basically what happens is, say your window is all the way down. "Ok its cold in here, I'm going to roll my window up!" you hit the window button and hold it until its all the way up. Right as its finished rolling, theres like a surge, and the car shakes a lot for a second.

I googled this issue and it looks like some people have said it is the torque converter in their car and it is being temporarily fooled by the output of the engine.

Looks like people are deciding to live with it because it is such a pita to change. I mean I guess as long as its not something is dying...

 

I have a 2004 rx8 with just over 33000 miles and was having starting problems, so i took it to the dealer and big surprise I had to replace the spark plugs, ignition coils, ignition wires, and the crankshaft position sensor (not sure about the sensor name exactly) and about a month later I am having the same problem. it cranks but sometime hot or cold start it just takes 3 tries to get the engine to turn over (after cranking for about 5 to 7 seconds each). The check engine light turned back on so i took it to the dealer but when they turned it on, the light had gone off so they couldn't figure anything out :/ any guesses?
I'm pretty sure it is not the starter. I have looked at a bunch of videos on youtube about the starter and hear a weak starter...mine sounds strong. When i turn the car off, every time...I rev it up to 3000 rpm and hold it there for about 2 or 3 seconds and then let go of the gas and turn it off at 1500 rpm (while still going down). could this be the cause of my problem? if not...any ideas? thanks!

 

did you pull your battery? the CEL should have remained in the cars memory...

Also you dont need to rev it when you shut it off, only when the engine is cold and you have no choice but to shut it off.

 

i checked the power from the battery and it was giving 13.6 volts...strong as hell. and i cleaned the terminals. and ok good to know about the reving

 

Diagnosing a car problem on line is kind of like reading up on a medical issue. Your symptoms can fit a lot of things and not be that problem. You have already spent a good amount of time/effort replacing motor mounts which apparently was not the problem. Torque converter is a mechanical part. What you seem to be describing' is coming from some sort of electrical feedback. In today's cars the computer controls a lot. My recommendation is to find a mechanic with a modern diagnostic computer. This may not need to be a dealer. My son runs a Mitsubishi Eclipse, we had the engine rebuilt and the shop that rebuilt it spent two months trying to get it to run with no success. They finally took it over to another shop that had a sophisticated diagnostic computer and figured it out. In this case it was a wire coming from the crank sensor that was corroded.

All I can recommend is put some money into a good diagnosis prior to putting any more into actual repair/replacement.

 

[QUOTE=EricB;4377683]did you pull your battery? the CEL should have remained in the cars memory...

Also you dont need to rev it when you shut it off, only when the engine is cold and you have no choice but to shut it off.[/QUOT

Did it run great AFTER the dealer did what they did or was the issue sporatic enough that you can't really tell? I would have a good discussion with the actual mechanic. Let them know that none of the things they did fixed the problem. Not saying that crank sensors and coil packs DON'T go bad, but you should not need to spend good money for them to guess at what the problem is. Both the sensor and the coil pack can easily be bench tested to see if they were bad, or even weak

See my above post on finding a shop with a sophisticated diagnostic computer. Replacing parts until you find the problem is a poor way to really fix something.

I know we are somewhat at the mercy of the shops to tell us the problem, but you should not have to pay for their guessing.

 

catch- yeah thats what i argued with them so i took it back to the dealer because the problem happened again and the said they would look at it. so when it happened again (just a second time(first time after the new plugs wires etc..)) the check engine light came on so I dropped it off as soon as i could and when they turned it on they said the light had gone off and they couldnt do much without it. so they kept the car for a few days starting it both cold and warm starts trying to repeat the problem and it didnt happen. i just got the car back today. i haven't driven it much yet but it seems fine now :/ idk! before the $1400 of work on spark plugs etc... it was very bad and happened 3/4 time i started the car. they did a compression test and it is holding fine. im just not sure. i think there is something wrong but there is a possibility that it was caused by me revving it when it was warm before i turned it off. that could have been a problem causer, but i'm not fully convinced. i guess i'll have to see withing the next week or so

 

I have been revving my engine to shut off for about four years now. Never had any issues and never been flooded since. Before I started doing this it flooded twice. Just a precaution for me. Yeah it wasted fuel, but better than being stuck when it's your only car.

 

If what they fixed was the problem. It should not happen again. If you find it continues, be polite but clear with the dealer that you are not satisfied. Ask to talk to the shop administrator, director or whatever the title of the person that is in charge of the shop. Tell him the specific issues. Let him know that you have already had the car in twice and spent what most of us would consider a pretty fair amount already. As I said, at this point be polite, but do ask for a business card and when done, jot down date, time and what was told to you.

Ask if they put the car on the diagnostic computer. If the did, they should have some documentation of what it found. Also ask up front about any costs for this visit. Should not be any, but I would not have an issue if they charged for a legitimate part if they do a correct diagnosis and do find some sensor or other issue. I would want the them to cover labor.

This is the next step. If not taken care of to your satisfaction, there are others.

 

Check all connections to the starter. I had a similar issue which turned out to be that the nut connecting to the bolt on the starter (the one protected by the plastic case) had vibrated off and was barely touching. It caused a 50% chance of starting all the time. The CEL might have been the code for the crankshaft position sensor. Thats the one I got.

