84 CJ7 258, now-- no click at solenoid, no crank. (Was hard start and engne cut out when warm)

Tiny
AKMILSURP
  • MEMBER
  • 1984 JEEP CJ7
  • 50,000 MILES
Greetings from Alaska,

Having a bear of a problem with my 1984 CJ7 Laredo. This is a MUCH modified CJ. 1979 258 block, .030 over, 4.0 HO head, Crane 260H cam, Clifford Headers, Fisher harmonic dampner, 258 manifold modified by Clifford modified to fit 4.0 head, Howell "California" TBI conversion, Jacobs "Prostreet" ignition Triggered by a Ford TFI coil, and Jeep OEM Ford Duraspark ECM, (since I use a GM ECM for the TBI, I don't use the Stock EECU. Ignition is wired direct instead of going through EECU) As much of a mechanics nightmare this may seem, it's been running like a top for about ten years with this configuration.

I had been experiencing hard start issues, and/or sudden cut out of the engine after driving enough to warm it up. THen I had to wait about an hour, and it would start? Go figure. I started throwing parts at it, when I should have been troubleshooting via wire diagram and a Multimeter. My TBI is essentially a Chevy 1990 4.3 V6 TBI set up without ignition control. It uses the following sensors: MAP, CTS, TPS, Heated O2. Also a fuel pump relay, and I use an in-line external fuel pump (Airtex E-2000), with a standard 500 CFM 4.3 TBI unit with adjustable fuel pressure regulator. "Alterstart" 180 amp alternator, and "Alterstar"t gear reduction starter.

Basically, it was losing reference pulse intermittently, causing it to either not start--OR die on me at the most inopportune time. Sooooo following advice from a few well meaning individuals---GRRRRR - I started Replacing sensors and electrical parts in this order:

1. Duraspark module-- seemed to fix for a bit. Then back to it's old tricks
2. Fuel Pump relay- ditto
3. Fuel Pump- ditto
4. Distributor Assy.- Ditto
5. TPS- Ditto
6. GM ECM (For TBI 1227747)- ditto
7. MAP- AND- Ignition Switch-- Ditto
8. Howell "Tach filter" (provides square wave for GM ECM to generate reference pulse, this had to be removed from the wiring harness, and a new one soldered in at the connections.)-
At this point it ran well for about an hour, then died about 6 miles from the house. I waited an hour. Then it started right up.
I finally got it home, and. Continued troubleshooting

9. Reference pulse wire to ECM- I thought the connections might be bad, so I removed the crimp connectors and soldered all the junctions and re- taped them.

10. Starter Solenoid- While I was at it I swapped in a new starter solenoid for good measure.

11. TFI Coil- -- why not, they're cheap.

After I did the last three items, the jeep fired right up, but would not keep running, I had to keep blipping the throttle to keep it going. I said hell with it and called it a night.

SO. The next day I figured Maybe it's not getting enough voltage to the coil. VIOLA- sure enough it was only getting 2.8 volts with the ignition in the "Run" position. I removed the tape from the wiring harness to find the end of the Resistance wire to the coil. I pulled off the bullet connect.2.8 VOLTS? Followed resistance wire to it's tie in point near the fuze box. I removed it. It ohms correctly, but I can get Full battery voltage at it's tie in point!

OK then. Resistance wire is BAD. Since a Ford TFI EEC COil runs full bat power, and the Duraspark ECM does as well, I made a 10 guage jumper wire and ran it in place of the resistor wire to give the TFI coil full Batt power.

I figured this will solve the weird issues.

I hook everthing up---- and. Now the engine won't crank. Battery power is good. I can't even hear the solenoid CLick! All fuzes good. I need to have someone put the ignition switch in the start position so I can check voltage to the light blue wire on the solenoid. I should get voltage there IF the ignition is in start position. I even swapped in another spare solenoid. No Dice.

I didn't touch any of the starter power wires when I was fixing splices.

Generally I'm pretty good at mechanical/electrical issues- this one has me stumped though!

I think if I get it to crank, the ignition reference pulse and coil power issues will be fixed. I hope. Any ideas on the "No CLick" No crank issues? Or anything else?




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Thursday, May 2nd, 2013 AT 8:17 PM

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Tiny
CARADIODOC
  • EXPERT
I'll try to help if I can. You should have a Ford starter solenoid, Ford starter, and a Chrysler automatic transmission. The neutral safety switch will be at the left rear of the transmission, right above the pan. In the circuit it is in the ground side of the coil of wire in the solenoid.

There's two versions of that solenoid. One is for what you have. The two ends of the coil are connected to the two small studs. The other version has one end of the coil still connected to the left smaller stud next to the large battery stud, but the other end is attached to the mounting bracket. The second smaller stud gets 12 volts switched onto it during cranking to bypass that ignition resistor.

Step one is to check for voltage to the ignition switch wire that you said is blue. I found a diagram on the internet but I can't make out the wire color. I also have an '84 Mitchell Manual but the closest thing they have is an Eagle. That shows the light blue wire going to ground through the neutral safety switch, and a dark green coming from the ignition switch. That's the one that should have 12 volts during cranking.

Regardless, one of the two smaller wires has to get 12 volts with the ignition switch in the "crank" position. Look for that on both wires. If you find it, use your ohm meter to measure the other small wire to ground. It should be very low in "park" or "neutral".
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Thursday, May 2nd, 2013 AT 9:30 PM
Tiny
AKMILSURP
  • MEMBER
Yes-- Ford style solenoid is what the Jeep uses. THe starter is an aftermarket gear reduction unit for faster crank, is MUCH lighter, etc, but. Still operates under the same principles as the Ford starter would. Gotta have Juice to Crank!

I think I'll just jumper the pole under the starter (that goes to the neutral Start Switch) to ground. In effect, the NSS just provides a ground to the relay. If it starts, that should tell me if the NSS is defective. I'm doing a transmission swap upgrade to an GM 7004R (with adapters of course) soon. If it is indeed the switch, I can live without replacing the switch and having it jumpered to ground until I do that.

THe Chiltons manual for Jeep CJ's have excellent wiring schematics that show the wire code colors.

I'll let you know what happens!
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Friday, May 3rd, 2013 AT 10:51 AM
Tiny
CJ MEDEVAC
  • EXPERT
OUR SITE IS BEING "REMODELLED" .......PICS AND DIAGRAMS AIN'T SHOWING UP...EVEN ON SOME OF THE OLDER POSTS

I'M GONNA GIVE YOU A COUPLE OF LINKS THAT MAY HELP YOU.......I'D LIKE TO SEND SOME RECENT PICS.....IT JUST AIN'T WORKIN'!

THIS MAY BE "OLD NEWS"......LOOK IT OVER ANYWAY!

http://www.2carpros.com/questions/1996-chevrolet-tahoe-wont-start-sounds-dead-battery-jumpbox-get-same-reults

THIS ONE MIGHT EXPLAIN "MY WAY" OF HOOKING UP THE SOLENOID. LOOK OVER HOW ITS ALL CONNECTED.....AND THE EXPLANATIONS

http://www.2carpros.com/questions/1985-jeep-cj7-1985-jeep-cj7-no-spark

SEE MY 1ST DIAGRAM ON PAGE 3

http://www.2carpros.com/questions/1979-jeep-cj7-79-that-started-ran-prior-problem-now-wont-start-get-spark-out/page/3

I'VE GOT QUITE A FEW PICS OF THE IGNITION SWITCH---TORN DOWN---AND MODS I MADE FOR MINE....JUST CANNOT POST 'EM AT THE PRESENT TIME

LEMME KNOW IF ANY OF THIS HELPS OR IF YOU NEED ME TO KEEP TRYING LINKS OF STUFF I'VE ANSWERED IN THE PAST

GONNA TRY A PIC BELOW, TO SEE IF IT'S WORKING YET!

THE MEDIC

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Friday, May 3rd, 2013 AT 12:49 PM
Tiny
AKMILSURP
  • MEMBER
SUCCESS! Frustration got the better of me. Sometimes you just need someone else looking at it externally. I kept thinking "Naw, that couldn't be it". Grins.

I jumpered the Neutral start Switch terminal on the bottom of the Starter solenoid direct to ground. She started right up. So Ignition switch, solenoid, and starter are good. (From original post, the solenoid and ignition switch were new).

Replacing the malfunctioning resistance wire, (that normally powers the coil in the run position) to the TFI coil (which by design can run full battery power, where the stock coil can't) with a 10 gauge jumper solved the previous "start, but no run" issue. Went from 2.8 VDC at coil in run position to 12+ VDC!

SOOOO. The hard start and cut out while running (and warm) issues appear to be fixed at this point; an extended test drive will tell. (I'm pretty sure I got it though)!

