My car's compression tested low. Help.

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If I remember them correctly, it had something to do with keeping them from running lean, which they were saying is bad bad (my simpleton paraphrase) and what he was saying, they are set to go real rich under hard acceleration. And yes, they puff a black smoke under hard accelerating. All of them. Believe me, the forum is littered with people posting that same question: "My car puffs out a bunch of black smoke when I punch it, is this normal????". My car was that way from the beginning, which I drove off the lot w/ 6 miles on it.

Oh and I don't doubt you at all. I see you are extremely qualified. But trust me when I say these are not kids who read magazines. They are all professionals who own companies who work on these kinds of car. There are COBB, CP-e, PTP, Race Roots and tons of well known well thought of tuners who are giving the advice. They've torn down lots of these engines and also build them. But I agree with you, everyone should be cautious with who they take advice from.

In the end, everybody agrees, go back to stock and take it to the dealer. Which is exactly what I'm going to do if not this weekend the next. I have to help a friend with his car this weekend and I don't think I'm in any real danger driving mine like this for now.

p.s. I think the term "pig rich" is a bit of hyperbole. As it's almost a running joke now about how rich they run and all the black smoke. lol
 
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I still haven't messed with changing the car back to stock yet. Lots of stuff going on, super busy at work, wife's birthday, mother's day coming up, etc.

Anyhow, I've been thinking of this a lot more. The little bit of smoke I had at idle is now gone. It only came about when I installed an OCC. A friend told me the reason adding the oil catch can made me smoke is because the second PCV lowers the amount of over all flow to the crankcase. But I've since changed that out with a Moroso Check Valve and the little bit of smoke I had at idle is now completely GONE. So is the smell of smoke I smelled in the garage. He said the check ball flows better when used in place of the second PCV, so it allows more flow through the system and therefore cured the issue.

Anyhow, knowing this. And thinking logically, I've come to some ideas on the matter. Granted, I'm no car mechanical guy. But I can think in terms of logic.

1. The car does not use a drop of oil. None. Nada, not even a smidgen. Even over 5k miles, no oil is spent.

2. The car does not smoke (the only reason it did a little is explained above and even that is gone now). But no smoke at all.

3. The car has only 14k miles on it.

5. I've always changed the oil on time or early with high quality synthetics. Currently running Redline in it now.

These are things I know. Now, alternatively, these are things I am thinking, I don't know for sure, but I am reasoning them, maybe some of you mechanics can chip in here...

1. If I had poorly sealed or worn rings. I'd have blow-by. This would cause smoking and it would also cause me to burn oil. Having to top-off occasionally. Is this the case? If so, the logic here is breaking down on the rings theory.

2. My car has "surges" when going WOT. Meaning I can feel the power come in and out quickly during a hard pull. It's almost like it goes between half and full power. Surging back and forth.

3. A friend of mine told me that a slipped or worn timing belt/chain issue would have that effect. True?

4. If so, there is a known issue with my car and it's tensioner becoming loose. There's a thread on the mazdaspeed forums on how to check it and if loose, how to fix it. It is supposedly half-way common. I mentioned this to my friend and he said that could definitely have caused the timing belt (is it a chain?) to slip timing a bit. If that was the case, he said he's had this happen to him on cars and the whole "surging" this is exactly what is experienced with that.

5. Some of you in here mentioned VVT (Variable Valve Timing) could cause low compression. I have no idea what that is or how it ties in, but I see the word Timing and think then that it could be of some relation.

Ok, so again, speaking logically from what I know. It would seem it is not a worn ring issue. Otherwise I would smoke and burn oil. I do not. It is known that timing can cause these surges and I have that issue. It is known that VVT can cause low compression and I have VVT system in my car and low compression.

Any thoughts? Input appreciated. Please don't recommend going to stock and going to the dealer. I am aware of that and plan to do it already, so getting 20 more comments to do so adds nothing to the discussion. Yes it is wise, yes it should be done and yes I am going to do it. I just would like to hear more thoughts about possibilities of my car's current status based on peoples experience and knowledge of cars. Thanks for any responses in this regard!
 
If the timing belt tensioner has known issues then sure it may have jumped a tooth.That would change the compression numbers and the VVT.

Only way to know is check it out You maybe able to see a mark on the sprockets/cogs without dismantling the whole thing,check the workshop manual.
 
If the vvt is computer controlled, it(the computer) senses a rich condition and retards valve timing or spark timing and injector timing to compensate ....resulting in an alternating too rich/too lean condition (back and forth)that you feel or hear as surging/pulsating power output.If your sensor locations changed with the mods this could make the effect more noticable.Your buddies at the tuner shops should be able to smooth this out,you might have to grease some palms to get more tuning time in...even on a chassis dyno.As far as the block is concerned,dont worry,just go back to normal heat range plugs,especially if you don't run N2O,just monitor them.Overall it might only need a pcm recalibration.
 
