liebherk

http://youtu.be/JcXL7zf1eQU

I've had it happen in the past where it cranks and won't start for a while (misfire?), but it eventually does. I was poking around trying to diagnose a coolant leak, and it's been sitting for about a week, now this.

What's going on? It sounds like it's not even firing.

RotaryRocket88

iTrader: (7)

I'm not sure if it's just the video quality, but I don't hear the distinct sound of compression. You can pull a spark plug, then crank the engine to do a "poor man's compression test". The use a gauge with the schraeder valve removed will give you real number to work with; you should see 3 even pulses per rotor around 90 psi or higher.

Check the spark plugs for gas to determine if you're getting fuel.

Pull a spark plug wire out a little from the coil (or use an inductive timing light) to see if you're getting spark.

HotdorkboiRX

You can pull vacuum line loose and poor transmission fluid in it. The rotor tips are dry and need to have fluid back in it to run correctly. Poor the fluid in any line that goes into carb or engine. Crank a few times before letting the car turn over all the way. This dips the rotor tips into the fluid you just put into the engine. Remember it doesn't take much to oil the tips so do not put a whole bottle in the engine.

You may also need to pull the engine comp. relay out of the engine relay box located on the drivers side fender under the hood. Pull this and let the car set for 2 mins. After doing so crank the engine no more than 3 times. This will reset the computer and makes it think all fuel and oxygen mix is at 0. Replace the relay and the car should start. You may have to do this a time or two.

I have bought a few RX-7's that people say are not functioning and are dead and this was the only problem. This is a really common problem in the 2nd gen. models. On 1st gen. this the engine comp relay was set up differently and 3rd gen. the system was redesigned.

Hope this helps.

RotaryRocket88

iTrader: (7)

Fuse not relay. Relays are something completely different. The EGI COMP and EGI fuses may be pulled, then the engine cranked over for ~10 seconds to clear a flood, but that may not be the issue. It's not done to "reset" the ECU; it's done to prevent fuel injection while you crank the engine.

Adding a little oil via a vacuum line or squirted through a spark plug hole would aid compression if the engine is badly flooded & gas has washed most of the oil away. But it won't do much if the engine actually has low compression. Still, it's a good suggestion if the engine is just really flooded.

liebherk

Hmm, I don't know how to do any of that... lol.

I'm guessing it's better to try the flooding solution first since it's simpler?

liebherk

I guess I'd better make it clear that I don't know much about all the specifics and parts of how cars work. For instance, I have

no idea how to identify the vacuum line or if you're talking about the vacuum line that goes to the fuel injectors, brake booster

or whatever else uses a vacuum line. (I assume you mean to the engine, though.) That's not to say that I'm a complete idiot, I

went to school for mechanical engineering, I just never took the time to actually take apart a car and really learn every single

part and how everything works together.

Basically, RR, you seem to talk as if your audience already has a thorough knowledge of automotive workings, which is not the case

for me... it seems like you assume or take for granted things I have no idea about. Though If your goal is to get people to do

some research for themselves so they can actually translate what you're talking about, then mission accomplished.

Anyway... What do you mean by check the spark plugs for gas? This?http://www.ifixit.com/Answers/View/4...+plugs+are+wet

+with+gas

"A wet spark plug means the plug has not been firing. If not due to engine flooding, the problem may be a bad ignition cable

(excessive resistance, shorted or arcing). But wet fouling can also be caused by dirt or moisture on the outside of the plug that

provides a conductive path to ground, or by an internal crack in the ceramic insulator that shorts the plug to ground."

When you say 'pull a spark plug, then crank the engine to do a "poor man's compression test". The use a gauge with the schraeder

valve removed'

Do you mean doing this
http://video.google.com/videoplay?do...31118552786754
with something like this?
http://www.searsoutlet.com/Compressi...de=buyUsedOnly

Does this video apply?

http://youtu.be/064Ilsz8Fzg

(I like this guy btw, the way he explains things is clear and easy to understand for a noob like me)

RotaryRocket88

iTrader: (7)

Engines produce vacuum at idle. You can use the vacuum to suck oil into the engine. Search "vacuum diagram", or look at the fuel/emissions section of the FSM, which is free online. Links in the 2nd gen FAQ. Just about any vacuum line on the engine could be pulled temporarily to suck oil in.

