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Re: 4.0 head and EFI on a 4.2 block

Posted: September 24th, 2011, 10:27 pm
by Jeep-Power
to test the crank sensor: use a ohm meter set to the 1K - 10K scale. Test for resistance between the sensor ground ( bkl/lt blu Pin #4) & the signal (Pin #44-- Tan/Yellow). There should be open-- NO resistance. Replace if any resistance is noted.

The cam sensor: you need a analog (with a needle) voltmeter set to the 15V DC scale.

Leave sensor hooked up/plugged into harness.

Connect the (+) lead to the sensor output wire (tan/yelow - pin out #24) & the (-) lead to the sensor ground (black/blue Pin# 4).

Remove the dist. cap & rotate the engine until the rotor is at the 11 o'clock position. The moveable pulse ring should be within the sensor pickup.

Turn on the ignition. The volt meter should read approx 5V. If not, check for voltage on the supply wire (orange - Pin # 7)

a double check is to crank the engine & watch the needle fluctuate. If it does not-- replace the cam position sensor ([NAPA]pn: 56027023)

Gotta love owning a FSM (1995 XJ & YJ) 8-)

I hope this helps!

Re: 4.0 head and EFI on a 4.2 block

Posted: September 25th, 2011, 6:35 am
by herbiehind
greatlakes 4x4 . free pdf's lots of fsm's and safe .

Re: 4.0 head and EFI on a 4.2 block

Posted: September 25th, 2011, 9:19 am
by rayzr
Could you please post up a direct link for the FSM?

Thanks,
Ray

Re: 4.0 head and EFI on a 4.2 block

Posted: September 26th, 2011, 2:28 pm
by rayzr
Ok, It still won't start. So this is what I have.
1. New Hesco dampner and sensor on front of engine. I tested the sensor with a VOM and it is open between pins 2&3.
2. New cam sensor in dizzy.
3. New cap, rotor, wires, and plugs.
4. I metered out the coil, and all values are within specs in the FSM.

This is how I have it wired.
Red wire from pos 3 in PCM is wired always hot from cab of Scout.
Lt Bl/red is wired to keyed hot.
I have the Blk/Tan wire grounded to the block under the coil with the alt.

The relays are engaging when the key is moved to start/run.
There is fuel pressure at the rail.

I am using the starting circuit from Scout for simplicity. No need to rewire through PDC?

All of the sensors are connected, with the exception of the O2. This will be installed after I get the truck running and take to a friends to weld in the bung.

The truck cranks, but there is no fire at the dizzy.

Please help me get this beast fired up! :huh:

Thanks,
Ray

Re: 4.0 head and EFI on a 4.2 block

Posted: September 26th, 2011, 3:06 pm
by herbiehind
rayzr wrote:Could you please post up a direct link for the FSM?

Thanks,
Ray
http://www.greatlakesxj.com/index.htm
go to bottom of page and pick the pdf you want .

Re: 4.0 head and EFI on a 4.2 block

Posted: September 26th, 2011, 3:46 pm
by rayzr
I did not see any 1995 ZJ FSM on the site.

Re: 4.0 head and EFI on a 4.2 block

Posted: September 27th, 2011, 9:55 am
by herbiehind
wouldnt an xj with a 95 4.0l be of help?

Re: 4.0 head and EFI on a 4.2 block

Posted: September 27th, 2011, 10:28 am
by Jeep-Power
herbiehind wrote:wouldnt an xj with a 95 4.0l be of help?
As far as I know, they share the identical schematics & PCM. I can't see why not.

The truck cranks, but there is no fire at the dizzy.

Please help me get this beast fired up! :huh:
rayzr--

Getting ti to crank is the easy part.

do you have power to the coil? Injectors? Are they firing?

When you say the relays are clicking-- is that the ASD? Verify that it is working & that it has power going to it & then out of it?

Re: 4.0 head and EFI on a 4.2 block

Posted: September 27th, 2011, 10:32 am
by rayzr
Could you walk me through what to check?
I'm just scratching my head right now......

Thanks

Re: 4.0 head and EFI on a 4.2 block

Posted: September 27th, 2011, 11:03 am
by rayzr
When I turn the key to the run position the ASD relay does activate, as does the fuel pump. It shuts down after a second or so.
I am getting voltage at the injector on the Dk green/Orange when the key is in the run position. Is this what I am supposed to see?
How do I check to see if is putting out the correct output??

Ray

Re: 4.0 head and EFI on a 4.2 block

Posted: September 27th, 2011, 2:17 pm
by rayzr
And, I do have 12v at the coil with the key on.

I'm starting to lean towards a bad CPS from Hesco..........

Thoughts?

Ray

Re: 4.0 head and EFI on a 4.2 block

Posted: September 27th, 2011, 3:28 pm
by Jeep-Power
huh.

The injectors should have 12V.

The crank & cam sensors will have about 5V at them.

Re: 4.0 head and EFI on a 4.2 block

Posted: September 27th, 2011, 3:46 pm
by rayzr
Check, The injectors are at 12V.
I do have 12V at the coil too.
The cam sensor was replaced with new last night.
What sould the voltage be, and when, at the cam sensor? Is there to be voltage at the CPS? What and when should I see?

Thanks,
Ray

Re: 4.0 head and EFI on a 4.2 block

Posted: September 30th, 2011, 2:49 am
by rayzr
Sorry about the long time getting back to this. we had LOTS of heavy rain on Wen and I had to have a tooth pulled yesterday! I think I am going to hit it hard today and see if I can get this up and running.
What do I need to do to test out the ASD curcuit? I know I have voltage to the coil and injectors. The cam sensor is new. I think it might have to do with the Hesco crank sensor. The sensor is as close to the balancer as it will get, without hitting it. Is there a voltage test I can do to verify the CPS?

Thanks,
Ray

Re: 4.0 head and EFI on a 4.2 block

Posted: September 30th, 2011, 7:09 am
by Jeep-Power
rayzr wrote: The sensor is as close to the balancer as it will get, without hitting it.
woah-- that might be your issue. There needs to be atleast .030" gap between the sensor & the wheel. I'm pretty sure it will work with as much as a 1/8" gap. One thing I'm certain of is that if it is too close (almost touching) it will NOT work. I'd set it to .060 & see what happens.