Yet another no start. Renix 6 cyl

[MancheKid86]

Things I have swapped

Cps

Fuel pumps+sending units

Fuel pump resistor

Spark plug wires

Coil

Ignition control unit

 

Facts

Tested good cps installed

,fuel delivery+fuel pressure good

12v to the ICU

No power on coil tower output - new coil installed + 2 other know. Good coils

 

 

Is there a way to test the cps harness to the ecu?

Or what else can I try?

[88whitemanche]

Checked your grounds??

[big66440]

Are you getting a good spark at the spark plugs? do you have compression? as far as testing the CPS signal to the ECM you will need a wiring diagram and back probe the " return" A/C signal from the CPS to the ECM at the ECM connection. Then you can see if you have a 4.5 to 5 volt reference to the CPS at the CPS connection ( sorry I don't have the wire color/locations for this) IIRC there was a campaign/recall that bypassed the fuel injection harness and connected the CPS directly to the ECM for a cleaner signal, I did this on my Comanche and it was very quick and easy,if you plan on doing this make sure you use a grommet to run the wires through the firewall and a good water proof connection.

[MancheKid86]

No spark,

New icm and coil and wires plugs are good perfect color and no fouling

12v dc to icm

 

Tested cps,

.5 acv output and 190 ohms resistance

Pulled ecu tested cps input and had .5 acv to ecu

 

What else will create a no spark?

[MancheKid86]

Adjusted the icm contacts and gained spark,

Would fire up on wd40 and continue running afterwards

Ecu checked out

 

Vice grips on fuel return line and she fired right up

Upgrading to 49 psi FPR as a fix