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-   -   What happened to my car??? (https://www.rx7club.com/1st-generation-specific-1979-1985-18/what-happened-my-car-32034/)

clean 11-12-01 11:12 PM

What happened to my car???
 
Hey, I just had something wierd happen to me the other night. I was reading BoominRX7's thread, and I seem to have a similar problem, but it's different enough that I think it might be a different problem. I was driving in second gear, around 5-6000 rpm, getting a fair amount of power, and suddenly I just lost all power. It now accellerates like a ford tempo pulling a space shuttle! Not much get up and go!
I have an '83, with a header, one cat, and no air pump. I thought it might be a severe vacuum leak, but I just changed almost all of the hoses a short while ago. Also new plugs and wires.
After the problem, it started idling around 1000 rpm, which is actually a little higher than normal (not a big deal) but it sounded REALLY deep, no chainsaw on steroids sound. It was kind of a clug-clug-clug sound. It also revs REALLY slowly, when I give it gas it takes forever to speed up.
Any ideas?
Any help is greatly appreciated!!!

Clean

vic'srx-7 11-13-01 01:57 AM

I have some good news and some bad news...... ok mostly bad news. Try putting a little atf into the rotors this will temporarily raise the compression. Try to start the car if it runs better I would suspect that you have lost an apex seal (not good) I would also check to make sure that all of your new hoses are still intact. I have found many times a car that I fis runs worse when I'm done
:rolleyes:. Just spray some wd 40 around the vacuum lines. Your idle should smooth out.
If none of this works I would get a compression check done and cross your fingers.

What the hell you wanted to get that street port done anyways.

Vic

clean 11-13-01 11:57 AM

Couldn't you just say it's a clogged fuel filter or something!!! :)

I hope it's not an apex seal, I was planning on rebuilding the engine next summer, but that's still a ways away. I'll check the vacuum lines, but now that I think about it, you're probably right about the seal.
Hey, is there a chance it could be some kind of timing problem? (Anything but a seal..)

zyounker 11-13-01 12:04 PM

Your cat could of died...


Your idle will not normaly raise when you chuck a seal out the exhaust. it usually wont run...


If it has a really stable lumpy idle, it would make me think that you are running really rich...



-Zach

clean 11-13-01 12:10 PM

Well, before it went bad, I had trouble starting it, almost like it was flooded all the time. I have felt like I've been running rich. I don't understand though why it's all of a sudden gone like this. I don't think it's my cat, I seem to have a lot of flow out the muffler, I doubt it's clogged. (Although I am new to this)
I just checked the vacuum lines with WD 40, they're all fine.
If I'm getting way too much fuel, what do I do about it? It's obviously not my filter, it's a k&n and it's practically new (maybe 500 kms).
Could I have fouled a plug? Could it be timing? I don't want to think it's a seal, I'd rather live in denial than believe that! :-) Although if it is a seal, I guess I'll have to eventually accept it and deal with it..

RXcetera 11-13-01 12:12 PM

If your car is idling HIGHER than it used to, I seriously doubt you've got a apex/corner/side seal problem. Every engine I've ever seen with a blown seal had a very hard time keeping any kind of idle. I'd look at those hoses for a vacuum leak. Make sure your secondaries arent stuck open or stuck closed when accelerating. Turn the ignition to "on", remove your aircleaner lid and look inside the carb to see is gas is dripping out of the stacks and into the engine. It should be totally dry in there if the car isnt running.

zyounker 11-13-01 12:12 PM

Do a compression check.. That will tell you for sure...


-Zach

clean 11-13-01 12:56 PM

Hey,
I checked the hoses, they're fine, I soaked them in WD-40. I'll look inside the carb to see if it's dry or wet. If it's wet, what's the problem?
I think I'm also going to pull the plugs on the off chance that somehow I fouled one.. in a big way! Who knows.

clean 11-13-01 12:57 PM

As for a compression check I'd have to get it up to the dealership, and pay to get that done.. I'd rather not do that until I've exhausted all other possibilities. I hate paying money just to find out what the problem is. It's hard enough paying money to get something fixed, let alone when they just test it! :p

RXcetera 11-13-01 01:08 PM

Check the plugs, but normaly a dead plug would cause the engine idle to drop, not raise. Overflowing your float bowls is what causes the carb to "drip" internally. You can check your float levels by again setting your ignition to the on position and checking the sight glass on each side of the carb. The fuel seen through the glass should cover about half to 3/4 of the glass. It's sometimes hard to see the level, so it's a good idea to shake your car a little while checking.

zyounker 11-13-01 01:11 PM

No, go to your local auto store & spend ~$20-50 and buy a compression gauge. pull out the schnyder(sp?) valve.


Pull the fuse for the fuel pump( i think it might be the one labeled engine)
Pull out the 1 of the spark plugs on the front rotor housing & screw in the compression checker. have someone turn the engine over and watch for 3 even bounces.. (Even in Pressure & time between the bounces..)

Repeat that on the rear rotor..




Or if you don't want to buy a guage just do the same thing as above. You of course won't be connecting the compresson checker. Listen for 3 even wooshes that are evenly spaced...


