chris_stampe

I recently bought a new coil because I didnt an ohm test on the old one and it was bad. I installed the new one and tried to start it up. It did go so I had someone check to see if there was a spark on each plug, and the only one that had a spark was the trailing #1. checked the ohms on all the coils and they all seem to be fine
checked the ohms on the cas and it seems to be good. should I be checking the spark with a timing light? BTW the guy checkin to see if there was a spark probly didnt mess up. I tryed checking the conectors that go to the coils with a volt meter and got somethin like 25 volts ac. I have run outta things to do! I cant figure out whats wrong.

chris_stampe

Anyone? I need help!!

RETed

Are the spark plugs wires in good shape?
How was this guy checking for spark?



-Ted

chris_stampe

I was using my new wires at first but then put the old ones back in thinkin the new ones didnt work. He was just holding the end of the wire near a ground and lookin and listening for the spark. I will try putting a spark plug on the end of the wire and see if there is a spark. But what is the most probable cause of this? Keep in mind i dont have a afm because i have a carberated engine with a k&n intake. Thanks for any help.

HAILERS

So you kept the original crank angle sensor? How about when you took the dymanic chamber off, mabe you forgot to make sure that gang of ground wires that are located left of engine centerline, and just a little aft, are grounded(ECU grounds). The wires are gathered together in a round lug that fits under a bolt. Just a thought. I think I'd go to the ECU and do a continuity check on the wires that go to the cas. Also check the LEAD COIL ASSY little white plug. Should have 12v on the black and yell0w wire. This car should start with just the lead coil or just the trail coil assy. If you need a wiring schematic write back and I'll post one for you.

chris_stampe

a wiring diagram would be awesome. the haynes manual doesnt seem to have one. or does it?

MasteRX

Go here, it is a '88 factory service manual in PDF format:

http://www.iluvmyrx7.com/Technical_I...ice_manual.htm

HAILERS

Its probably fixed by now. I forgot about doing this. Here's a jpg:

HAILERS

coil two jpg: I also put some jpg of the ECU output pins on this thread: https://www.rx7club.com/forum/showth...threadid=59266

chris_stampe

Well now ive got both trailing plugs firing, but the leading 2 still are out. The coil is good. There is an ac signal coming into the coil. Theres also a 12v dc coming to it on the black wire. The two wires coming from the ignitor to the coil also have a dwell reading. the dwell is higher on these wires than on the trailing coils. I am near positive that it cant be the plug wires or the spark plugs, all that it can be is the coil or the ignitor and the coil checks out and i have tryed two different ignitors. The only other thing it could be is that the signal from the ecu is bad. Is this probable? Thanks for any help

copandengr

One thought...The factory manual states that if the coil/ignitor assy. is disconnected with the battery hooked up damage to the ignitor will result. It does not say what damage will happen or why.

The negative battery terminal should always be disconnected before removing any of the coil wires, except for the plug wires.

HAILERS

Here's a jpg out of the manual talking about inductive timing lites and the Lead wires. So I'm saying maybe to check the lead wires you should leave one wire hook to its plug and the other close to a stud on the strut tower or someother ground and look for spark. Thats if you're using an inductive timing lite. I just know the black wire with a yellow stripe should have 12v dc and the other wire should have approx 5v dc that comes and goes to trigger the coil. EDIT: OH DARN. SCANNED THE WRONG ITEM. I'll GO FIND THE RIGHT ITEM AND SEND IT LATER.

HAILERS

OK. I have some more egg on my face. The book does not exactly say what I said in the above post. Anyway I have noticed, and others on this site also, that when viewing the lead wires using a timing lite, there will be long pauses of no flashes at all, and its not that the ignition is corrupt. It has something to do with the timing light. If I remember right someone at one time posted a MAZDA bulletin that mentioned this quirk.

HAILERS

HERE: