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-   -   not gettin any spark or fuel. need help!! (https://www.rx7club.com/general-rotary-tech-support-11/not-gettin-any-spark-fuel-need-help-749466/)

bansheemx 04-18-08 08:22 PM

not gettin any spark or fuel. need help!!
 
recently bought a 90 gtu, fuel pump was bad so i replaced it with a new one but it will not kick on with key. also the car is not getting any fire. i dont kno much about rotarys, any suggestions? :wallbash:

polito Racing 04-18-08 08:41 PM

check the EGI/ INJ fuse on your engine bay if good check your CPU.

bansheemx 04-24-08 11:53 AM

s5 no spark
 
thanks. the fuse is good. is there any way to check the cpu?

MazdaMike02 04-24-08 01:55 PM

It has nothing to do with rotaries. Its ignition, fuel circuits with fuses and relays. Same stuff in every modern car dude.

Check your main fuse, its the blue 100amp fuse in the middle of the others on the fuse block.

Don't bother checking the ECU, RX7 ECUs are bulletproof..Mine was submerged in water and caked with mud, a good cleaning and it still works. As long as theres no corrosion on the circuit boards they will still function properly. Actually, s5 ECUs are the only ones I know of that fail cause of OMP problems which fry the ECU.

Follow troubleshooting procedures in the online factory service manual, or if you you own the book use it. Haynes manuals also have steps for troubleshooting.

Fuel:
1. Check EGI main relay (located on the drivers side fender, to the right of the trailing coils...its a gold box with 2 connectors coming out of it.)
Verify its operation, and the voltages. Remember, relays can still be bad even with proper voltage.
2.Check fuel pump connector behind driver side rear strut tower. Check voltages, refer to manual. If voltages are correct, your fuel pump has failed.

After you fix the fuel pump issue, theres a yellow 2 prong connector near the intake, just above the AFM. Jump the 2 prongs to run the fuel pump without the ECU. You'll hear it.

Spark:
1. Check EGI main relay (Don't bother if you've got fuel and you already checked it)
2. Check plug wires, make sure they're in the right spots. L1 on L1, T1 on T1, etc etc. Theres a plastic cover on each coil that says which is which. On the motor the top 2 are trailing 1 and trailing 2, bottom are leading 1 and leading 2. Number 1 rotor is the front rotor closest to rad.
3. Verify ignition timing: Theres 2 marks on the pulley, the one to the right is leading and the one to the left is trailing. Line up the needle on the front cover with the right mark. Pull out your CAS, drop it in having the 2 tooth gear parallel with the engine, have it lining up with the first sensor in the CAS. That should put you in the ballpark of normal timing, you'll need a timing light to get it to OEM.
4. Check coil resistance, pop of the plastic cover and you see 2 screws with wires under them. Check the resistance across them, and refer to the manual. If I remember correctly, under 1 ohm is in spec.
4. Check coil power, pop off the white 2 prong connector you'll see 2 wires come off of it going into the coil. Check if you have power.
No power means a blown engine fuse.

If all that checks out and you still have no spark, pull off the intake, throttle body, dynamic chamber and extension manifold. To the right of the EGR valve is an ECU ground, this needs to be bolted to the rotor housing or the ECU will not let the car spark.

If all that checks out, then check the ECU. Its very rare that they fail, like I said mine is bulletproof. I could take a leak on it, let it dry and it would still work.

polito Racing 04-24-08 01:56 PM

i meant to say ECU. the easiest way is to find someone elses and swap it arround to se if this changes anything. are you hearing any clicks when you move the key to on?


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