Anyways, I'm not saying that its the issue, but I'd really look at all connections to/from the starter. Even if it sounds strong, it doesnt mean there isnt a wiring issue.

 

I was polite on the phone and simply told them my story saying that they had previously done all of the work and asked them to do what they could to try and find out the problem. They couldn't find out the problem because they could not replicate the starting problem when it was there for about 4 or 5 days (of them trying it cold and warm starts) they said every time they tried, it was a normal start and it worked...so I took the car back.
It has been working fine so far but I have not driven it much yet.

 

Yeah that was one thing that I didn't understand...i know that you are supposed to rev it when its still cold and you HAVE to turn it off and that helps reduce the risk. I'd be surprised if you actually increase your risk of flooding revving it before turning it off when the engine is warm. Logically, it should either help reduce the risk, or just do nothing to change a normal starting condition. That is why i revved it before turning it off even when warm. (btw I have never turned the engine off with the temp. gauge anywhere else besides in the middle and warm).
Having this said, i think that there still is a problem, unfortunately it doesn't happen consistently. I don't think that the problem was me revving it before turning it off. :/

 

Reving before turning off will only make a difference on a later start if
A) The engine is cold,
AND B) the ECU is adding extra fuel (it doesn't for a brief period immediately after start up),
AND C) something about your ignition, compression, starter, or battery makes flooding a possibility.


Starting requires:
- spark (which needs firing coils, transmitting wires, firing plugs, engine block grounding, battery power, battery grounding)
- fuel (which needs fuel injectors, fuel pressure)
- compression (which needs sufficient seal clearances and sufficient cranking RPM (which needs battery voltage, starter speed, flywheel engagement))

What haven't you checked or addressed yet?

 

I am the third owner of the car. one guy had it for like 28xxx miles and the other had it for only a few months to 30xxx miles and then i bought it. I do not know of previous work that has been done to it but I have done the following:
1. clean the battery terminals myself
2. had a real mazda dealership
a. replace the spark plugs
b. ignition coils
c. ignition wires
d. crankshaft (or cranking) position sensor (im not sure about the exact name)
3. Mazda did a compression test and it held compression well
4. Mazda checked the battery, alternator, and starter and they all had power and were strong (did not need to be replaced)

 

So, there has been no mention of the grounding points, fuel injector operation (either electrical, leaking, clogged, etc...), or fuel pump providing good pressure (electrical, old).


And since it was a "real Mazda dealer", unless you have documentation that all 12 pieces of the ignition were replaced, as in it lists 4 coils, 4 wires, 4 plugs, then they may have just "checked" them. Dealers are notorious for just "testing" coils via the Mazda test procedures and telling owners that everything checked out. The problem is that Mazda's coil test procedure will only tell you if a coil is completely and totally dead, when a coil can be failing enough to cause misfires, mileage drop, power drop, idle problems, starting problems etc... and still pass the Mazda test.

I shudder at your $1,400 bill. All 4 coils, 4 plugs, and 4 wires can be had from Advance Auto (yes, OEM) for ~$180-$220 shipped to your door for free (price varies based on active promotions) and changing them is an hour tops if you don't know what you are doing. A compression test is $90 to $180, which a dealer has to do. The battery, alternator, and starter can be tested for free at nearly any auto parts store. E-shaft sensor (same thing as the crankshaft sensor for piston engines) is just a magnet and it actually failing is exceedingly rare, usually just gets dirty, and can be cleaned for free. Failures are usually wire damage leading to the sensor. It's pretty hard to break a magnet.

 

Ok so I've been reading about this so called "premixing" some of you are very fond of, how do I do it? What's the best kind of premix or oil (whatever it is you put in there) to buy? And are there any negative effects from doing this? Also what are the positive effects. Thanks guys!

 

I have noticed that when I stop, I can feel the shift lever move up and down. Not a lot, but noticeably. Is this normal?. I know others have mentioned having motor mounts changed. This car only has 37000 on it.

 

Wow, sorry for another dumb post, I just filled up and checked the oil. First, I noted a lot of whitish foam on the dipstick. This is a bit unnerving as I normally associate this with water in the oil. Radiator is perfectly full, so it does not appear to be that.

Engine oil was changed a few hundred miles ago when I bought it. Not sure what brand used , they said it was a 10/40.

Second thing I noted is how difficult it is to read that oil dipstick. Any hints to make it easier to read. Never seen such a small dipstick. Some what odd given the need to really monitor oil levels

 

Please read through the threads in RIWWP's signature. It will help you going forward and will answer some of your questions.

 

Can someone let me know what this is for?
I was under the car and I saw that this was unplugged

 

That is the oil level sensor - you will want that plugged in ...

 

No wonder my oil light has been on Thanks!

 

Living up to the theme of this post, what does this car sound like without the bigass muffler they have on it. Wow that is a large can.

 

Sounds like a pissed off lawnmower.

Many people have taken theirs to Midas for glasspacks and then deeply regretted it....

 

Sound like good advice. I actually like the sound of the whine of the car you hear from the drivers seat. Each of the cars I own has a unique sound and it is as much a part of what the car is as the bodywork.