Car Vibrations, Exhaust Smell Problem.
 

I did a loose search for the issue I'm having. But an exact match to my problem isn't in the system quite yet. (From what I've scanned at least.)

Sorry for the title of the thread. I'm not really sure what to call it.

First and foremost, I am mechanically enclined, but I'm not great at it. I'm a computer technicain, not a mechanic. The bulk of my experience is having a mechanic tell me what is wrong, how to fix it, and then I go and do it. I have practically no troubleshooting ability on my own.

I bought the car a month ago. It had a bad fuel-like smell and idle troubles where the engine would cut out if you left it at idle for more than 5 seconds. I only drove it 7 miles since then and then stuffed it in my garage. Two weeks ago I started it up to assess it's behavior. I tried it again today to see how it might differ. Nothing has changed between the three times I've started the car.

1: Car vibrates like all hell. Not so much when you give her some gas. But when you let her idle, it's like an earthquake in the cabin. Eventually leading to the engine cutting out.

2: Really, REALLY bad fuel/exhaust smell coming from the exhaust. Nowhere else though.

3: When I started it up, this black liquid shot out of the exhaust (and continued to shoot out for about 4 or 5 seconds) and splattered against the wall. It has no substance. It's like water mixed with carbon. I'm slating that as condensation that built up in the exhaust that was kicking it's way out.

4: Some smoke came out this time. Not a whole lot. Just a faint trace. Mildy burned the eye's, but I was in the back half of the garage when I did it - right next to the exhaust. It stopped kicking out smoke about 30 seconds into the 'run.'

5: No fuel or exhaust smell coming from the engine cavity. No smell could be detected from within the car either during operation.

I called my father who is more mechanical than I, and he said she might just need a tune up. But these cars can be such a fickled thing.

Before I go and seek outside diagnosis, I figured I'd ask the guys that have way, way more knowledge on these cars than I do. Before I end up breaking something or hurting myself.

The car is as stock as stock can get aside the addition of an Autometer boost gauge that doesn't work worth a crap. I got a GReddy boost gauge that I'm going to be replacing it with once the corresponding temp gauge gets to my door.

Just want an expert opinion. It's like some of the spark plugs aren't working or something.

Side note: The previous owner treated the car like crap for 5 years of his ownership. No tune ups, no nothing. He can't even remember the last time he changed the oil (which I already did) flushed the radiator (which I also did) he didn't even remember the last time he washed the car. Or wiped down the interior.


I'm not driving the car as it's not my DD. But I'd like to get it to the point where I could drive it with confidence when that rare good day comes around.

Much appreciated,
T

that is a car i would not have bought...

almost sounds like you have a blown motor. start with a compression test.

+1 on compression check

when i put my test pipe on and drove around for a bit...then i'd come to a stop light and errthang would just rattle like a mother bitch! then i found out the pipe was rubbing against the brace that sits right below it. went to a muffler shop and had them move the hangers around for like 5 bucks and no more rattling. the exhaust stills smells worse than the inside of an ass tho. cant do much with that unless you put a cat back on.

Sound to me like a blown motor. I just recently started having those kind of problems or symptoms after pushing my car. Bad idle (vacuum was at 10-12) and really bad exhaust smell. I'm goin to get a compression test this Wed. but I think I blew it.

i have kind of the same prob.......nut i doubt is a blown engine...cuz the cars still fast as hell...just idles like a bitch though.

damnit, im having similar symptoms....except my car doesnt die. it mosly happens when i start it up (plus its cold here) but it also shakes a bit after its warmed up and i drive around. usually it stays nice around 700-750 but sometimes i can see the rpm's flickering a bit.

my car also shoots out from the exhaust. and im not having any driving issues and i dont drive it hard. i might step on it once in a while but usually not very often or for long distances. just enough to remind me of the power.:) i just recently installed a bov and i seem to notice these things a little more. im gonna try adjusting the bov and see if that helps any.

what other symptoms would come with a blown engine? I mean, is the blown engine pretty obvious?

OK, before everyone gets all excited with the blown motor posts -

I'd first make sure the vacuum line to the MAP sensor hasn't come off. That would produce exactly the symptoms you're seeing. Pop the hood, back driver's side of the engine compartment right above the oil filter is a black box bolted to the firewall with an electrical plug going to it. It should have a vacuum line running to it with a black plastic filter in-line. REAL easy for that to get knocked loose.

