Calgary Jeep Association

4x4 Related Groups => Tech Talk => Topic started by: dunl on August 11, 2009, 05:02:30 PM

Title: Comanche won't start...
Post by: dunl on August 11, 2009, 05:02:30 PM
Okay, I have it here and I can't hear the pump. The gauges don't move at all when I turn the key, even though the engine cranks. So, no longer think it is the fuel pump. I believe that when the key is turned, the starter is engaging, but the truck doesn't know the key is on.

Is that possible? ECU fried?

cps was replaced already
Title: Re: Comanche won't start...
Post by: dunl on August 11, 2009, 05:05:27 PM
Oh yeah...was stolen once, and found with the guy driving it to work at Wal-Mart.  Crowfoot dealership replaced the column....possible wire screw  -up?
Title: Re: Comanche won't start...
Post by: Gearhead on August 11, 2009, 06:19:21 PM
Check the starter relay , it's beside the battery.

I have a brand new  genuine Mopar  starter relay if you need one.  I think I paid $60 for it.

There are also some fusible links that may have been damaged by  a thievery attempt , there are several that connect to the starter relay and distribute current elsewhere through the vehicle.
Title: Re: Comanche won't start...
Post by: dunl on August 11, 2009, 06:24:59 PM
Check the starter relay , it's beside the battery.

I have a brand new  genuine Mopar  starter relay if you need one.  I think I paid $60 for it.

There are also some fusible links that may have been damaged by  a thievery attempt , there are several that connect to the starter relay and distribute current elsewhere through the vehicle.

But the starter turns over, and strongly....and wouldn't explain the dead gages either, would it?
Title: Re: Comanche won't start...
Post by: Gearhead on August 11, 2009, 06:29:24 PM
Check the connections  @ the starter relay , there are several wires  and fusible links that exit there ,  which run other components than the starter .   
Title: Re: Comanche won't start...
Post by: dunl on August 11, 2009, 06:34:12 PM
Okay, it's a start. Thanks.
Title: Re: Comanche won't start...
Post by: rangerdanger on August 11, 2009, 08:08:58 PM
Dead guages but still turns over hmm might be ignition switch, I just replaced one in my blazer this week that had the same symptoms
Title: Re: Comanche won't start...
Post by: dunl on August 11, 2009, 09:14:10 PM
Ignition switch sounds likely, as I just bypassed the fuel pump via the pins in the relay section. Hummed great.

If it was a failed ignition switch, the engine would think it is turned off - even if the starter doesn't.  That would explain why it died on the PO halfway out of the garage.  And no matter what I do, it will continue to think it is turned off, right?
Title: Re: Comanche won't start...
Post by: cLAY on August 11, 2009, 09:37:26 PM
There is a white porcelian block on the fender by the battery with two wires coming out of it. It reduced voltage to the pump to reduce noise(its a resistor). If it goes the pump doesn't get any power. You can just pull the wires off and connect them together. The resistor isn't really needed. Its also a handy palce to see if 12V is going to the pump.

If you push the scrader valve on on the fuel rail do you get a good spray of fuel?

Does it have spark? Pull one wire off and put in a known good plug with the metal threads resting against something metal and grounded. Does it spark?
Title: Re: Comanche won't start...
Post by: dunl on August 11, 2009, 09:51:53 PM
Looks like it's the ignition switch:

http://www.comancheclub.com/forums/viewtopic.php?f=2&t=17906&p=182913#p182913

Jumped the pump and it immediately kicked in.
Title: Re: Comanche won't start...
Post by: dunl on August 12, 2009, 12:46:40 PM
Okay, the key cylinder is NOT moving the rod that goes to the switch....but also when I move the switch by hand, nothing happens.

Do I need a new key cylinder? And how do I remove it from this tilt steering column? (which is second hand, courtesy of a dealer, so no clue what shape it might be in).  I can't find an access hole to remove the cylinder.
Title: Re: Comanche won't start...
Post by: cLAY on August 12, 2009, 03:39:13 PM
Ofthen there is a small hole underneath the tumbler, insert a small drill bit in it to  push the release button. Key must be in the tumbler when doing this.

Before doing that though I would remove the ing. switch and try working it by hand. Its mounted on screws with oblong holes so its postion can be adjusted.

When you turn the key to "on" do you get any power to anything? Radio, wipers, turn signals, etc.
Title: Re: Comanche won't start...
Post by: dunl on August 12, 2009, 04:02:38 PM
I hate being internet taught. :(

Good news is that after it was pointed out that I had the dimmer switch instead of the ignition, I found one plug loose.  In it went, and on came gauges.

Now it is spitting every few seconds, trying to start.  I can hear the fuel pump and smell gas. But she doesn't want to catch...any ideas?

Thanks for all the help so far.
Title: Re: Comanche won't start...
Post by: Immortal on August 12, 2009, 06:46:31 PM
how are the plugs looking?
Title: Re: Comanche won't start...
Post by: dunl on August 12, 2009, 09:58:08 PM
Supposedly new, but that's on tomorrow's list.
Title: Re: Comanche won't start...
Post by: cLAY on August 12, 2009, 10:34:13 PM
and are the wires on in the correct order?
Title: Re: Comanche won't start...
Post by: dunl on August 13, 2009, 09:56:55 AM
Yes, but the distributor might be 180. Checking that today.
Title: Re: Comanche won't start...
Post by: dunl on August 13, 2009, 11:31:51 AM
Okay, I THINK the distributor was off by 180, but now that I have the notch on the crank pulley lined up with the timing marks, the rotor is between #1 and #4 on the cap.

Figured I'd ask how to fix this before I mess something up or do it the hard way. I assume I can just loosen the bolts and rotate it?

Thanks so far.
Title: Re: Comanche won't start...
Post by: dunl on August 13, 2009, 02:07:45 PM
Okay, they skipped a tooth.. so now that's fixed.

Spark plugs...oh yeah, they were changed....2 out of 6.

Like my wife says...."it probably died because of the loose ignition switch plug, but because they started messing with everything else...."
Title: Re: Comanche won't start...
Post by: dunl on August 13, 2009, 03:05:49 PM
New plugs, properly gapped, no luck.  :hmm:
Title: Re: Comanche won't start...
Post by: cLAY on August 13, 2009, 03:09:28 PM
Do you gwt any spark when test as I explained above?
Title: Re: Comanche won't start...
Post by: dunl on August 13, 2009, 03:23:39 PM
I tried, but no spark.  However, I singed some arm hairs yesterday when I put some WD40 in the intake.....figured I had spark.
Title: Re: Comanche won't start...
Post by: dunl on August 13, 2009, 04:01:34 PM
No, it's still the same, even with the distrib corrected.

And I don't think flamability was a problem.  ;)
Title: Re: Comanche won't start...
Post by: dunl on August 13, 2009, 07:16:35 PM
Okay...spark confirmed via new coil.

It seems that there is some kind of a blowback into the air filter from the engine...thoughts? Spark, but doesn't start with starting fluid...just a little more of a bang.
Title: Re: Comanche won't start...
Post by: dunl on August 13, 2009, 07:17:23 PM
Okay...spark confirmed via new coil.

It seems that there is some kind of a blowback into the air filter from the engine...thoughts? Spark, but doesn't start with starting fluid...just a little more of a bang.
Title: Re: Comanche won't start...
Post by: dunl on August 13, 2009, 08:30:30 PM
Okay, maybe I'm not getting fuel.  I pressed the schraeder valve, and a little blurp of fuel came out. That's it. With the key on, shouldn't that valve keep spraying fuel?  I never thought to check with the key before.

I checked under to look at draining, and noticed that one of the lines is loose...the feed line, near the tank. Soaks when I wiggle it....needs replaced, but would this mess with the pressure?  Wouldn't the pump keep feeding it until the system pressurizes, and if I kept the valve open, wouldn't that also make the pump keep running?
Title: Re: Comanche won't start...
Post by: dunl on August 13, 2009, 09:15:32 PM
I thought they ran depending on the pressure in the rail....must be a sensor somewhere?
Title: Re: Comanche won't start...
Post by: dunl on August 13, 2009, 10:05:50 PM
It's an 89. I have an 88 manual, looking now.
Title: Re: Comanche won't start...
Post by: dunl on August 14, 2009, 09:46:36 PM
So just to recap:

1. purchased non-running. Was told that it stopped while being backed out of the garage one day.
2. changed the cps to find that it still wouldn't start. No gauges, nothing.
3. jumped the pump, sounded fine.
4. found the loose plug on the ignition switch.  Gauges now, fuel pump when the key turns, but no start.
5. Distributor seemed to be off 180, and skipped a tooth.
6. Changed the plugs, properly gapped. 2 out of 6 were new.
7. New coil, as the older one gave indeterminate readings. Why not, eh?
8. New fuel filter, new gas,  premium at that.

