XJ want start - Pirate4x4.Com : 4x4 and Off-Road Forum

biggin · 03-24-2004, 03:20 AM

Ok guys this one has me stumped.
Ive got a 90 xj 4x4 with the 4.0 and auto in it. I baught it off a pbb member knowing that it didnt run due to running it in a mud hole.
The thing is I ve got fire and fuel going to it but it still does not hit a lick. Ive changed the cps on it, changed oil, and tripple checked the timing. It does have compresion and a pretty decent spark to the plugs. The guys that had it before me had swapped the computer, coil, and about everything else electrical inside the cab.
Is there something im missing? I figured since ive got fuel and fire and in time it should do something. Any help will be appreciated.

DevilJeep · 03-24-2004, 03:27 AM

Try holding the throttle about half way and try to start it........had this happen to me once, had spark and fuel, but no start. Held half way and it started anfer a few seconds.

Edit: it was on an 90 XJ too.
Hope that helps!

biggin · 03-24-2004, 04:18 AM

Ive held it half open wide open and even sprayed starting fluid down the intake. Nothing. I have got a few random hits every once in a while but it is very weak.

biggin · 03-24-2004, 11:06 AM

Come awn

some one has to have some ideas?

Damage, Inc. · 03-24-2004, 12:01 PM

You've got fire (you said pretty good spark tho...blue kernel or yellow?) As I recall, a yellow spark is considered weak; it should be blue, but I don't remember exactly. I'm just throwing out ideas here!

You said you squirted starting fluid so that *should* eliminate any fuel delivery problems (meaning it if doesn't start on starting fluid, something else is amiss), so look to the spark/timing.

offroadman83 · 03-24-2004, 12:20 PM

Did you check the relays on the passenger side of the motor. Sometimes they can cause this. Also check under the coil and test out the control module there.

biggin · 03-24-2004, 12:57 PM

The spark is definetly yellow but looks wide and strong. The timing is spot on so I know it hasnt jumped time. I have an extra distribitor or 2. Ill swap that out and maybe new plugs wouldnt hurt.

biggin · 03-25-2004, 12:16 PM

monkeyevil · 03-25-2004, 02:03 PM

Throw your timing light on the coil wire. It should get all strobe light on you. If it's not replace the coil or CPS.

Where is the compression at?

03-24-2004, 03:20 AM	#1 (permalink)
biggin Registered User Join Date: Aug 2003 Member # 22183 Location: e.tn Posts: 1,231	XJ want start Ok guys this one has me stumped. Ive got a 90 xj 4x4 with the 4.0 and auto in it. I baught it off a pbb member knowing that it didnt run due to running it in a mud hole. The thing is I ve got fire and fuel going to it but it still does not hit a lick. Ive changed the cps on it, changed oil, and tripple checked the timing. It does have compresion and a pretty decent spark to the plugs. The guys that had it before me had swapped the computer, coil, and about everything else electrical inside the cab. Is there something im missing? I figured since ive got fuel and fire and in time it should do something. Any help will be appreciated.

03-24-2004, 03:27 AM	#2 (permalink)
DevilJeep Registered User Join Date: Dec 2003 Member # 25556 Location: Going down to Buckeye Posts: 249	Try holding the throttle about half way and try to start it........had this happen to me once, had spark and fuel, but no start. Held half way and it started anfer a few seconds. Edit: it was on an 90 XJ too. Hope that helps! __________________ . Last edited by DevilJeep; 03-24-2004 at 03:28 AM.

03-24-2004, 12:01 PM	#5 (permalink)
Damage, Inc. Rock God Join Date: Jun 2003 Member # 20298 Location: Colorado Posts: 1,153	You've got fire (you said pretty good spark tho...blue kernel or yellow?) As I recall, a yellow spark is considered weak; it should be blue, but I don't remember exactly. I'm just throwing out ideas here! You said you squirted starting fluid so that should eliminate any fuel delivery problems (meaning it if doesn't start on starting fluid, something else is amiss), so look to the spark/timing. __________________ I didn't read what he said, but he's right. - BHC

03-25-2004, 02:03 PM	#9 (permalink)
monkeyevil Registered User Join Date: Nov 2001 Member # 7978 Location: Kalamazoo, MI Posts: 1,038	Throw your timing light on the coil wire. It should get all strobe light on you. If it's not replace the coil or CPS. Where is the compression at? __________________ [URL="http://www.jcroffroad.com"]http://www.jcroffroad.com[/URL] [QUOTE=welndmn;10381954]You should build your rig so the weak link is traction :) I run slugs myself.[/QUOTE] Last edited by monkeyevil; 03-25-2004 at 02:05 PM.

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03-24-2004, 04:18 AM	#3 (permalink)
biggin Registered User Join Date: Aug 2003 Member # 22183 Location: e.tn Posts: 1,231	Ive held it half open wide open and even sprayed starting fluid down the intake. Nothing. I have got a few random hits every once in a while but it is very weak.

03-24-2004, 11:06 AM	#4 (permalink)
biggin Registered User Join Date: Aug 2003 Member # 22183 Location: e.tn Posts: 1,231	Come awn some one has to have some ideas?

03-24-2004, 12:20 PM	#6 (permalink)
offroadman83 Rock God Join Date: Oct 2001 Member # 7624 Location: McAllen,Tx Posts: 2,293	Did you check the relays on the passenger side of the motor. Sometimes they can cause this. Also check under the coil and test out the control module there.

03-24-2004, 12:57 PM	#7 (permalink)
biggin Registered User Join Date: Aug 2003 Member # 22183 Location: e.tn Posts: 1,231	The spark is definetly yellow but looks wide and strong. The timing is spot on so I know it hasnt jumped time. I have an extra distribitor or 2. Ill swap that out and maybe new plugs wouldnt hurt.

03-25-2004, 12:16 PM	#8 (permalink)
biggin Registered User Join Date: Aug 2003 Member # 22183 Location: e.tn Posts: 1,231