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-   -   Not getting spark, tach not moving while cranking (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/not-getting-spark-tach-not-moving-while-cranking-973059/)

Robftw 10-12-11 04:42 PM

Not getting spark, tach not moving while cranking
 
Both coil packs will not fire a spark, the battery is brand new.

I've cleaned all the contacts on both of them and re-installed, same issue.

All of the fuses are good, spark plugs are brand new, wires are kinda old but show no signs of corrosion whatsoever. They read OK with the multimeter

Where else can i look? Also it did have the mazda alarm system.. could that be my problem? I'm not sure which connector to jump to make it fire

satch 10-12-11 05:02 PM

Does the car turn over w/key to start? If it does then the alarm is not the problem.

Pull the White 2 wire plug off of the leading coil and test the Black/Yellow wire for battery voltage w/key to on as it should be present. This wire powers the coils.

There is a Green check connector w/4 wires near the leading coil. One of the 4 wires is Black/White. W/key to on this wire should have battery voltage. This wire powers up the ECU which is vital.

Make sure the Meter fuse is good. If the idiot lights come on w/key to on then this fuse is good.

Robftw 10-12-11 05:18 PM


Originally Posted by satch (Post 10821706)
Does the car turn over w/key to start? If it does then the alarm is not the problem.

Pull the White 2 wire plug off of the leading coil and test the Black/Yellow wire for battery voltage w/key to on as it should be present. This wire powers the coils.

There is a Green check connector w/4 wires near the leading coil. One of the 4 wires is Black/White. W/key to on this wire should have battery voltage. This wire powers up the ECU which is vital.

Yes it turns over with the key, i'll go pull the plug and check for voltage now

Robftw 10-12-11 05:29 PM

Just checked the leading coil, it does not get any power when the key is in the on position

satch 10-12-11 05:39 PM

There is a relay located to the right of the steering column just under the dash. The relay is Black and Yellow. The plug to the relay has two rows a top row and a bottom row. The top row has three wires. The center wire is Black/White. This wire should have voltage w/key to on. If it doesn't then it llikely means the 15 amp Engine fuse is blown which would prevent the Main relay from working which would prevent the Black/Yellow wire at the leading coil from having voltage in addition to the B/W wire at the Green check connector near the leading coil.

RotaryEvolution 10-12-11 05:42 PM

check the EGI fuse first.. then may as well pop out the computer fuse inside the cabin. takes less time to pop 2 fuses out and inspect them.

Robftw 10-12-11 05:43 PM


Originally Posted by satch (Post 10821753)
There is a relay located to the right of the steering column just under the dash. The relay is Black and Yellow. The plug to the relay has two rows a top row and a bottom row. The top row has three wires. The center wire is Black/White. This wire should have voltage w/key to on. If it doesn't then it llikely means the 15 amp Engine fuse is blown which would prevent the Main relay from working which would prevent the Black/Yellow wire at the leading coil from having voltage in addition to the B/W wire at the Green check connector near the leading coil.

I'll go check that, brb

Robftw 10-12-11 06:05 PM

It was the fuse, i completely forgot about that one in the fusebox inside the car. I was able to get it started, however it will only run on ether =/ i think my fuel lines may be clogged

Robftw 10-12-11 06:09 PM

Also, it has 5 gallons of fresh gas in the tank, the fuel meter did not move for the 20 seconds it was running, i'm assuming a fault in the fuel system, i cannot hear the pump running

satch 10-12-11 06:13 PM

Jumper the fuel check connector and listen to see if the pump turns on w/key to on.

And what is the "fuel meter." Does it measure fuel pressure or what?

Robftw 10-12-11 06:15 PM

Oh i wrote that wrong, its the fuel gauge in the dash.

i'm gonna go jump the connector now

satch 10-12-11 06:22 PM


Originally Posted by Robftw (Post 10821804)
Oh i wrote that wrong, its the fuel gauge in the dash.

i'm gonna go jump the connector now

The Meter fuse powers the gauges. If the tach bumped or worked when trying to start the car then this fuse is good.

Robftw 10-12-11 06:29 PM

I jumped the wire, turned the key to ON and waited 10 seconds, heard no noise. I repeated this step 3 times and still nothing.