If that's not it, I can help you out. I'm not too far from PCity and can do a house call :). I'll PM ya here in a sec.

Dale

wut about if it was running way to rich. Could be throwin unburnt fuel out the exhaust,and it would definatly have a hard idle. i unno

yeah, my car drives pretty good on the freeway. My primary is still hitting 10 psi but I don't want to go over 4500rpm to see how my secondary turbo is pushing. Don't want to damage more shit. also I did check if the map sensor vacuum line is connected and my pfc also is getting a reading on it

if its as stock as it can get, meaning no upgraded ecu or anything how could it be running rich.

Take dales offer to make him see the car, he knows what hes doing........ i think... lol jk hes a good guy

sounds like just a tune to me.

The 13B virbrates a bit when warming up anyway. The black liquid it spits out of the exhaust is condensation due to long periods of lack of driving and the cold weather. The exhausts always smell bad, as long as it doesnt smell like coolant and blow clouds of smoke after the car has warmed up, then its unlikely to be a broken coolant seal.

The idle sounds like it needs to be lowered a bit, but the engine will idle higher than 1000 until it warms up, in which it should drop to around 750rpm. It could also be a number of minor things. I would give it a good service and oil change, making sure to change all filters and spark plugs. Also change the fuel if you suspect its not been driven in a while.

I wouldnt jump to conclusions, as there really isnt anything you have said that sounds like you have a blown engine.

i have a issue with my car.. i could smell like coolant rubber hoses... because i had a problem with my coolant hose connected to my turbo... changed it and sudden i could smell the coolant + the rubber hose from the inside of my car... any clues?

Checked the MAP Sensor and it's connected properly. Assuming what I was looking at was the right part.

Bolted to the firewall right above the oil filter. Little black box that says "Mazda Boost Sensor" and has a vacuum line and an electrical plug on it.

The car's idle problems happen at all temperatures. It happens when you first start it, it happens when you've run it for an hour (as I've been told by the previous owner.) It happens if it's 32 degrees outside or 92 degrees. The behavior is 100% consistent each time.

talk to Dale

Compression Test Confirms It!!
 

I did a compression test and the front compression chambers are low. This is what I got.

Rotor #1
1= 8.0kg/cm2 Rpm 259
2= 4.8kg/cm2
3= 3.8kg/cm2

Rotor #2
1= 8.4kg/cm2 Rpm 261
2= 8.7kg/cm2
3= 8.5kg/cm2

I plan on doing a compression test late Friday or early Saturday. I just don't want to deal with trying to get down to the spark plugs right now.

That's one thing I miss about my Impreza. Really easy to get to the plugs.

this is what my rpms are doing when idling. you can see my rpms moving up and down a little bit. it is more noticeable at other times and you can feel and hear when it drops a little. (the noises you hear in the back ground are the seatbelt light and the steering pod mount is loose because i wanted to try to get a closer video....i used my phone he he)

i revved it a little to see how the rpms drop pretty low.

like i said, my rpms didnt move as much as they occasionally do but i dont know if this is normal. i also dont think the rpms should be dropping THAT low when i let go of the gas.

just trying to get some info on what might be the problem if there is one. thanks.

http://www.youtube.com/watch?v=Agkj1GpPYuY

Did a compression test with a Piston engine tester. However, I have no clue what data to really record off of it.

I tested each rotor three times just for the heck of it. The front rotor seemed fine when I opened up the testers valve. I got 3 steady pulses, each registering the same volume of air moved.

When I kept the valve shut and cranked it, it immediately jumped to 130 pounds per square inch (give or take a few pounds) and stayed there.

The rear rotor registered in at 125 (or so) pounds per square inch. It also got 3 stead pulses of equal pressure when I opened the valve and cranked it.

Both rotors, while the valve was open, registered about 125-130 p.psi.

I hooked up my GreDDy boost guage and the entire time the car was idle, it was registering between 15 and 18 hg

I didn't actually drive it. Just left it running for 20 minutes.

