of pre-ignition although valve burning is also possible. The piston crown will literally look like someone took a blow torch right to the center of it.

Detonation is when the as yet to be burnt "end gases" in the combustion chamber auto ignite due to the expanding flame front of normal combustion heating those gases up before the flame front arrives. So instead of a controlled burn, it's like a small explosion at the edges of the chamber. This is the typical "pinging noise" you'll hear on a full throttle acceleration. Severe detonation usually manifests an erosion of the edges of the headland of the piston or a cracked headland. The detonation in a Tritec engine (as with many 4V/cyl engines) occurs first in the sides of the chamber, not under the exhaust valves as most would expect. This is one reason why the Tritec engine has a bit of chamber fill (almost looks like a convex ridge) in the sides that runs through the bridge between the intake and exhaust valves. I see that some modders grind that area out, which I think is not advisable if you're not running racing gasoline.

Severe detonation can raise chamber temperatures high enough that then it triggers pre-ignition. This in fact, is how pre-ignition testing for spark plug selection is conducted. Spark is overadvanced (around 8-10 deg.) for a few seconds to then trigger pre-ignition. Needless to say the "pucker factor" gets pretty high when running those tests on a very expensive prototype engine!

Best wishes in getting it all sorted out with the shop.

 

Weird ... I've seldom let the rpm's ever go over 5500 and pretty much never let them touch anything over 6000.

That's pretty much as far as I got ... I have to study the rest of your post. But I understand enough to know this doesn't bode well for me: "you're likely to be running EGT's so high that you risk melting the Cats (very likely so on the pre-cat), which then only further raises the backpressure and EGT's. So based in this damage, there's a decent chance that your pre-cat is partially melted and plugged."

 

Hey Gecko, I just read this entire thread and had another thought for you to "protect" your now repaired R53. Wow, man......I respect the HECK out of what you did in pulling the car from the StealerShip and towing it over to an indie shop. GOOD FOR YOU. Plus, now you've got a bass-*** newly repaired MINI that's even faster than before!

Due to the fact that you were NOT running one-step--colder plugs.......I also have a 17% reduction pulley (Alta) and read about that requirement, right at the outset of putting my 17% on my R53.....the ****other*** thing I remember reading was that the MSD Ignition Coil Packs = CAN = cause "sparks that are TOO strong" that might cause damage.

I actually read SEVERAL posts on this forum from Way, where he does NOT = EVER = use the MSD's (he only uses the OEM coil packs) due to this issue.

Maybe your whole problem/breakdown was due to not having the one-step-colder plugs PLUS running the MSD, in addition????

You might just pull that thing OFF your R53, reinstall an OEM coil pack and CALL IT FIXED FOR GOOD bro, right?!!!!!

 

Oy, my condolences . . . sounds like you ran out of NyQuil and had trouble falling asleep. Hope this thread helped.


Well, I appreciate that . . . but my wallet and two-wheeled racing program (https://www.northamericanmotoring.co...ml#post4139424) were not at all happy about it.


Yup, I had read similar posts too. I appreciate you bringing this up. At the time I read them, to me, they sounded a bit speculative and inconclusive though. I was waiting to see what my shop said and what responses I got from this thread. While my garage didn’t mention this as a possible suspect, removing it as a prophylactic measure is still under consideration. I definitely want to avoid this type of damage in the future.

While the extra go-go juice this build has bestowed (though I still have only opened it up maybe 1/2 to 3/4 throttle) is great . . . it has highlighted the fact that my clutch is slipping (noticeable in 3rd, 4th & 5th gear) and I’m currently on borrowed time.

 

Those pics make me sick.

 

Tell me about it....

And for my next trick, I'll need a volunteer mini from the audience....

 

No volunteer MINI

Glad you are in good spirits about it, I think I would go from sick to rage on what happened.