Hey guys/gals, im almost ready to quit and turn this over to a real mechanic. I built what should be a 4.7 stroker from my 1999 XJ stock 4.0. It needed a head gasket so I figured id go all out. Its a nice build i enjoyed it however i never gave much thought to the electronics. The last truck i rebuild was a 1979 4x4 Dodge Van with an electronic choke thats about it.
When I finished my XJ I had a heck of a time getting her timed properly but after indexing the dizzy 3 times I got it. Wow man SHE fired up and sounded great, i ran up the rpms a bit to break in the cam, my God I couldnt wait to get her out on the street or better on the trails. I had some lights I was finishing upa but everytime i went out to work on her id fire her up until one day it wouldnt start again. I pulled the #1plug no spark, i checked the CPS which seemed ok 6.47 ohms pin A &B infinate on pins B & C. Im lacking any skills whatsoever in the computer systems and sensors and dont know what to check next. Can anyone give me any tips on what to check or an order in which to test different things? Should I just swallow my pride, admit defeat and call the hook to drag her to a mechanic shop? Any help would really be awesome...

 

No spark but you kept going?

You need to verify spark at each plug, verify wires are good, coil works, and cap rotor is good...report back
.

 

Ok Thanks for your feed back I'm going to check the other plugs, coil ETC. and report back like you said. I'll be back soon. All the items you mentioned are new owever I know that doenst make a difference...

 

Around these parts, we call it noggin pokin. LOL

Always verify first...follow basic troubleshooting steps, we will get you through this bud

 

My Noggin hurts Ronin, I think I put a dent in it yesterday LOL, So I checked all the plugs for spark, and no spark. I checked the coil, no spark, the cap, rotor, wires, are all new form the rebuild however I know that doesn't mean anything something can still be bad. I'm not sure how to test the cap or rotor aside from a visuale inspection which looks fine to me. Insidently I tested these things with the key on and off.

 

No spark at coil? Have you verified crank position sensor yet?

 

'99 has coil rail.

 

Thought rails were on 00-01.

OP, can you verify?

 

Yeah I think your right ronin my 99 doesn't have a coil rail, its a single coil. Yes If I did it right the CPS ohm'd out at 6.47 between pins A & B, Infinate on B&C

 

Nice Jeep Cobra

 

Any engine codes?

 

My brain fart.
'99+ has 'horseshoe/curved' intake manifold
'00+ has coil rail

Too many Jeeps and too many differences.

 

Let everyone take note here.

THIS is how you troubleshoot.

Doesn't mean the answer is easy,

That said, we've already eliminated what it isn't. Now, we need to eliminate what ELSE it isn't.