The car started by itself but for about 2 seconds and shut off, won't start again without ether

satch 10-12-11 06:42 PM

The relay you looked at near the steering wheel governs the voltage to the fuel pump.

Top row far left B/W wire should have voltage w/key to "start." Does yours?

You know the top row center B/W wire should have voltage w/key to on. Does it still?

The Blue wire at the top right should have voltage w/key to start and no jumper in place. With the fuel check connector in place it should also have voltage w/key to on.

The "solid Black" wire in the bottom row far left is a ground wire. You could use this wire for the voltage meter when looking for a ground source when testing for voltage in that area of the car. Black meter lead to this Black wire and the Red lead to the wire being tested for voltage.

Lastly, if the Black wire is jumpered to the Brown wire in this plug it is the same thing as jumpering the fuel check connector but in a different place.

Robftw 10-12-11 06:49 PM


Originally Posted by satch (Post 10821833)
The relay you looked at near the steering wheel governs the voltage to the fuel pump.

Top row far left B/W wire should have voltage w/key to "start." Does yours?

You know the top row center B/W wire should have voltage w/key to on. Does it still?

The Blue wire at the top right should have voltage w/key to start and no jumper in place. With the fuel check connector in place it should also have voltage w/key to on.

The "solid Black" wire in the bottom row far left is a ground wire. You could use this wire for the voltage meter when looking for a ground source when testing for voltage in that area of the car. Black meter lead to this Black wire and the Red lead to the wire being tested for voltage.

Lastly, if the Black wire is jumpered to the Brown wire in this plug it is the same thing as jumpering the fuel check connector but in a different place.

My multi meter just died on me, i won't be able to check these things for a few hours until it charges.

Is there any other places to check in the mean time? engine bay fuses are good, so are the ones inside the car..

I'm going to check for loose connections

RotaryEvolution 10-12-11 06:58 PM

pop off the rear carpet and the LR shack tower cover, remove the metal cover from the cover of the fuel tank and inspect the wiring from the tank all the way up to where it meets the main interior harness at the LR shock tower.

considering you have no gas gauge i suspect you have an issue with the pump connector unplugged or a rust rotted tank.

Robftw 10-13-11 06:34 AM

I'm trying to check the harness now, which wires going to the fuel pump are supposed to have power when the key is on and the yellow switch jumpered

Robftw 10-13-11 07:29 AM

Well...

I took the pump out of the car, it was covered in fuel-gel the entire pump is clogged with it lol..

Off to the auto parts store i go !

satch 10-13-11 08:50 AM


Originally Posted by Robftw (Post 10822394)
I'm trying to check the harness now, which wires going to the fuel pump are supposed to have power when the key is on and the yellow switch jumpered

The Blue wire from the Rear harness side that plugs into the fuel pump pigtail would be the wire to check if need be.

RotaryEvolution 10-13-11 11:52 AM

it's black/white from the strut tower to the top of the fuel tank, then it turns blue once inside the tank. should have between 9.5 and 11.5 volts with the key on.

Robftw 10-13-11 12:50 PM

I replaced the pump and re-wired it, everything runs fine

Once and a while the car studders badly while accelerating or revving. I'm going to assume it just needs a new fuel filter and an injector cleaning

RotaryEvolution 10-13-11 01:21 PM

that's good.

and for clarification the voltage is present at that wire with the fuel pump test connector jumpered or the car cranked for a second to trip the airflow meter, for anyone else diagnosing a similar problem.

Robftw 10-13-11 01:27 PM


Originally Posted by Karack (Post 10822773)
that's good.

and for clarification the voltage is present at that wire with the fuel pump test connector jumpered or the car cranked for a second to trip the airflow meter, for anyone else diagnosing a similar problem.

It starts by itself with no jumpers, it trips from the afm meter

Also offhand, do you know how long the brake lines are for the rx7 going from the front of the car to the rear?

RotaryEvolution 10-13-11 01:51 PM


Originally Posted by Robftw (Post 10822786)
It starts by itself with no jumpers, it trips from the afm meter

Also offhand, do you know how long the brake lines are for the rx7 going from the front of the car to the rear?

no idea, they basically run the length from the master cylinder to the driver's side of the differential so about 12'.

Robftw 10-13-11 06:36 PM

I bought all new brake lines and the tools to cut and bend them..

Now i need to figure out why my car studders, im thinking its the filter but im not sure


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