Razmus

iTrader: (2)

K Im going to do this cliff notes style, with symptoms and what i have tried. So before you go smashing on my thread, please aknowledge that i have tried some ****. so i will do it this way, one, because it will be straight to the point, and two, because its easier..

Car:
1987 RX7 Turbo II

Miliage >58,000

Mods:
-Boost guage
-Racing beat Y pipe
-Wierd dual exhaust tips (brand unknown)

-We hooked up an MSD ignition box but removed it like two days later. car was running fine.


Problem:
-Car will turn on but will shake violently in idle
-It seems like there is no spark as car shuts off within two seconds without pressing gas
-When you push the gas and actually keep it running, it wont boost till 6K
-Once it shuts off, next time you try to turn it on, its flooded.
-From time to time the tach will not read

What Ive tried:
-Checked for boost leaks
-Checked for vaccum leaks
-Changed spark plugs
-Changed spark plug wires
-Tested the coil and igniters with a multi-meter. They are within spec according to the repair manual
-Tested the plug wires and they have resistance
-Checked the ECU, still working fine
-Checked and replaced the Crank Angle Sensor (maybe whats messing up the tach??)
-I took the EGI fuse out and disconected a wire from the spark plug. I hooked up an extra spark plug to check for spark and only ONE out of the FOUR fired. The spark plugs have about 5K miles on them. I took them from my DD and are NGKs.

Questions:
-What should i check next?
-When i checked the OHMs in the Crank Angle Sensor, it read OFL....so i installed the new one, but again nothing happened. Whats making it do this?


I have narrowed it down to being something with iginition, due to the fact that only one spark plug fired, and it gets flooded very easily. I checked and replaced the CAS which would be responsible for telling the coils to fire....right? at this point Im ready to throw the multi neter through the windshield....

Any help is and will be appriciated.

Icemark

Compression?

Razmus

iTrader: (2)

Have not done a compression check but when it is turning over it sounds fine. I have an S5 NA that just blew a rear rotor so I remember that it sounded different. The TII sounds strong.

George84

First off I really like the way you gave the info. You only have one spark plug firing? Let me think on it....

Razmus

iTrader: (2)

Thanks, Im tired of people posting novels on simple issues....

wtdpn115

did u put a different type of crank pulley on? or did u pull the crank pulley off?
sometimes the lock pin doesn't get put back in aligned correctly it would cause the counter weight to go whackie
curious how did u check the ecu? borrowed one? or have a spare?

HAILERS

So now you have a spare CAS.

Take that spare CAS and connect it to the harness but do not install that CAS in the engine. Turn the key to ON. Hold that spare CAS in your hand and spin its bottom gear with your fingers while watching the two LEAD sparkplug wires laying on or near the left strut tower studs.

Your looking to see if both are sparking as you spin the CAS.

Ignore the TRAIL coils/plugs for now , OTHER than making sure that you have T1 on the front top plug and T2 on the rear top plug.

On the other hand, it takes but fifteen minutes to pull the bottom two sparkplugs out and have someone spin the engine while you put your finger over one hold at a time and compare the pulses. If it's a bad apex seal it will be very noticable and no compression tester is needed to figure that out.

And by the way, both Lead sparkplugs fire at the same time. One cannot fire without the other having fired.

Icemark

Means nothing.

Flooding is most commonly caused by poor compression. So when you say you have poor idle and flooding, compression is the first thing I would check.

I would also be looking at spark as mentioned, but of your motor needs rebuilding, that should be done first.

skatingsamurai

pull off one of your vacuum hoses before during or after start up. what does it smell like?

oh. and you def. should do what hailers suggested. kills two birds with one stone.

hhn2002

hmm well from my understanding the cas tells the ecu the rpm and from there the ecu tells the coils when to fire.
if memory serves you can use the multimeter to check resistance in the coil but to check the ignitors that requires a special diagnostic tool from mazda. try swapping out ur coil/ignitor assembly with a known good one.

good luck