I did notice something though. Once the car warms up, it's pretty ok for the most part. It idles just fine until you put it in gear which boggles the heck out of me.

If you depress the clutch, the idle is fine. If you put it into any gear (while the clutch is still in) the engine will start dying. It will stay alive, but the RPM's will drop.

The horrible vibrations go away once the car warms up, unless you put the car in gear. I didn't put it in gear and then start driving it though. That's a test for tomorrow I suppose.

I'm changing the spark plugs while I'm down there. From the information I've gathered, they're remarkably old and have tens of thousands of miles on them. Changing the wires while I'm at it.

well you want the valve out... or depressed. You want to register the bounces. Front and rear rotor. Here's a link on a HOW to. Also make sure the car is warmed up before doing the comp test. a cold comp test is useless.

http://www.fd3s.net/compression_test.html


the pulses can be steady but what psi are they exactly? you want to be above the 80-85+ range on each bounce.

I followed the instructions you listed when I did my test.

I registered the bounces. There was no delay or break in the bounces. Steady bouncing over a prolonged period of time. Each one registered at about 80-85 as you stated. This was on both rotors.

When I closed the valve, it registered a solid 120-130 when I cranked the car for 5 seconds.


I changed the spark plugs out. Didn't do a whole lot of anything that I can identify. My boost gauge doesn't bounce between 15 and 18 inHg. Now it just sits at 19inHg and only budges when I start giving her gas.

so the strong odor of fuel coming from my exhaust is normal? i was worried that maybe my car had a fuel leak somewhere, but it drives perfectly fine. i too have slight vibrations at idle and warm up, but nothing cabin-shaking like you described.

Actually, since I changed the spark plugs, the overpowering smell is pretty much gone. All I smell now is your standard exaust fumes coming out the rear. Maybe a bit worse than what one would expect, but I don't know what the car was like in good condition so I can't exactly compare.

It's not really cabin shaking persay. It's a low idle that makes the car shake. That kind of thing.

Going to try to explain this again for the sake of myself so I make sure I got everything I can think of explained:

Car starts fine each time. No problems or hesitation whatsoever. No matter what temperature the car is, or how far/long/hard it's driven, it will still happen.

Car idles just fine so long as I'm not doing anything. Depressing the brakes doesn't do anything to the idle. Depressing the clutch does nothing to the idle. Gas obviously does what it is that throttle bodies do. If I give her gas, she'll return to idle. She might dip a bit low on the way back down, but then spring right back to the 750-1k mark.

Now, if I put the car in gear, the engine goes absolutely apeshit. So far I've only tested what happens if I have the clutch disengaged and I put it in gear. I haven't exactly completed the 'put it in gear' process here. I plan on doing that tomorrow because tonight I got to re-install the steering wheel, gauge cluster, drivers seat, etc.

Now, occasionally she'll idle rough for no apparent reason. But it happens like clockwork, every time when I put it in gear. It doesn't matter what gear. Also, when I put the car in gear, the boost gauge drops from around19hg to 15hg and starts slapping back and fourth between the two numbers.

Tafumi,
My car had the EXACT same symtoms as yours just two months ago. Bad smell, rough idle, etc. After performing a compression check my rear rotor showed 90 psi max and only one "good" bump on the compression gauge(blown apex seal). However, it was pulling 20 inches of vacuum which is good. I guess I'm telling you this because a compression test is the best measure of health you can get while the engine is still in the car. I would not jump to the conclusion that your engine is blown because you do have some healthy compression numbers....even bumps and a good number on the strongest face (because you're using a piston compression tester). Get ready to become very familiar with wiring, sensors, etc. as you are going to really have to search for the problem....but the guys on this site are great and willing to help. I don't think your engine is blown but something is causing these symtoms. Good luck and check what the people here suggest.

From the description of your compression test, that sounds like you have a good motor. I think you're in the clear there.

Idle going goofy when shifting into gear is most likely the clutch switch. Do some searching on that. It either needs to be fixed or replaced. If it's bad, the ECU goes pretty bonkers.

Again, let me know if you need some local help.

Dale

i'm just gonna throw it out there.... tps? Sounds like engine is good to rock.

Thanks for the information Dale.