-Zach

clean 11-13-01 01:29 PM

Hey Zach,
I thought a conventional compression tester didn't work on a rotary engine. I was under the impression that I had to take it to a shop to get them to do it.

RXcetera 11-13-01 01:30 PM

No? lol. What's up with that?

clean 11-13-01 01:32 PM


Originally posted by RXcetera
Check the plugs, but normaly a dead plug would cause the engine idle to drop, not raise. Overflowing your float bowls is what causes the carb to "drip" internally. You can check your float levels by again setting your ignition to the on position and checking the sight glass on each side of the carb. The fuel seen through the glass should cover about half to 3/4 of the glass. It's sometimes hard to see the level, so it's a good idea to shake your car a little while checking.
To be honest, I'm not even sure where the sight glass is. I'll have to look for it.

Here's something I just found out, I pulled all four plugs and checked them. The front two are fine, they look good and they're dry. The two plugs for the rear rotor are black and wet. Would this be any indication of a problem?

zyounker 11-13-01 01:35 PM

RXCentra: i was actually talking to him. You hit reply before i did though :)


You can use a standard compression tester.. It will tell you if you still have compression.. it is not as acurate as what the dealer uses but it will help you diagnose this problem..

Also as RXCentra said the float level will cause your discribed problem..

if you are running to much fuel pressue this can happen too.(if you didn't upgrade your fuel pump that is not it though)


-Zach

RXcetera 11-13-01 01:35 PM

You're looking for even pulses on each rotor. 2 good pulses followed by 1 weak one means bad corner/side seal. 1 good pulse/2 weak ones means bad apex seal. I still stick by my theory though... an engine with a bad seal should not have an increased idle.

clean 11-13-01 01:44 PM


Originally posted by zyounker
No, go to your local auto store & spend ~$20-50 and buy a compression gauge. pull out the schnyder(sp?) valve.


-Zach

Okay, bear with me guys, what is the schnyder valve and where is it, and how do I pull it out?

RXcetera, I think I'm going to run out right now and check the float level. If this is it, I hope it's not a big deal fixing it!
:)

RXcetera 11-13-01 01:45 PM

Hey, that's important info Clean. Something is up with your rear rotor. Try flipping the bottom plug for the top one. Check the carb throats for rotor 2 (toward the back of the car) for flooding. That plug is wet because it isnt igniting properly. This can be cause by a bad plug, too much fuel that is drowning it or... gasp... a bad seal.

zyounker 11-13-01 01:48 PM

I don't think it is a bad seal either RXCentric.. But that is a way to eliminate that possibility...

I am thinking your ignition is screwy.. put a different/new plug on the wire for the rear housing & check to see if you are getting spark on that plug..

BTW do not hold the plug while you turn the car over or you will get knocked on your but..


-Zach

clean 11-13-01 02:00 PM

Hey, I just checked the glass window on the front of the carb. I couldn't see the one on the back, which is probably the one I want to see. It was filled about 2/3 of the way. It's all dry inside the carb when I take off the air cleaner and turn the ignition to the on position. I don't really even smell gas. I'll check the plug, when I get someone to give me a hand, I can't turn the key and check the plug at the same time, I'm not that coordinated. Wow, I sure hope it's the plug!!!!!!!! That would be awesome!!!!!!! The dealership sells the plugs the cheapest around here, and they're just down the street! Thanks guys, this REALLY helps!
It's not fixed yet though, and I'm not sure this is the problem, so any more info would be greatly appreciated. Also, I still haven't done the compression check, where is this schnyder valve that I need to pull?

clean

zyounker 11-13-01 02:12 PM

IT is usually in the tip that connects to the sparkplug whole.. It usually looks like the inside part of a bicycle tire stem...

Some have a little button that lets the pressure out. if you get one of these you can just hold the button open usually..

-Zach


The rear float is the one you want to look at.. Maybe get a mirror?

clean 11-13-01 02:18 PM

You mean the schnyder valve is the little silver coloured tip on the back on the spark plug that just threads off?

As for the float on the back, I'm not sure I have a small mirror, I'll have to look around the house.

Felix Wankel 11-13-01 02:24 PM


Originally posted by clean
You mean the schnyder valve is the little silver coloured tip on the back on the spark plug that just threads off?

As for the float on the back, I'm not sure I have a small mirror, I'll have to look around the house.

Schrader valve is the valve in the compression gauge line, it keeps the air from escaping. Take your valve stem cap off one of your tires and look at the valve stem, the thing in the middle is a Schrader valve.

clean 11-13-01 02:58 PM


Originally posted by Felix Wankel


Schrader valve is the valve in the compression gauge line, it keeps the air from escaping. Take your valve stem cap off one of your tires and look at the valve stem, the thing in the middle is a Schrader valve.

Okay, so since I won't be checking with a compression tester, I won't have to worry about it, thanks.

clean

Rotary_Rocket_Guy 11-13-01 03:32 PM

Take out one of your spark plugs and look at it then smell it, if it looks wet and smells like gas then the spark plugs are probably flooding, because I had the same problem only it happened to me while idling.


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