Look at the bright side, I have lots of new electronics and sensors now. (And now, a full set of spares) Think of it as an UBER tune up. LOL
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Friday, May 3rd, 2013 AT 1:21 PM
Tiny
CJ MEDEVAC
  • EXPERT
ALONG WITH A "GET BY" SET OF TOOLS

. AND "NORMAL SPARE PARTS".I CARRY THESE FOR SPARES TOO. FUEL PUMP. IGN MODULE. COIL

STUFF THAT HAS LEFT ME STRANDED BEFORE

I RECKON "I" TERMINAL GETS YOU BOOSTED AT START UPRESISTANCE (WIRE OR BALLAST) HAS YOU RUNNING IN THE IN THE "ON POSITION". AS PER MY DIAGRAM?

THE MEDIC
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Friday, May 3rd, 2013 AT 3:49 PM
Tiny
CJ MEDEVAC
  • EXPERT
WHOLE TOP OF PREVIOUS RESPONSE IS MISSING. AIN'T GOT TIME TO RE-WRITE IT NOW. CHOW TIME, SHE'S LEAVING ME BEHIND!

THE MEDIC
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Friday, May 3rd, 2013 AT 3:51 PM
Tiny
AKMILSURP
  • MEMBER
Exactly, CJ! That's why it ran like crap after initial start up two days ago after I cleaned up and soldered the connections for reference pulse to the ECM.

THe resistor wire was bad, so on initial start up it got full power to coil from the solenoid, after the ignition switch returned to "Run" position the coil was only getting 2.8 volts. No wonder it wouldn't run! Lol Now it gets full batt voltage to the TFI coil which can easily handle it.

And now that the "won't crank" is fixed. We're on the road again!

BTW I've owned this CJ for over 20 years, and do most of my own work and mods. And it has A LOT lol

THanks again for your help!
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Friday, May 3rd, 2013 AT 6:25 PM
Tiny
CJ MEDEVAC
  • EXPERT
DO A GOOGLE SEARCH

2CARPROS CJ MEDEVAC

THEN HIT "IMAGES". SOME OF MY MODS CAN BE SEEN IN THE OLD POSTS I'VE ANSWERED

RETURN TO THIS POST IF YOU WANT TO INSURE YOU GET A HOLD OF ME, KEEP ASKIN' ----I'VE ALWAYS HAD A CJ. SO FAR 7. THE LAST 2 SINCE 1991

POST A PIC OR 2 OF YOURS

THE MEDIC
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Friday, May 3rd, 2013 AT 7:01 PM
Tiny
AKMILSURP
  • MEMBER
Glad to post a pic!
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Friday, May 3rd, 2013 AT 7:59 PM
Tiny
CJ MEDEVAC
  • EXPERT
NICE JEEP!

COME BACK TO SEE US SOMETIME!

THE MEDIC
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Saturday, May 4th, 2013 AT 7:53 PM
Tiny
AKMILSURP
  • MEMBER
Well then. Finally took it for a test drive. So. It cranked right up and ran great. I got about 3 miles from the house, and noticed the Oil pressure gauge was not working. Set brake, put in park, and jumped out with it still running, lifted the hood and found the wire to the oil pressure sender unit had come uncrimped. So got out my Leatherman, recrimped. VIOA! The gauge is working again. Excellent oil pressure. I was about the shut the hood, and @*%$! The jeep engine cut off.

Tried to restart. Cranks, fuel pump relay kicks in, fuel good to TBI. No gas spraying from injectors on TBI.

Let it cool down 2 hours. Still no start same issue. I'd say no reference pulse to GM ECM for TBI system. ARGGGGGG FREAKIN' MADDENING!

Towed the @*&$%! CJ back home, of course not enough manpower to push it up driveway and into the garage. THank god for winches. WInched it up the driveway to the garage door, then into the garage. (An old Scissors jack jammed into the iron pipe floor drain makes a good anchor point! Lol)

Soo there has god to be a relay or other wiring issue, perhaps chafed wire, that ONLY acts up when warm.

My wiring harnesses are all taped and zip tied secure, so this is gonna be a bear.
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Monday, May 6th, 2013 AT 12:19 PM
Tiny
CJ MEDEVAC
  • EXPERT
Caradiodoc. THIS NEW COMPUTERIZED STUFF IS UP YOUR ALLEY!