Now, trying to check TDC again, I had a HELLVA hard time turning the crank at some spots compared to yesterday. Others, quite easy. 

Thoughts?
Title: Re: Comanche won't start...
Post by: cLAY on August 14, 2009, 11:42:02 PM
Now, trying to check TDC again, I had a HELLVA hard time turning the crank at some spots compared to yesterday. Others, quite easy. 

Thoughts?

That's normal, as the engine comes up on comprssion it gets harder.

Blowing back into the air filter sounds like a timing issue. Are the plugs all routed correctly? Is the dist in correct? I thought on that year you set the engine to TDC on cylinder #1 and then drop the dist in and lock it down. I thought it would only go in one way? Or is it still gear driven?

Did you check the porcelain block by the battery?
Title: Re: Comanche won't start...
Post by: dunl on August 15, 2009, 12:35:26 AM
That's normal, as the engine comes up on comprssion it gets harder.

I don't know Clay...it seems tougher than yesterday, and the 5 cylinder Mercedes diesel engine in the garage is easier to rotate.  :-\

Quote
Blowing back into the air filter sounds like a timing issue.


That's what I thought...

Quote
Are the plugs all routed correctly?

Yes.

Quote
Is the dist in correct?

I believe so.  The trailing edge of the rotor is just leaving the #1 terminal at TDC.

Quote
I thought on that year you set the engine to TDC on cylinder #1 and then drop the dist in and lock it down. I thought it would only go in one way? Or is it still gear driven?

Gear driven.  It seemed to be out one tooth, so I re-indexed it....still the same.

Quote
Did you check the porcelain block by the battery?

I tried jumping it, but it didn't seem to make a difference. One of the Packrats is coming by tomorrow to help out.  8) The one thing I haven't checked is the cam sensor.
Title: Re: Comanche won't start...
Post by: XJHERO on August 15, 2009, 12:39:42 AM
was the engine rebuit or the timming chain and gears done recently?may have a thought if it was....
Title: Re: Comanche won't start...
Post by: dunl on August 15, 2009, 12:41:33 AM
Nope.  Doesn't seem to have any stretch when I turn the crank.

I bet it is something incredibly schtoopid.  ;)
Title: Re: Comanche won't start...
Post by: esi on August 15, 2009, 12:49:43 AM
Maybe a dumb question, but are the wires on the distributor in the correct order and direction (CW or CCW) I ask because I pulled all my wires a while back and then put new ones on according the the firing order, then realised that I'd put them on for the wrong rotation.
Title: Re: Comanche won't start...
Post by: dunl on August 15, 2009, 12:56:13 AM
Yeah, I've checked them a few times.

But also enough time to screw something up too. lol
Title: Re: Comanche won't start...
Post by: cLAY on August 15, 2009, 10:47:23 AM
Getting a gear driven dist in right can be tricky. Especially if it has a notch on the bottom for driving an oil pump, if you try to move the dist back one gear tooth you may need to reach down into the hole with a long flatblade and turn the oil pump back manually so it engages properly.

How mush pressure is at the rail after cranking for 15-20sec? There should be a good healthy spray when you press on the schrader. A fuel pressure guage can be purchased at CT for about $40. Just don't get fuel on the plastic face of the guage.

When you say you jumpered the porcelain block you mean you unhooked the wires from the block and hooked them together right?
Title: Re: Comanche won't start...
Post by: dunl on August 15, 2009, 06:49:50 PM
[size=200]"It's alive....ALIVE!!!"[/size]

(http://www.zurb.com/word_uploads/0000/0031/its-alive.jpg)


 :clapping:  :bowdown:  :D  :rock on:

Had a friend come over with a fresh set of eyes to look, found my dyslexic spark plug mistake, and we reindexed the distrib at TDC.

However, at around 80km or so, we both found out what Death Wobble feels like.  :(
Title: Re: Comanche won't start...
Post by: cLAY on August 15, 2009, 08:54:46 PM
Thats a whole other thread....... ::)
Title: Re: Comanche won't start...
Post by: dunl on August 15, 2009, 09:14:24 PM
Yup. lol

Thanks for the help guys.  ;D