XLR8

iTrader: (52)

Last week I bought an Accel coil for the leading. It made a nice difference and I have been enjoying it. Last night I drove my car for about an hour parked it for a couple hours and when I came out to start it again it was missing. I have experienced ignition problems before. I am completely stumped. This is the overview of my problem.

Symptoms:
It is missing. It will barely idle sometimes, but it's at like 100 RPM. It doesn't backfire badly but there is a puff every now and then while revving. If I hold the throttle steady at any RPM it misses fairly bad. It does rev normally and quickly. If I hold the throttle steady to a lower RPM it misses real bad. It doesn't miss in long violent strokes, but it misses light and rapidly. It almost acts like a sticking shutter valve, but mine is removed. The deceleration is slow and it seems to be slower in the lower RPM. The car does make power. Doesn't quite feel as strong as normal, but it does pull strongly. When I hold the throttle steady and start to increase it slowly the RPM's jump in short spurts. Almost like it clears up and rev's normal for split second.

What I have tried:
All plugs are getting spark. It is a yellow spark. I don't know if that is considered week or not. I have checked the timing on both leading and trailing. I have swapped the distributor with another that had all different igniters, cap and rotor. I have swapped both the Accel leading coil and the trailing with a known good stock coil. I have a set of RB red wires but I swapped them with a known good set of wires. I tried adding ground straps to the firewall, engine and battery. .
The only thing I haven't tried is new plugs and I'm going after them tonight.

What it has:
Removed rats nest and air pump, blocked ACV, removed shutter valve, reman stock nikki, RB Red Wires.


I have a fairly new fuel filter but I just don't think it's a fuel issue....

Any help is much appreciated.

trochoid

iTrader: (6)

Put everything back to the way it was before you swapped in the Accel coil, then go from there. Be sure to check all of your wireing connectiong, both for corrosion and tightness. Also make sure the dizzy cap is sitting on the dizzy straight and check the contacts inside the cap. It's quite easy to knock the cap askew, then the rotor will take out the contacts inside the cap.

XLR8

iTrader: (52)

I have swapped back the original coil. I have checked the connectors on both coils and cleaned all connections relating to the ignition. I am beginning to think it's a bad connection in my wiring........??

Also, there is a small metal barrel type thing that is attatched to the distributor between and slightly below the two vacuum advance diaphragms. It has a single wire going to it. Anyone know what it is....???

wecycle

It is a condenser (capacitor)

Rx-7Doctor

iTrader: (13)

And so when you go to ask the question. Does the capacitor have any affect on power? The answer is no.

mcw3

You say the deceleration is slow- meaning it's not coming back down to the idle properly? And sometimes it doesn't idle high enough? Vacuum problem maybe? When was the rat's nest removed?

Kentetsu

Yeah, definitely take a hard look at the vacuum lines and make sure you haven't knocked something off somewhere... You didn't end up switching the lead/trail ignition around on accident during your install did you?

XLR8

iTrader: (52)

Thanks on the capacitor. I have everything set up properly, the leading coil is closest to the firewall. I thought maybe a large vacuum leak too, though my instincts tell me it's a spark problem . I only have 2 vacuum lines, one to the vacuum advance and the big brake booster line.

I was having a problem with my AVC blockoff plate sealing completely, I recently used RTV red and a home-made cork gasket to try and fix the problem but it still leaked a little. I will pull it off today to see how it looks, after I install the new plugs.

The rats nest has been removed for about 6 months. The rev's are unusual. You know what a rotary acts like when it's running on one rotor. Rev's up and down slowly, won't idle, and has a strong miss. My car is acts much like that but on a smaller scale. It makes power and will rev quickly, but when the tach comes back down it hangs a little more then normal and when it get's to about 2k it slows down even more. If I hold the throttle steady at 3500 RPM then there is an aparent miss, but if I hold the throttle at a lower RPM, say 1500 it misses very rapidly, and the engine shakes.

This sucks.......
Thanks for your help guys.

XLR8

iTrader: (52)

Just tried the new BR8EQ's and nothing changed. I ran it for about 20sec. then I pulled the plugs out to put in the new. I noticed that the leadings were wet with gas.

I also just checked continuity on all the wiring from the alternator, igniter's, and the coils with no luck. They all have connectivity.

My friend thinks it's a fuel problem......stuck float maybe..

I took it for a drive and apart from the bad miss it runs strong and pulls hard.

Kentetsu

Did you check to make sure that the dizzy cap is on straight? Look inside and make sure that the terminals aren't all chewed up or burnt. It's very easy to get the cap on a little crooked and then it tears things up a bit.

Maybe check your grounds too. If the engine doesn't have a good ground then it can have problems keeping spark.

Are you sure you haven't lost an apex seal?

wecycle

If the capacitor is failing by grounding out you might get the symptoms you describe. Test it for continuity or remove it and see if anything changes.

XLR8

iTrader: (52)

The cap and rotor are both straight. I have installed grounding straps from the engine, firewall and negative battery terminal.

It's funny you mention the capacitor. I did notice the wire running to it was extremely bridle. I will check it out. Also, the distributor that I swapped in did not have that little capacitor on it. When I tried it with that distributor I just let the wire hang. I will investigate further.

I am going home to WV this weekend. I plan to grab another distributor, carb and manifold, and any other part I think could help diagnose this problem.....

Thing is kicking my A$$.

Thanks again, for all the help guys.

XLR8

iTrader: (52)

Pulled the wire off that capacitor and it did nothing. I was also contemplating a problem in my ignition switch wiring. If there was a short or bad connection there, it would cause intermittent igniter firing......

It's pissing the rain down.... I will have to try later.

XLR8

iTrader: (52)

Can someone check the voltage on their coils while the car is running? I checked mine and they were 1.7v and 1.9v. I don't know if this is normal.......

Really starting to think it's a fuel issue.

Jeff20B

iTrader: (13)

It's gotta be a carb/fuel issue.

XLR8

iTrader: (52)

Just double checked the timing. It is dead on and it is not missing a beat.

XLR8

iTrader: (52)

Just performed a compression test.....90psi in both rotors..... at least that's some good news...

I am going to have to agree Jeff20B. From the symptoms it has, I don't think it's a fuel starvation problem but rather a mixture problem.

Anyone know Sterling's site or how to contact him about a worked carb?

Thanks guys!