IT'D BE NICE IF IT WAS A "NO SPARK" SITUATION AND THE IGNITION MODULE GOING BAD WHEN IT GOT HOT.I COULD TALK YOU ALL THRU THAT

I EVEN HAVE PICS OF HOW TO BYPASS THE IGNITION STUFFHOWEVER, I DON'T THINK THAT WOULD POWER UP YOUR INJECTORS

IF YOUR WIRING HAS NOT BEEN TIED UP AND HAS BEEN BOUNCING AROUND FOREVER. MAYBE SOME JIGGLING/ TUGGING/ PULLING ON THE WIRES AS THEY ENTER YOUR "APPLIANCES" (ANY AND ALL). WHILE YOUR BUDDY ATTEMPTS TO CRANK IT UP. EVEN A "JOLT OF BUSTING OFF" MIGHT GIVE YOU A HINT THAT YOU ARE PLAYING IN THE RIGHT AREA!

Caradiodoc MIGHT GIVE YOU BETTER INFO ON WHAT TO TEST 1ST, WHICH DIRECTION TO FOLLOW AS YOU GO. PROVIDE HIM WITH ACCURATE TEST INFO, SO HE CAN LEAD YOU THRU THE PROCESS

. HE WAS/ IS AN AUTO MECHANICS TEACHER, REALLY KNOWS HIS STUFF TOO!

I'M STILL IN THE CARB AGES

I'M WATCHING Y'ALL

SOME GOOD UNDER-HOOD PICS MIGHT AID US TOO

THE MEDIC
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Monday, May 6th, 2013 AT 4:24 PM
Tiny
CJ MEDEVAC
  • EXPERT
1ST HALF OF LAST ANSWER. IN BERMUDA TRIANGLE NOW

THE MEDIC
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Monday, May 6th, 2013 AT 4:25 PM
Tiny
AKMILSURP
  • MEMBER
I'm a fanatic for taped and secured wiring-- learned from my 26 year USAF career. So literally nothing is loose or moving around in the engine bay or anywhere else in the Jeep.

I think the 10 gauge wire I sliced in to replace the bad resistance wire, cooked the DuraSpark Ignition module. Some posts I've seen suggest the Duraspark Module is only designed to handle 9 volts back from the coil in stead of 12. Others say don't worry about it if you use a TFI coil or similar aftermarket E-coil. I think more than 9 VDC cooked my module. It lasted about 15 minutes LOL, and the TFI coil got so hot you couldn't touch it.

Some folks say it works, others say the module with last 10 minutes to a couple months then goes PFFFFT.

THe resister wire is #ICR 22 From Napa they said it costs $24. You have to ask specifically for it as their books don't show it as a Jeep application. I bought an old style ballast resister, but it didn't provide enough resistance. YOu need 1.35 ohms, the ballast resistor was 1.2 ohms, so I didn't install it. THe last time I replaced one was in January 2001. (Same Jeep-- Similar issues) I had forgotten about it.

So the new #ICR 22 resistance wire should be in tomorrow, and I'll pick up another Ignition module (under warranty lol) at the same time

I keep records on the CJ like you would for an AIrcraft. (I did learn some thing useful from my USAF Days)!
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Monday, May 6th, 2013 AT 5:00 PM
Tiny
CJ MEDEVAC
  • EXPERT
SO YOU 'ARE' USING ONE OF THESE?....1ST PIC

SEE MY "MAY 5TH" ANSWER IN THIS POST.....NEAR THE BOTTOM OF THE ANSWER, REGARDING THE MODULE

http://www.2carpros.com/questions/1977-jeep-wagoneer-77-360-begun-dying-random-only-happens-on-longer-drives-say

WE WOULD GET ALONG REALLY WELL FLY-BOY!......SEE MY ANSWER IN THIS ONE

http://www.2carpros.com/questions/2008-hyundai-tuscon-life-time-brake-pad-warrantees-good-value

PAP RETIRED USAF IN '74.......THIS WAS THE OPEN COCKPIT OF THE NEWEST AF BIRD IN THE HANGER, LATER HE BOARDED AND TOOK TO SEE THE GREAT WING COMMANDER IN DEC 2010.......2ND PIC

WHEN I GOT IN THE ARMY, THEY TOLD US THAT "LANDING" WAS THE MOST DANGEROUS THING TO DO IN AN AIRPLANE .......SO I BECAME AN AIRBORNE RANGER AND I GOT THE HECK OUT OF 'EM (WHEN I COULD) BEFORE THEY LANDED!.....3RD PIC IS A GLIMPSE OF MY MAN CAVE

THE MEDIC
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Monday, May 6th, 2013 AT 6:07 PM
Tiny
CJ MEDEVAC
  • EXPERT
PIC 3. FRONT AND CENTER!
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Monday, May 6th, 2013 AT 6:10 PM
Tiny
CARADIODOC
  • EXPERT
The difference between 1.2 ohms and 1.35 ohms is insignificant. Most resistors, if not specified otherwise, have a 10 percent tolerance. The point is there is something there to limit current to a safe value.