This is a car forum. 99% of the people here at least have some basic car knowledge / how an engine works. If you do not, then yes, it would be a very good idea to go ahead and search the forum heavily. Everything that I have said so far can be searched for on the forum to find more in-depth information. I can't always spell everything out, and whining about the information that I did give you is not going to help. If you made this very same thread in the 2nd gen section, you would basically be ignored or told to take your car to a mechanic.

If the plugs have gasoline on them, you're getting fuel, but not spark (or it's just really really flooded). That's it. Plug color is not a concern. That would tell you how the fuel is burning (lean or rich), which is not relevant to your problem.

Yes. The "poor man's" test I mentioned earlier is just removing a plug, cranking, then listening to the sound of the pulses. If they sound uneven, it could point to low compression, but a gauge is a much better method.

liebherk

Sorry for whining. I guess I was trying to say I'd appreciate it if you dumbed it down/pointed me in the right direction just a little more. The search terms helped a lot.

So I pulled the EGI fuse and cranked it for at least 10 seconds (ha) several times and it didn't affect anything.

After typing that I actually just found this page, though: http://www.rx7.com/techarticles_unfloodFC.html And it looks like I didn't do it quite right if that's exactly how it has to be done. (Didn't depress the gas pedal while cranking it) So I'll do that tomorrow.

Then I did the poor man's compression test according to the instructions from here:http://aaroncake.net/RX-7/blown.htm (except I forgot to do it with a fully charged battery. Actually the battery was rather drained from trying to start it a lot.)

http://www.youtube.com/watch?v=m9CNnRA7VfY

It sounds normal to me.

Then I checked the spark plugs. The trailing one in the forward rotor had a little debris in it, looked like metal shards. Also it didn't look like it was getting much gas compared to the leading one. I also discovered that one of them wasn't sparking. I don't remember which one it came from but I replaced it with a fresh one. The rear rotor's both got plenty of gas.

boostaddictB89

sounds like no compression, a quick way to find out is open the intake manifold and squirt a little auto trans fluid inside, if it starts up then , then its a compression problem due to your apex seals. hope this helps man

RotaryRocket88

iTrader: (7)

Where on the spark plug was this metal debris you found? On the threads, or on the tip near the electrode? If it's on the tip, it came from from inside the combustion chamber, which would pretty much mean it's part of a seal. Not good. If it's on the threads, it could be the result of cross threading.

I'd rent a compression tester from the local auto parts store, and also try to find a syringe or something similar to squirt a little oil in through a spark plug hole. Get enough oil in there, and even a blown engine will start.

As for the lack of spark on one plug, figure out which one it was. The leading plugs are batch fired at the same time from one coil. If the coil fails, neither will fire, and you'll never get the engine started. The engine can start and run without the trailing plugs, which fire separately. Plug wires can also fail.

liebherk

It was on the tip near the electrode. It may have just been gunk, I only touched it to brush it off and I barely felt it so it might not have been metal.

Anyway, I got it started by just doing the deflooding procedure correctly with a full battery charge. I had tried for a while yesterday with no luck, but today it started right up on the second try. I discovered that when I was trying last night, the spark plugs weren't connected on the rear rotor... lol. Pretty sure they were when I tried earlier in the morning, though.

Thanks for the help!

boostaddictB89

glad to hear you got it running

o5rx8mazda

iTrader: (1)

sweeet man!!! im actually having a similar problem with my FC! i removed the UIM to fix a fuel leak, and i put everything back together and it began to have starting up issues, and would smoke. soo i removed everything to check for leaks and i found that the injector harness was reversed!!! soo i switched it back, and it started up on the first try no hesitation, but when i let it sit overnight it wouldnt start up and just kept cranking, and wanted to start but would oonly start if i pressed the gas pedal.. anyone have this issue before???