Donor Motor 5.2 out of a Dodge 1500 p/u

Installed into a street rod utilizing a Telorvek wiring panel to keep the F.I. on it. We've been over the ground strapping and a complete check of each individual wiring to verify all wires/components are connected to the proper circuits and voltages which they do. Also, 50 P.S.I. at fuel rails confirmed.

Power to all +5v sensors (Cam/CKS) is showing 6.3v EDIT: @5v . +12 at coil.

Everything shows power but no spark/start.

Read on this forum about security issues (SKIM/VSS), is it possible that this is the case?

When tested with OBDII it showed P0443 was the only code, it was erased. now (1st) computer will now not show a connection to the OBDII. Dead?

Replaced with (2nd) computer, when connected the OBDII showed the same code as before.

Also, the fuel pump (new unit) originally worked properly (2 second on/off) now it does not shut off after 2 seconds. It runs until the key is turned off. All wires to the unit check out.

Any help would be greatly appreciated as trying to best not chase the tail on this thing.


-Patrick

 

Welcome to DF.

First, before anything else, please read this.

I will move this to the main section where all the tech questions go, get you some help.

 

There's deffinitely an issue with having 6.3V on your 5v feed. That tells me that something is wrong right there. Wires crossed,or something.Bad grounds.

As far as the computer is concerned,all the values would be skewed from the sensor readings. High and Low voltage, generally will mean a no-start condition, or very poor running.

Disconnect everything on the 5v circuit and meter the voltage again, if 5v is verified, start plugging in one sensor at a time and remeter every time until the voltage changes. If the voltage drops it will be a bad sensor, if it spikes,and it shouldn't,the wiring on that circuit is probably incorrect.

As far as the continuious run on the fuel pump,that signal comes from the computer as a ground. Two computers with the same symptoms,says there's something in the wiring. That's my thoughts.

 

As a member of a few other forums I appologize for missing the proper sub-category! Thank you for the proper re-direct.



Neilcustoms.....sounds like the right direction to head now, thank you for that!

Will get back on this after going over voltages and wiring again.

-Patrick

 

Disconnected it read +5.10 on the circuit that the CKS, tps, and a two other sensors are on.
When reconnected, it bumped to +5.40. CPS was same. +5.10

 

That should be close enough.

Are you getting spark? Injector Pulse?

 

Everything reads right, just no spark.

 

Check the crank sensor. Make sure it wasn't damaged....... If there are metal shavings on it..... you might be able to just clean it off, but, replacement is prolly gonna be in your future.

If you have an aftermarket sensor.... these truck are notorious for not liking them.... and refusing to run.

What year truck was the donor for the PCM, and wiring harness?

 

It was a complete setup motor and PCM from a 1998 1500 5.2l

Crank sensor is possible, any chance you know the Ohms test readings for it?

 

Haven't the faintest.

If it was on the motor when you installed it, good chance it was damaged. (a common fate for them in such circumstances..... same if the trans was installed with it in place.)

Do you get injector pulse?