That voltage you're measuring can be misleading too. The current is going to be pulsing and so will the voltage dropped across the resistor. Digital voltmeters take a reading, think about it a while, then display it while they take another reading. The actual voltage might vary from 14.0 volts to 8.0 volts, as an example, and the display on the meter will bounce around. You need an old-style meter with a pointer to give an accurate average reading. There could also be a capacitor in the module or in the circuit to smooth out those voltage pulses. That would help a digital meter read the average voltage better, but I still wouldn't put a lot of faith in it.

I never paid much attention to the resistor values in the past. I just checked them for continuity. I DO know the older Chryslers used 1.2 ohms to limit current flow through the breaker points to less than an amp. That was enough to create a nice strong spark. The later electronic systems also used 1.2 ohms for one of the two resistors. GM used that resistor wire which did the same thing, but I never ran into a bad one or measured one to know what normal is.

The goal is to get as much current flow as possible through the ignition coil to build a really strong magnetic field, but that current has to be switched on and off by the module. If there was no resistor in series, the only thing limiting current to a safe value would be the coil's resistance, and that's not much.

It's a pain to go back and reread some of the earlier replies when I have to switch between "page 1" and "page 2", so just let me ask instead, did you measure the old resistor wire, and if so, what did it read? I found a Ford diagram from 1980 with the TFI module. That used a 1.1 ohm resistance wire, so you should be safe with a regular 1.2 ohm resistor. We know from that diagram that it will work properly with that value and give enough spark voltage, but I can't tell if they bypass it during cranking to make up the lower battery voltage.
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Monday, May 6th, 2013 AT 8:10 PM
Tiny
AKMILSURP
  • MEMBER
OK-- Pics of my Jeep's engine bay, Needless to say, this ain't your average CJ7.

One pic shows the end of the 10 ga jumper wire I used to replace the resistance wire with. THe others show the battery, Jacobs pro-street, large cap conversion of Motorcraft distributor, TFI Coil, well taped and tied down wiring, the TBI unit, 4.0 head on '79 258 block, Headers, O2 sensor, and about 48 feet less vacuum hose than there was before I did the TBI conversion in 1998. No pulse air valves. Other AMC/Jeep emission do dahm (Other than EGR and PCV)

I ordered the #ICR22 resistance wire replacement, and another Duraspark module. I think that should do it!

For good measure I'll the module tested first. (Assuming the store has a tester)
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Monday, May 6th, 2013 AT 9:11 PM
Tiny
CJ MEDEVAC
  • EXPERT
NICE PICs!

. NOW I GOTTA QUESTION. WHERE'D YOU GET THE VALVE COVER?

LET US KNOW HOW IT'S GOING

THE MEDIC
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Tuesday, May 7th, 2013 AT 1:16 PM
Tiny
AKMILSURP
  • MEMBER
Yes I did, at first it measured 1.2 ohms, and when ignition is at the "run " position, I only got 2.8 volts to the coil! THe jumper wire gave me 12.48 VDC. Ran great until I think it fried the Durapark module. Got a new module, and the replacement Napa #ICR 22 resistance wire. Hopefully once I swap them in, it will fix the issue. I don't think it cooked the TFI coil, but if it did I have a spare TFI coil & new Accell super coil I can use. Both a "ecoil" type

Oddly enough the resistance wire measured 1.8 owns the next day when I rechecked it. It definitely has issues. I replaced it about 10 years ago for a similar issue, if memory serves.

"It's a pain to go back and reread some of the earlier replies when I have to switch between "page 1" and "page 2", so just let me ask instead, did you measure the old resistor wire, and if so, what did it read? I found a Ford diagram from 1980 with the TFI module. That used a 1.1 ohm resistance wire, so you should be safe with a regular 1.2 ohm resistor. We know from that diagram that it will work properly with that value and give enough spark voltage, but I can't tell if they bypass it during cranking to make up the lower battery voltage".

THe Head is from a Jeep 4.0 HO, I believe that's the stock aluminum valve coever for a 1994 Jeep 4.0 head. I just painted it black and found a grommet to run the PCV out of.
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Tuesday, May 7th, 2013 AT 2:26 PM

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