'97 XJ won't start...and no codes

If the main ground for the body goes bad, the computer won't turn on. On the older ones, this is a mesh strap from the rear of the engine head to the firewall.

There are more computer grounds on a bolt by the dipstick.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's - Gone to the rust pile... Canadian Off Road Trips Photos: Non members can still view! Jan/06 (More Off Road album links at bottom of the view page)

The first thing I would suspect here is the crank position sensor. It will not always code. (it only codes if coil opens up not usually if the sensor is weak and not triggering right. When it is bad, you will not get any fire at all. Check it before you go on a wild goose chase like suggested above. If sensor is good then go to plan "B" the goose chase but the CPS's do go bad with age and can fail suddenly.

----------------- TheSnoMan.com

So a failed CPS will prevent the computer from showing any codes eh.

Stalking Moron.

Mike

It can. There is a coil in it that if it opens it will show a failure but if the magnetflux is weak in it to the point it will not send a strong enough trigger pulse it may not code at all.

They do go bad (it is not rare at all) and do not always code and you would know this if you were not the Moron here.

----------------- TheSnoMan.com

Illiterate too eh.

His symptoms that I addressed are the computer showing no codes, period!

If you had bothered to read the original post or even my reply instead of stalking me you might have seen that.

Once again you have proven you have no clue in the world.

The CPS 'connection' is the part that normally goes bad for a die while running and if you had ever touched a Jeep, you might know that.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's - Gone to the rust pile... Canadian Off Road Trips Photos: Non members can still view! Jan/06 (More Off Road album links at bottom of the view page)

Yes you are

No surprize. I have seen CPS fail without coding. It may not be bad but given age it should be checked first.

I read it did you? (you just think you did)

No you have about yourself as usual

Again the Moron. They can run fine one day and not start the next with a bad CPS and also run for a bit then quit and then run again for a bit. You would know this is you really had any usable knowledge. (I bet you farm out any repair past using duct tape)

You should stick to your patented tips like burning rubber in reverse in 4wd to relieve driveline wrapup stress and forgetting about 5 gear on your 5 speed because you run tall "power " gears with big tires that you think is a great combo but results in a power loss in all gears and increased drive line strain (this plays well with you stress relieving method too). Do not forget telling them about how to shift into 4x4 at 70 MPH for ego boosts (and a good way to get a one way tick to ditch on a slick surface) and how to use low range often on the road because you need it with cobbed together ego boosting but powerless setups like yours. I have owned and been around Jeeps and

4x4's longer than you today and likely you never well catch me unless a die in next 20 or 30 years and you live to be 100 while still owning them. People like you give Jeep a bad name and you a a disgrace to the whole Jeep image and thing. You would not know what a real Jeep was or is supposed to be even if it bit you. You are one of those wanna be's that Jeep commercails today is aimed at. You are a big "JOKE" Mike as a Jeep guy!! Knock yourself out.

----------------- TheSnoMan.com

First thing I'd check is fuel pressure and pull off some from the rail and check for contamination/water just in case you tanked up on bad fuel.

Next is the spark. If the coil goes out it doesn't throw codes.

Wouldn't hurt to check fuses either. Usually the computer throws 12 and

55, but I'm not sure if it does a 55 if there are no codes to show. Pulling and replacing the battery ground will set a code 12.

His Jeep's computer doesn't show 'any' codes you stalking foole!

Not even a code 55 if you had of bothered to read it instead of focusing on stalking me.

He asked if the computer was dead, I pointed at grounds.

You are stupid beyond belief.

Mike

You really should familiarize yourself with Chrysler diagnostic strategies before you touch a keyboard.

If this were one of your clapped out 80s GM trucks and it wouldn't flash a KOEO code 12, where would you start looking?

Well, I don't have a spark. So that would logically eliminate a fuel problem. But, shouldn't I still be getting at least a 55 code? Usually, I can pull up that code and no others when there is nothing wrong. I pulled the positive cable off the battery, I'm guessing I should have pulled the other one instead to try and reset to a 12 code?

I did check the fuses, but really couldn't tell what any of them go to outside of the big relays. However, when pulled, all the fuses did look good.

I don't think this is really relevant, but incase it is, the xj was serviced about 3 weeks ago, I had the spark plugs and wires replaced. I have 141,000 on the Jeep.

thanks for all the suggestions.

Sandy

Thanks for the info on the ground. After a little more poking, I have found there is no spark. So, would that still be a symptom of a bad ground as well as there still being absolutely no codes whatsoever appearing?

Thanks,

Sandy

Thanks for the suggestion. If the CPS was indeed bad, would i get a spark still? Or is that another indication that it could be the CPS?

thanks,

Sandy

Yes, you would still get a spark, but only a few before the computer detected no CPS signal and removes power to the coil.

You need to check for spark.

Wasn't 97 the year that the on-of-on-off-on trick wouldn't display codes? There was a short run of those AIR. BTW, which engine? Most of the rest of this assumes the 4.0L six.

Ground strap first, fuel pressure second: do you hear the pump when you turn the key on (before the starter engages)? Remove the cap and press the pin in the center of the schrader valve on the fuel rail (use a rag) to see if it's holding any pressure. Unplug and re-plug the CPS connector - they lose contact, so clean it with contact cleaner or WD40.

Use a spare plug and check for spark on one or more plug wires, come back for more ideas once we have a better idea of what is/is not happening.

God Bless America, Bill O|||||||Omailto: snipped-for-privacy@aol.com

About six months of TJs. God Bless America, Bill O|||||||O mailto: snipped-for-privacy@aol.com

No spark. If the CPS is bad the ignition doesn't know that the engine is turning over and so wouldn't know when to deliver a spark. At least for the `89 Cherokee I6 this also meant no error codes, since the computer didn't know that the engine was trying to start.

Yes, that is a symptom for sure. If the body doesn't have a strong ground. the computer won't turn on and you will have no spark and no codes. It has happened to me and tons others here who live int he rust belt.

You can try a booster cable from the battery negative to the body metal to see if it then fires up.

Check those computer ground wires by the dipstick, maybe one got hit during the last service.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's - Gone to the rust pile... Canadian Off Road Trips Photos: Non members can still view! Jan/06 (More Off Road album links at bottom of the view page)