1990 YJ coil, voltage, ICU, something ISSUES

So my thought on vapor locking has turned into electrical problems these are the things i was told after finally breaking down and taking it to a shop.
I took it in for what i thought was a carb issue, i have replaced my stock carter with a Weber. I was getting what i thought was vapor lock symptoms, the mechanic quickly diagnosed it as most likely electrical. If the jeep was hot it would only send spark on the let off of the key turn, if it was cold the issue was non existent.
1st thought was ignition module ,but after switching out with a good one that didn't fix the issue moved on to the alternator. Checked voltage to the battery and found 18 volts going to the battery, and 13 volts at the coil. I am using a Accel super coil and at install i had had to switch the +/- connections to make the jeep run properly, after switching the +/- connections at the coil the not starting when hot has been fixed and the voltage to the battery and coil are with in normal limits.
BUT...... the jeep is not running QUITE right and now my voltage meter does not work. This is a jeep and it's ALWAYS a work in progress. I have ordered a new alternator, full distributor, ignition control module , starter relay, plug wires, and ignition switch. I have gotten very tired of wrestling with this problem and figure I'll wipe out all the possible factors and go from there.
Hopefully this will give Enough info to fire someone's synapses and hit a solution

 

Have you already installed the above mentioned parts and you are still having these problems, or are you waiting on them to be shipped.

Full out I dump all Ford electronics and replace with Chevy. Get rid of the ignition module, coil, and distributor, bypass the computer (called the Nutter bypass), install a 1 wire HEI distributor with integrated coil pack, and you will never have an electronic problem again. My 2 cents, but and IF

you are like so many Jeep enthusiast and insist on running the Ford products (that I suggested earlier to eliminate) to keep it original; you do what you are doing now. Replace them one at a time, in order of expense. In the end it is usually the distributor or the coil or both. Last thing to replace is the computer. Don't forget plugs and wires too. Also These old jeeps DO NOT like specialty plugs, i.e. bosch, splitfire, platinum, etc. They only run well on old style basic Copper cored and preferable Copper tipped plugs for example:

Autolite Copper Core - Spark Plug
Line: ATO | Part # 985


$1.99 Each

Quantity

Champion Copper Plus - Spark Plug
Line: CHP | Part # 82


$2.49 Each

Quantity

ACDelco - Spark Plug
Line: AC | Part # 41-631


$2.49 Each

Quantity


I like the Autolites the best.

 

Thanks for the input, no i have NOT installed the new parts yet but likely will do so this weekend as they are arriving today. Im not really a PURist , im a ,JUST F*#@ing RUNist , hahaha. I learned the spark plug thing from experience unfortunately, wasted $$ on SUPER plugs but now im back to good ol champion copper.
I tried the nutter bypass when i replaced my carb and the jeep would NOT start. AT ALL. I have looked at the MSD HEI distributor but truthfully didn't realize it replaced all the other parts too, it was always kind of cost prohibitive for a DISTRIBUTOR. Had I known I could dump all the other stuff I would have looked at it more closely, and now you have me considering trying to send back all these parts and ordering that. Do you possibly have a link to a good install of an HEI distributor? It seems like there would be a lot of splice this wire ,splice that wire in order to have a 1 wire ignition system.
Thanks again for the brain fodder , and I will be doing some reasearch before opening the boxes from Quadratec.

 

I cut the power going to the ignition module which is a switched hot and rerouted it to the HEI distributor. The HEI distributor grounds to the block. The HEI distributor has a second plug which is for your tach. At this point you should have effectively cut everything else out of the loop. I have a 79 without the computer, but the theory should be the same. I'll try to take some pictures this weekend and amend this post. I also installed a Howell TBI system. It is a wonderful improvement, but since the install I have found another company (Fitech) that is cheaper and I think a simpler install and probably a better setup. I'll use them on my next build, but I don't know if they are California legal like the Howell system is.

 

This is the one I purchased. The girl helped sell it. The price was right too.


ORDER TOTAL
US $90.00
+ US $10.00
shipping
Order Jeep Distributor HEI CJ5 CJ7 YJ 1972-1990 amc 258 232 6 cylinder cyl inline
1 item sold by precisiondistributors
Jeep Distributor HEI CJ5 CJ7 YJ 1972-1990 amc 258 232 6 cylinder cyl inline


Jeep Distributor HEI CJ5 CJ7 YJ 1972-1990 amc 258 232 6 cylinder cyl inline
( 221925737352 )



ITEM PRICE:
US $90.00

 

So i did some reading and it sounds like this is the way to go..... how has no one ever suggested this in the past amazes me. I will be doing a couple returns to Quadratec and a couple to autozone and saving myself a fair amount of $ , that i can use to order my OBA components for my AC compressor conversion. Thanks OFFGRID ,,,,i like the advertising agent for the distributor you bought ,but i think im going with this one , http://www.ebay.com/itm/AMC-JEEP-23...8fde349&pid=100005&rk=3&rkt=6&sd=200804032196
I dont like red hahaha and this one seems to have a good quality rating.