I took out the clutch switch. I'm assuming this is it:

http://i216.photobucket.com/albums/c...i/S5300236.jpg

The little white button was barely peeking out from the screw housing. When I removed it, the button completely receeded into the screw and won't come out. So if it wasn't broken before, I broke it. Assuming that the above is the clutch switch. It was the only thing there.

EDIT: I just took the switch apart. The spring inside of there was broken into 4 different smaller sections all kind of tangled up with one another. I'm not entirely sure if that's normal or not, but that's what I'm working with here. Now I need to figure out the part number so I can order a new one from Mazda on Monday.

Or just find a new spring. Which is probably cheaper. Suppose tomorrow I'll be doing a Home Depot run or something.

Well, the clutch switch seems to have done the trick. The car still is a little rough when starting, but now the shifting is smooth. I replaced the spring with a spring from a ball-point pen. It works, but I don't consider it a true fix action. I'll probably call up Malloy tomorrow and order a new one just to play it safe.

Still a stupid amount of exhaust fumes. Just doesn't seem natural. I'll have to give her a prolonged run and actually drive around a bit to see what else is screwing up. I got an oil leak somewhere that devloped about a week ago but it's a tiny leak. Over the span of a week, only 3 or 4 ounces of oil (guestimation) has leaked out. But it's those tiny leaks that get you. I don't see black smoke anywhere (don't even see it boiling off the engine or other hot parts during operation.) It's coming out from somewhere under the UIM on the drivers side. It's running down the spark plugs of the front rotor but it's not coming from the spark plug holes. Somewhere above that I can't quite see because of said UIM and associated elbow is in the way. I don't look forward to taking it off and subsequently pincing all kinds of vacuum hoses when I put it back on.

Back to tinkering with me. She is still a little finicky on the idle so obviously I haven't completely eleviated the problem.

if there are exhaust fumes in the cabin then it's due to an exhaust leak. is it a stock exhaust? what cat/exhaust/dp do you have on it?

does it blow smoke after the car has warmed up? NO, if so then its just condensation.

chuck up a vid!

The exhaust is stock as far as I can tell from referencing pictures on the net in comparison to what I see on the car.

The previous owner did no work to the car, but the owner before that had it sent to Rotary Performance in Garland TX for engine work. The engine was rebuilt from what I have on paper. But there are other things I can see that were done to the car. The AST is missing and some of the vacuum lines are plugged with bolts and whatnot. A boost gauge was installed, though it doesn't work worth a damn so I replaced it with a GReddy gauge.


The car only blows smoke for the first 30 seconds or so. It's white, and as I said in another post, I figured it was just condensation burning off.

I have her sitting in the garage and I open up both the garage door and another door to help ventilate the room when I start it. Within a minute, my eyes start burning (provided that I have the door open.) The fumes aren't coming from inside (or leaking into) the cabin. Again, that is so long as I have the doors closed and the windows up.

I did a brief look-over of the exhaust when I had the car jacked up a few weeks ago and it's rusted pretty badly. I think my next stop is to take a look around. It's not as bad as it was before I replaced the spark plugs, but it's still pretty rough. Even if I bring it outside of the garage, into the open, it still burns my eyes. But there is no visible smoke or anything once the condensation burns off.

my car has the same problem/symptoms ,and i am saving up money to fix it.

rough idle, exhaust smells like crap, and my gas mileage was like, single digit.

turns out to be a blown LIM gasket.

if the car has had performance mods, i highly doubt it would have a stock exhaust

wait are you saying that it burns your eyes outside the car? then that's normal. rotaries stink. seriously. we kill brain cells with our exhausts.

It's only outside of the car, and it's coming from that exhaust. Maybe it is normal but I'm not used to that level of exhaust.

Glad Florida doesn't have emissions testing I suppose.

You don't just kill brain cells with that stuff, you can kill small woodland creatures on contact with our exhaust.

I'm still going to take a look at the exhaust system. Eventually replacing all the sections because I like it when things are nice and neat and new.

I had that same exhaust/rich smell condition on my FD when I bought it in Sep07. My uncle who is a mechanic said that there was a leak in the UIM & LIM. I changed out both gaskets and now the smell is very faint to almost none at all. It doesn't make my eyes water and it's not embarassing to take girls out on dates in my car anymore lol!!!
give it a shot...just my 2 cents...

