help with s5 turbo running on one rotor
#1
help with s5 turbo running on one rotor
I just picked up a s5 vert with a s5 swapped turbo motor that is running very poorly, the setup is completely stock with the exception of a racing beat downpipe and exhaust. Here's what I know so far.
Any help would be greatly appreciated. What else am I missing that I need to check which would wipe out a rotor?
- #2 rotor is dead with major lack of power and idles at 200rpm
- #1 spark plug is dry #2 spark plug is wet
- rotary compssion test has ruled both rotors have strong compression
- verified spark on both rotors
- swapped primary and secondary injectors with no change
- no smoke coming out of tailpipe
- disconnecting CAS and spinning gear I can hear the primary injectors click which i assume rules out a ecu or wiring issue to injectors
Any help would be greatly appreciated. What else am I missing that I need to check which would wipe out a rotor?
#4
It's all stock. The ecu unfortunately I can't see the number as its been scratched off, the friend I picked this car up from had the car working fine, drove the car for 6 months before this happened and his story was from one day to another car started and it had a very low idle and major lack of power
#6
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If you have a problem w/the rear rotor then focus on the rear plugs which there would be two of them, but you refer to #2 plug being wet. Is this the rear leading or the rear trailing or both? This is what is trying to be ascertained.
And is this a JDM swap or USDM?
And is this a JDM swap or USDM?
Last edited by satch; 09-18-14 at 10:26 AM.
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#11
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I agree.
Try putting new plugs for the rear rotor, if you haven't already. Check plug wires for arcing with the hood open in a dark space (safety - stay away from moving or hot parts, in a ventilated space or do it real fast cuz of CO poisoning).
I know you said you checked for spark, but make sure the spark is strong on each plug. Focus on the rears.
Try putting new plugs for the rear rotor, if you haven't already. Check plug wires for arcing with the hood open in a dark space (safety - stay away from moving or hot parts, in a ventilated space or do it real fast cuz of CO poisoning).
I know you said you checked for spark, but make sure the spark is strong on each plug. Focus on the rears.
#13
Tonight I hooked up a spark tester to each spark plug and took a short video of each, I was not able to see any issues with visually looking at spark perhaps any of you may see a issue with how the spark looks in the video.
Rotor #1 Trailing spark
Rotor #1 Leading Spark
Rotor #2 Trailing Spark
Rotor #2 Leading Spark
Do I have anything that sticks out? If spark appears to be normal, are there any other areas or parts I should test?
Thanks
Rotor #1 Trailing spark
Rotor #1 Leading Spark
Rotor #2 Trailing Spark
Rotor #2 Leading Spark
Do I have anything that sticks out? If spark appears to be normal, are there any other areas or parts I should test?
Thanks
#14
Spent a little more time on the car tonight and tested fuel pressure: Idle 32 psi and while holding the idle at 1500 rpm pressure drops to 30psi and holds til I let off the gas. I removed the cat as well just to confirm is was not clogged and still same issue.
#17
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Blue is the weakest. You should ohm out the plug wires. You should also reground the coils to the fender by sanding down the contact points between the two as well as cleaning the thread mounts of dirt and grease. Some reverse the bolt where the head is in the fender well which helps prevent dirt and grease from finding its way into the threads. If that doesn't work then you might want to replace the coil/igniters. And make sure you have the correct plugs.
#18
Sounds good I'll do all these steps and report back, thanks again for the help
Blue is the weakest. You should ohm out the plug wires. You should also reground the coils to the fender by sanding down the contact points between the two as well as cleaning the thread mounts of dirt and grease. Some reverse the bolt where the head is in the fender well which helps prevent dirt and grease from finding its way into the threads. If that doesn't work then you might want to replace the coil/igniters. And make sure you have the correct plugs.
#19
Update: cleaned off the grounds and connectors for both trailing and leading coils, no difference, also I checked side by side with my good working s4 turbo car and the spark colors and pattern look identical, I could just be getting my colors mixed up. I think we have suitable spark but please feel free to comment.
#23
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second new wires are around 7k ohms, and 16k is the upper limit. the FC manual doesn't specify, but the 1st gen books do.
#25
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If you're getting spark then you should focus on fuel. Pin 3Y (Light Green wire) is the rear primary injector and pin 3Z (Light Green wire) is the rear secondary injector. W/key to on they should both have 12 volts. W/key to start they should have close to 8 volts or so. You might also want to unplug the boost sensor and see if this makes a difference in the rear rotor working or not. You can also unplug the TPS to see if it helps any. Both these sensors will cause fuel cut to the rear rotor under certain situations and perhaps one is playing a role in your problem. And have you checked for error codes? If the warning light cluster does not have the CEL light then it means it is a JDM.
If an LED light were connected to pin 3Z and pin 1B then w/key to start the light should flicker repeatedly indicating the ECU is triggering the injector properly. Same thing can be done for the other rear injector. And you should place the injectors back to their normal position if you have not already done so.
If an LED light were connected to pin 3Z and pin 1B then w/key to start the light should flicker repeatedly indicating the ECU is triggering the injector properly. Same thing can be done for the other rear injector. And you should place the injectors back to their normal position if you have not already done so.
Last edited by satch; 09-30-14 at 03:02 PM.