I will update this thread with some pix etc when its all complete

 

Dang that's pretty cheap. Bet it is made in the same plant. I found that the Jeep boots on the plug wires would not fit (too big) the new cap, so I ordered a set of plug wires that fit a mid-70s Nova with the I6. I think it is a 232.

 

Actually just thought of something else, you probably dont have the same starter relay that I have , a small rectangular ,bolted to the fire wall, with 4 wires going to it, battery to relay ,relay to starter and 2 others that run....somewhere. I assume i dont mess with this , but if all the other stuff comes out maybe this does as well?

 

I think you still need the starter relay. I have a starter solenoid pictured . It is what switches the power on to the starter when you crank I believe. If it doesn't work you should probably be able to switch over to the older starter solenoid. I believe your relay probably integrates with the computer which you are now bypassing.

 

You will probably need to order one of these as well:

harness plug SBC BBC 350 454 ignition tach

1 item sold by keyautomotive
HEI GM electronic distributor pigtail harness plug SBC BBC 350 454 ignition tach


HEI GM electronic distributor pigtail harness plug SBC BBC 350 454 ignition tach
( 171831978116 )



ITEM PRICE:
US $13.00

 

Yah that's the old school bugger i used to have to jump on my Subaru cause some one had destroyed the ignition switch . Well ill be emailing the Distributor company for install info if i need it, this is supposed to be a plug and play for the AMC 258 so we will see. And im fairly certain i dont have a ballast resistor on mine, which they make note must be removed. My only other concern at that point is the distributor gear on the cam. I REALLY dont want to be messing around with replacing that.

 

Mine came specific to the Jeep. Didn't have to change the gear. Hopefully yours is too. You don't necessarily need the plug. You can use speaker terminals to plug in, but they have no ancors/latches.

 

Hey OFF, just noticed you suggested the NUTTER |BYPASS, but if Im removing the entire ICM then what would I be bypassing ? All that system is gone. I removed all the random plugs and harnesses that were hanging around after i changed put my old carter carb. I got a bit over zealous and cut my Tach wire , but luckily caught it and reran it. Should have my new HEI installed in the next couple days and as soon as I get my plug wires I should know if its going to start or not.

 

I believe you are correct, I've not done the HEI conversion on a Jeep that has a computer.

 

Guys bought all your recommended parts as I too replaced the Carter with a Webber but didn't remove anything but the EGR stuff. Have the nutter by pass but wanted to do the whole ECM removal. Will be doing the install in the coming days and will post problems/results when possible. Doing this on an 89 Wrangler sport 258 I6, also installing a header. Just finished a 428 super cobra jet install in my buds Shelby Cobra kit car so I hope the wiring is as old school easy as that was! lol Thanks for the input gentleman look forward to exchanging trials and tribulations in the future.

 

Ok, so I've got everything back together ,with new wires where applicable , but all i get is the dreaded CLICK,,,,, kinda like a dead battery CLICK but if i jump the solenoid it will turn over. Not sure about other stuff yet, cant check spark while trying to jump the solenoid, doing this solo.
I have checked voltage at my ignition relay,,,which i replaced as well,,,I get 12+ with key on at the yellow(switched power)wire, i get 12+ at the green (ground) when in START key turn, and less than 1 at the red(solonoid) at START key turn. Oddly enough the yellow wire is on the SOL post and the green is on the G post, but if i put the red on the SOL post i dont even get the CLICK. I may just swap my old one back in to see if it does anything.
I dont believe this would have anything to do with the ECM, turning over and not starting maybe , but not this. I have tried a couple different configurations at the ignition relay to no avail .
As for the HEI ,I ran a direct line from the distributor to the fuse box for switched power, and the tach line from the firewall penetration to the distributor, it splices to a few othe branches but that's all factory.
I cleaned up some of the factory ground bundles and tied them to a SOLID ground linked to the battery.

 

Check out this thread

Ignition problem. On this same page on YJ Wranglers. Guy had similar problem and found that a so called parking switch was disconnected.

 

Thanks Db , but the link is broken.... I'd be interested to read it though....

 

Did the computer tie into the solenoid? I wonder if you could use the old school solenoid I pictured earlier. That is out of a 79 cj. Ill do some research on your clicking issue tomorrow.

 

Here is another thread on a different forum

http://www.jeepforum.com/forum/f12/yj-hei-1549483/