Fuel Injection

[kolkim]

Hello, this is my first post so i hope I'm doing this right. I have a question about the installation of a fuel injection kit. I have installed a mopar multi port fuel injection kit on my 1984 Scrambler w/ AMC 258 i6 / 4.2l I6 and cannot get fire to my spark plugs. I have been on the phone with the guys at HESCO, who I guess make these kits for mopar, several times. In my numerous conversations with them, we have concluded that I have installed the kit correctly. All the wires are connected to the right ports, I have 12 volts everywhere I need it, I have a good ground, I have run new high pressure fuel lines correctly and am getting fuel to the rail, my engine is at TDC and the distributor is inserted correctly, I have tested the coil and it is functional, the sensor that reads the notches in the harmonic balancer is correctly spaced away from the harmonic balancer. I'm at a loss here. I spent nearly $3,000 on the kit and really don't want to have to take it to a mechanic and have to spend a bunch more money on something that should have worked in the first place. Could I possibly have received a faulty distributor? Not sure how to test a distributor. All I know is, I've got power to the coil and power to the distributor but nothing coming out of the plug wires. Any thoughts would be very much appreciated.

 

[Torxhead]

There is the crank sensor and the cam sensor that might need checking as a thought.

 

[Dan77CJ7]

Most good shops have all the tools needed to test and set up the multi ports. Thats why Gomer And I went with the carb. cuz we dum....and poor...ugly too.

 

[gold jeep]

I put one on my 82 CJ7 and it works grate

 

[kolkim]

Okay, thanks! I'll look into that.

 

[hole]

After double checking those sensors, I'd go back to that distributor. You said power in but no power(spark) out. That makes me question everything about it, right cap, right rotor, possibly internally damaged. What are the guys at Hesco steering you towards? My past dealings with them they have been pretty spot on with their advice, good bunch of guys there.

 

[ThisGuyUKnow]

Hello, this is my first post so i hope I'm doing this right. I have a question about the installation of a fuel injection kit. I have installed a mopar multi port fuel injection kit on my 1984 Scrambler w/ AMC 258 i6 / 4.2l I6 and cannot get fire to my spark plugs. I have been on the phone with the guys at HESCO, who I guess make these kits for mopar, several times. In my numerous conversations with them, we have concluded that I have installed the kit correctly. All the wires are connected to the right ports, I have 12 volts everywhere I need it, I have a good ground, I have run new high pressure fuel lines correctly and am getting fuel to the rail, my engine is at TDC and the distributor is inserted correctly, I have tested the coil and it is functional, the sensor that reads the notches in the harmonic balancer is correctly spaced away from the harmonic balancer. I'm at a loss here. I spent nearly $3,000 on the kit and really don't want to have to take it to a mechanic and have to spend a bunch more money on something that should have worked in the first place. Could I possibly have received a faulty distributor? Not sure how to test a distributor. All I know is, I've got power to the coil and power to the distributor but nothing coming out of the plug wires. Any thoughts would be very much appreciated.

I make 4.0 conversion harness and from trouble shooting them in the install procces and from what you are describing, I am pretty sure the problem is your CPS.

Coil will not fire if the Computer is not getting a reading from the CPS. Since you bought a complete kit this may not be the case, but the last customer I had that used the HESCO CPS relocation kit had to actually install the wire plug onto the CPS wiring. When he did that he accidentally put the wires in the wrong place and experienced a no spark situation. If you had to add the plug your self, I'd double check the wiring because sounds like you are having the exact same issue.

 

[ThisGuyUKnow]

After double checking those sensors, I'd go back to that distributor. You said power in but no power(spark) out. That makes me question everything about it, right cap, right rotor, possibly internally damaged. What are the guys at Hesco steering you towards? My past dealings with them they have been pretty spot on with their advice, good bunch of guys there.

The Coil will receive 12v with the key on but the ground side of the coil runs through the computer, if the computer does not sense the CPS, it will not ground the coil.

 

[kolkim]

Okay, thanks guys! I will try re-positioning the wires in the connector on the CPS. In my conversations with the HESCO guys (I agree, they are very helpful and friendly. Good guys!) we discovered that the wires in the connector coming off the harness, and going to the cam shaft position sensor inside the distributor were not in the correct position. Bennie at HESCO sent me color photos of how the wires were supposed to be positioned in the connector and i fixed them. Maybe the wires in the connector for the CPS were positioned incorrectly too.

 

[Sasquach]

Nothing of value here but will add mine started right up but it did run so rough at first I thought I had something backwards, after the computer settled everything down it just purrs.
I would go thru the instructions again verifying all is correct but sounds like you may be past that.

 

[kolkim]

Okay, so I had a little time yesterday after work to mess with the jeep. I found a picture on another jeep forum that showed the voltages that were supposed to be coming from each of the wires in the CPS connector (picture is attached as thumbnail, hopefully I did it right). According to the picture, the wire on the left(A) should show 5v, the middle wire(B) is the ground, and the wire on the right(C) should show 8v when looking at the connector with the clip on the top. According to the picture, the wires in the connector on my harness were positioned correctly from the manufacturer. So i guess the wires' position is not my issue. However, when I tested the voltages on the three wires I discovered that my right wire did show 8v and the middle wire is the ground wire, but the left wire only showed a little over 2v. Then i decided to test the wires in the connector for the cam shaft position sensor in the distributor and they showed the same voltages. 8v on the right, none in the middle, and just over 2v on the left. So, it looks like to me I'm not getting enough voltage from my wires on the left. Only about 2v rather than 5v. My question is, how is this happening? My battery is fully charged and produces ample voltage at all times. Is there some reason that the voltage in my left wires is being reduced? I'm no electrician so I'm kind of at a loss here. Any help would be greatly appreciated.