If there was a leak for my UIM/LIM, the smell would like be coming from under the hood right? Mine is coming right from the exhaust tip. At least, that's as far as I can tell. It starts in the back and wafts its way to the front of the car.

I'm going to push the car out into the open air and start her up. The wind should help me better locate exactly where it's coming from without the confines of a garage that pretty much hot-boxes the place and makes it impossible to do as such.

Honestly, I'll likely take it to a local shop that specializes in exotic cars (to include the Rotary Engine) and see what they can hunt down for me. I'd rather not take it to the dealership and pay dealer prices.

The smell was coming from the exhaust. I think that the theory behind it is that if you have a leak in the intake side=more air, therefore the computer has to compensate for more fuel... there wont be any smell in the engine comapartment since its sucking in air...

It fixed it for me so I just wanted throw it out there...

Hey, at this point, anything is worth a shot. I'll order some up new gaskets to see if they're the culprit.

Ok, more info. I drove it a bit.

Because I wasn't in the garage, I was able to see exactly how long the smoke comes out. And it's constant. Ran it for 10 minutes in the driveway and it was putting out smoke the entire time. However, you wouldn't really notice it unless the car was still. In motion, you wouldn't notice it.

When gas is applied, the smoke get's thicker for the duration that gas is applied. It's a white smoke. However, when gas is initially applied, you see a nanosecond spurt of black smoke followed by continuous white smoke. The car was sitting there for a month. I don't think it's simply condensation burning off. Unless there's an crapload of water in there. I may try adding more gas into the tank to dilute any water buildup that may be around.

The car no longer goes into a goofy idle when shifting. The clutch switch was the culprit there. However, the car still goes much more bonkers when you give her gas and let off than I once believed it to. Driving it helped figure that one out. Regardless of what gear you're in, when you let off the gas, the car drops down to the 300-500RPM range and almost dies. But it never fully dies.

Under the hood, coolant is now coming out from under the pressure cap and it's boiling off. I didn't notice that before due to poor lighting.

As well, I just identified that there is a gurgling noise (like bubbling) coming from under my UIM. Reading over some other post briefly on the subject - air in the coolant lines?

My father came by and said the exhaust smells like a combination of normal exhaust and burning coolant. However, he has no idea about the idle.

Outside of the idle when the throttle is let off, there are no other issues with the car in terms of idle or vibration.

I'm not registering any coolant leaks anywhere. Not that I can see at least. This gets more and more confusing as time goes on.

More stuff. There's no radiator coolant in the car. None. I pulled the dip-stick out and it was bone dry. Also had this muck growing all over it. Like caked up dirt and oil mixed together or something. Time to flush the radiator.

Amendment to the post. They got this "you can't edit a message for 30 minutes" thing that's preventing me from changing my above post.

1) Opposite of what I said, when gas is applied ~ the smoke THINS - not THICKENS.

2) There is coolant. Just none in the tank just above the passengers side headlamp.

3) There is a strong odor (that smells like what's coming out of my exhaust pipe) coming from somewhere between the alternator and the UIM. (That's where the smell is the strongest.) It's there regardless of if the car is operating or off.

you fixed your clutch switch no need to address that.

save your money you need a motor

https://www.rx7club.com/3rd-generation-specific-1993-2002-16/results-not-flushing-your-coolant-686776/

Actually, we just found the problem. My brother came over (he's a mechanic) and did his thing. My secondary fuel injector is what's causing the bubbling sound under the UIM.

I walked in to this whole ordeal assuming I would have to change the FPD, Fuel Pump, rails, and/or injectors.

He said that's what is causing the strong odor right under the UIM, and is likely causing my idle issues when I give it some gas and let off. Even with the UIM on, I could physically see the secondary fuel injector with liquid coming out where it seals.

I guess I'm lucky the engine never caught fire. Same for the previous owner that ignored it for so long.

you still haven't addressed the coolant smell or the missing coolant.
You could try tightening the housing bolts but that requires dropping the trans. but no where likely to fix your problem.

Rebuild yours or get another.

yes do the fuel line stuff and send the injectors out for cleaning.