Originally Posted By: Scott_Tucker
But what is 'too rich'? And what is 'pig rich'? Pig rich seems to indicate that the engine is so rich it is billowing black smoke.


Modern cars are indeed super richly tuned sometimes.I've seen stock 5.7/6.1 Chryslers running high tens STOCK.

If that ain't "pig rich" I don't know what is!

The power surging is commonly caused by ignition timing set too advanced. The PCM hears knock, pulls timing, listens for knock, then runs the timing back up. Then the process repeats.

Get a tuner with more experience on your platform.
 
MazdaSpeed3 cams are chain driven
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Well, just an update.

I don't know if I said this already, but my compression tester from amazon was bad. I borrowed an O'Reilly's compression tester and all cylinders came back above 180 psi. Like 184/183/182/184 or somewhere around that.

So I took the car back to bone stock and took it to the dealer. No codes have ever been given. The car still didn't pull hard at all. But the dealer said nothing is wrong with it since there are no codes being thrown there's nothing we can do and sent me home.

One thing of note. There's another guy having the same issue as me in terms of the “surging” the car is doing. He has the same car but a bit different mods. Here’s that thread if this will help any of you understand the surging issue (he calls it “wavy pulling” but it’s the same thing). He doesn’t mention the dramatic loss of power I have, but maybe that goes without saying (?). Anyhow, read here if interested…

http://www.mazdaspeedforums.org/forum/f11/car-pulls-waves-between-170-220kmph-56229/

But basically, in 5th and 6th gears most especially the car surges through the whole gear. Like it pulls harder then less then harder then less, etc. I’m completely out of ideas now. I don’t even know what to try any more.
 
Originally Posted By: shpankey
I’m completely out of ideas now. I don’t even know what to try any more.


In situations like these, your only choice is to trade-in the car.
 
I don't have time to read all the posts above but did you check to make sure the Cam(s) is/are timed right? Could it be they jumped timing and are leaking out the compression because the valves are opening/closing and the wrong times?

Check to make sure that the gear that the chain or timing belt is driving isn't just lined up with the timing mark but that it's on the right spot on the cam-shaft in-case it sheared the alignment pin. I have seen this fool me before. Timing looks right because the marks are in the right spot but in fact the cam shaft isn't at the right spot connected to the gear because it sheared the pin.
 
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Yes and no... I know on Mitsubishi it does if they are equipped with a Crank & Cam sensor it can tell by 1 tooth off.
crazy2.gif


But I have seen others be off by 3 teeth and the car is really lazy and the CEL doesn't come on because it only has 1 of those 2 sensors or it just doesn't have the check in the ECM to check for it because they assume it will be right.
 
Originally Posted By: shpankey

Well, just an update.

I don't know if I said this already, but my compression tester from amazon was bad. I borrowed an O'Reilly's compression tester and all cylinders came back above 180 psi. Like 184/183/182/184 or somewhere around that.

So I took the car back to bone stock and took it to the dealer. No codes have ever been given. The car still didn't pull hard at all. But the dealer said nothing is wrong with it since there are no codes being thrown there's nothing we can do and sent me home.

One thing of note. There's another guy having the same issue as me in terms of the “surging” the car is doing. He has the same car but a bit different mods. Here’s that thread if this will help any of you understand the surging issue (he calls it “wavy pulling” but it’s the same thing). He doesn’t mention the dramatic loss of power I have, but maybe that goes without saying (?). Anyhow, read here if interested…

http://www.mazdaspeedforums.org/forum/f11/car-pulls-waves-between-170-220kmph-56229/

But basically, in 5th and 6th gears most especially the car surges through the whole gear. Like it pulls harder then less then harder then less, etc. I’m completely out of ideas now. I don’t even know what to try any more.


Behavior like that in a forced induction engine would suggest an issue with your turbo, you're not getting a consistent manifold pressure. Basically something is causing your turbo to drop boost, could be a vacuum leak, faulty MAF sensor, waste gate controller or variable vane controller.
I'm pretty sure the Speed 3 has variable turbine vanes, so you may not have a waste gate, and if they are controlled by a vacuum actuator, I would look at vacuum leaks first. A faulty MAF sensor can also drop boost in certain citations.

Easy way to check if it is MAF, just unplug it and go for a test drive, if there is no change, you know it's the MAF, if that car runs even worse, it's probably something else.
 
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We found the surging issue. It was happening to a fellow member too. It came back to the stock tune not being able to handle the Cobb SRI, TIP & Turbosmart BPV on the stock uncalibrated MAF. Nothing a pro tune won't cure. For now, I put my stock Intake back on.
 
That illustrates the importance of proper software calibration. People who should know better (like the people selling the parts) think you just can throw on performance parts and the computer will 'compensate' properly for them but this is rarely the case and they usually end up making less power. When I worked for Dinan, every single combination of hard parts had their own unique software calibration. Without it they would not work as well as they did.

I still suggest staying away from a short ram intake and get a proper cold air intake, they are truly useless. However they can make power 'on the dyno' if the software is properly calibrated.

I'm glad you finally got it sorted.
 
Welp, I wanted to update everyone. I verified for sure now what the problem was. It was the Cobb Turbo Inlet Pipe as Scott suggested. The thing was, the stock tune could handle the Cobb Short Ram Intake, but when I added the Cobb TIP to the mix, it was just too much for it to deal with. In order to run them both, I would need a tune to calibrate the MAF to those two intake parts.


So anyhow, I went out last night to test drive it after I put the stock TIP on (btw, I had to order one of these since mine had broken) and WOW!. It's very, VERY close to the way it used to be. My litmus test has always been this certain road that every day when coming home from work I would roll along in 2nd and mash the gas. The car would light them up, then shifting into 3rd it would still spin a bit. Then into 4th it would bark the ever loving [censored] out of the tires.

Anyhow, so I go back there to do it. It was a bit unfair too b/c my wife wanted to go with me, which added weight. Anyhow, I stomped on the gas while rolling along in 2nd, and although it didn't flat out go into a full super-burnout, it did spin them pretty darn good, though the car was gaining some traction. This is probably due to 3 reasons... my wife was in the car (185lbs), I now have a CP-e Rear Motor Mount (75 duro) which definitely is supposed to give you traction and the tires are much balder than back then, which kind of acts like slicks on this perfectly smooth pavement road.

Anyhow, I shift into 3rd and it spins the tires a bit (pretty good) and then shifting into 4th it BARK'ed the ever loving [censored] out of the tires again!! All of this is something the car had lost being able to do since I did those upgrades back on Christmas Eve 09. Which is when I put the Cobb TIP on (along with some other mods, that I took off to rule out).

So I just want to report to everyone, after months of speculation, that Scott was right, even though many people said it made no sense (not on this forum, but another that I shall not name). The combination of the Cobb SRI with the Cobb TIP was too much for the stock tune to deal with. It can deal w/ one or the other, but not both. Sure the car will still run fine, as in no CELS or whatever, and will still be a fast car. But I lost about 20 to 25% total power and had the surging issue, where the car would pull really hard for a second, then not so hard, then really hard, then not so hard. Over and over and over.

So what this all means is, all I have to do is get a tune to calibrate the MAF to the Cobb SRI and TIP combo. But for now, I'm just going to leave the stock TIP on it and be happy.

And I want to point out, this phenomena doesn't seem to happen to other manufacturers products on my car. It seems it's only with the Cobb SRI and Cobb TIP combination. I actually wonder if there's people out there that have done this that don't realize they lost power b/c they don't get on it a lot like I do. For me, I noticed right away b/c I had a routine every day and I knew what the car would do. So when it wouldn't spin the tires in 2nd in that same spot and wouldn't even bark them in 4th ([censored], it would barely squeek in 3rd) I knew something went very wrong.

It is so freaking awesome to FINALLY have this figured out and have my car back, pulling like a BEAST like it used to! And now I know that all I need to do is buy the rest of the parts (mods) I want to have on it, put them all on at once and immediately have it professionally custom dyno tuned at COBB in Plano, TX (I choose them only b/c they are really close to where I live).

One thing though, I still can't get the LTFT's to get anywhere near 0. I'm running now these 4....

6.7 (idle)
8.9 (PT)
10.7 (MT)
14.1 (wot)

...so obviously there's even more power to be had here. But at least the car isn't surging and I regained the lost 25% power. Now I'm not scared to race anymore like I had been. The best way I could put it was the car was flat. Just very, very "FLAT". Now it pulls HARD and is a wild child again.

I'm going to check all of my hose clamps tonight and re-tighten them and then spray the surrounding area with carb cleaner looking for leaks.

I think the car will be %100 back when I buy some new stock FoMoCo factory plugs and change out the M1 15w50 thick oil with some 30 weight. I plan on Seafoaming the car, then changing the oil to a 5w30 and then putting in the new factory spec'd FoMoCo Laser Iridium plugs (I have NGK's in now, correct heat range but they don't idle smooth for some reason). I really believe that's the last little bit I'm missing to be %100 back to where I was before. I'd say I'm at about 95% right now. Very, VERY close.

SO FREAKING HAPPY!!!!!!!!!
 
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