fredrx7

So thats my problem. Its a ser 4 turbo and I already tried a different coil and igniter with no luck. Also I confirmed power when ign is on at the two prong clip that hooks to it. The body of the coil is confirmed to be grounded as well. Also the connectors look to be okay. I do realize that the tach gets its signal from this coil so I hope that one thing fixes both. No working tach in the cluster or on my safc. I at a loss, can you guys give me some input?

fredrx7

perhaps I should mention its a jdm motor I installed recently. It starts but runs rough.

fredrx7

A little update. Today I tried a different ecu. Car ran but still the same problem. Also I tried another cas for ***** and giggles and as you may have guessed yup still no trailing coil or tach.Correct me if im wrong but the only connectors relative are the one that connects the cas, another connector for those four wires a footish away on the harness, the connection at the eu and the four wire connector at the trailing coil. They all look clean and fine. Am I missing something?
Someone please chime in Im really stumped!!!!!!

fredrx7

should have collected my thoughts more as to avoid the multiple posts, anywhoo...I should maybe also mention that I have a smaller than stock deepcycle battery (made for a civic) thats relocated to the trunk and although its a ser4 car it has a ser5 alternator on it.

satch

iTrader: (1)

Is the engine an S4 or an S5 w/S4 sensors?

Is the ECU the one which came w/the engine or is it a USDM?

Pin 1X, Blue/Yellow wire, reads 0 volts w/key to on and .8 volts at idle.
Pin 1U, Brown/Yellow wire, reads 4.4 volts w/key to on and 2.2 volts at idle.
Pin 1M, Blue/Red wire, reads below 2 volts in either situation.

The Yellow/Blue wire at the trailing coil reads about .6 volts w/key to on.

And are you sure the coil wires are running to the correct positions?

fredrx7

I was hoping you (satch) would chime in! It is a ser4 motor with ser 4 sensors. What do you mean by the coil wires running to the right positions? I have never messed with the wires under the little plastic caps on the coil or those at the ecu other than to tie in my safc if that's what you mean. The values you stated, are those what I should see at the ecu's output to the coil (and thus also at the coil connector hopefully)?
Thank you very much for helping me I'm feeling quite desperate!

fredrx7

And oh yeah its a usdm ecu. I borrowed a friends ecu which is a weird n336 which neither of us know what it came out of, it worked but still with the same problem so I swapped my n332 back in. It worked on the cards previous jdm motor for what its worth.

fredrx7

Aslo is it infact true that the signal from the ecu for the coil to fire is a varying ground signal?If so can I simply use a small led test light to check for this signal at the ecu connector and then if Im getting it from the ecu try to conform it at the coil connector?
Also correct me if im wrong but the fact that the primary is firing confirms the cas is okay and the wiring to the ecu is ok? Am I correct in this thinking? A friend told me it has 2 pickups so that isnt necessarily the case

satch

iTrader: (1)

Typed coil wires but specifically meant the plug wires.

The voltage readings are to be taken from the ECU (two are output signals and one is an input signal).

Pin 1X is the wire which tells the coil to fire. W/the car running the signal is too rapid to measure for changes in the signal thus it is measured w/the engine being rotated by hand w/key to on. The signal varies between two values with one being 0 volts and the other being 5 volts. As you rotate the main pulley (via the alternator pulley) the signal will stay at one value and then quickly change to the other value before returning to the initial value and this happens repeatedly as the the pulley is rotated.

Also, just because the coil is bolted to the fender does not necessarily mean the ground is good. Sometimes it is required to sand down the two contact/mating points and clean out the bolt thread of grease and dirt to create a good grounding. If pin 1X (trigger signal) tests out then the coil, plug wires or plugs are bad.

RotaryEvolution

iTrader: (30)

is it a USDM engine harness or one that came with the engine?

fredrx7

Ok Ill check it out when I get home and see what I find for values

And it is a usdm harness/car and jdm motor. Also the last motor this car had in it was a jdm motor that ran fine (never idled well but do any rx7's?)

RotaryEvolution

iTrader: (30)

well i would check the coil grounds as satch suggested, seems the most logical. keep in mind fouled trailing plugs will also simulate a failed trailing coil.

fredrx7

This car is killing me! I just realized today that it wont even rev. It stalls out when I try. I know the jdm motor has reversed fuel lines but when I hooked mine up originally it wouldnt start so after looking closer I realized the fpr and dampener are reversed from the manual diagram. So I ran the fuel into the pulse damper at the back of the secondary fuel rail, fuel goes through it then down to the primary rail, towards the back of the car to the fpr then out and back to the tank. Is this all correct? It was the first time the car started after I did that so I thought I was all good, now I dont know if that all is right or not.

fredrx7

I should add that its not starting easy either, its requiring me to crank the starter for like 5 or more seconds to get it to start, and when it does it sounds really weak. I put a new fuel pump in recently too, when I did my dumbass forgot I had drained the tank of fuel and I tested out the wiring to the fuel pump by starting it for a few minutes. Could I have damaged it by running it dry for a few mins? Its a 255lph from HPF I think was the name of the company that made it. I had a lot of fuel leaks at the rail before I fixed them with new clamps and o rings so there's deffinatly pressure in there.

fredrx7

Also I double checked and cleaned them and my grounds are clean and good to go. The secondary coil works as a ground on my multimeter with the positive probe on the battery wire, so that checks out.

satch

iTrader: (1)

When in doubt clean the contact points regardless. Takes but a few moments of effort so as to remove it from the list of possible causes.

fredrx7

Yeah yesterday I pulled the coil out as well as the ground clip beneath it and thoroughly sanded and cleaned them. I am going to get a new multimeter and check output at the ecu and coil hopefully tomorow. Thanks for the continued interest in helping me