Topic: wont start (Read 8426 times)

jeff · « **on:** September 19, 2007, 08:27:12 PM »

Hi. Hope someone out there can help, 97 xj 4.0 auto aw4 lpgd, jeep will not fire , engine is spinning over just will not fire up, no spark, changed crankshaft sensor (again),swapped over asd relays, tried different coil, no power to coil ,So my question is can the camshaft sensor be causing this no spark/ all the lights light up in dash, immobilizer light goes out when cranking, i am stumped can anyone help thanks .

Bubba · « **Reply #1 on:** September 19, 2007, 08:30:43 PM »

cam sensors do some strange shit i think that may well be the problem the xj posse will be along shortly to confirm i am sure

jeff · « **Reply #2 on:** September 20, 2007, 12:19:56 AM »

cheers bubba, i hope so

GermanXJ · « **Reply #3 on:** September 21, 2007, 07:01:12 AM »

Friend of mine had the same prob two days ago it was the Crank pos sensor. Unhook the bat when you hook the new one up.

jeff · « **Reply #4 on:** September 21, 2007, 06:19:17 PM »

just tried that with the battery, jeep still wont fire, When i am cranking there is power going to the coil via the grey lead ,The only other lead going to the coil greeny blue wire with reddy brown tracer ( I am good with colours) appears dead is this right? I thought one of these wires is suppose to be some sort of trigger! could this be the problem? could this be the wire from the cam sensor input which acts as the trigger? or am i way out on this, Any one out there who understands all this stuff?

chrisjones · « **Reply #5 on:** September 21, 2007, 09:12:13 PM »

My money would be on the crank position sensor.

They're about 70 holes from Jeep (I think). (Worth having a spare in the tool box anyway. :wink:

)

jeff · « **Reply #6 on:** September 21, 2007, 09:48:25 PM »

Hi Chris, I have already put new crank sensor on but still the jeep wont fire up.Thats why i am thinking could it be the cam sensor?

Mike Pavelin · « **Reply #7 on:** September 21, 2007, 10:06:37 PM »

Have you checked for fault codes?

jeff · « **Reply #8 on:** September 21, 2007, 10:32:34 PM »

Hi Mike,No, I havent got a code reader,when i turn key to on all the lights in cluster go out including check engine light as they should so i presumed there are no codes , is this correct ? was looking at code readers on ebay for about £30 are these any good?

wazza · « **Reply #9 on:** September 21, 2007, 11:21:23 PM »

for checking the codes, turn the ignition on an off three times then leaving it on an the engine warning light will flash, chech the hayns manuall for what they mean. (i cant remember right now) but ill fid out if you need.

i'd put money on crank sensor aswell, the trigger wire your on about gets its signal via the ecu via the crank sensor the cam sensor ties in with it but shouldn't prove a problem, its not something ive every heard of.

about a month ago i sold a cherry i didn't like to a friend an the crank sensor went, he changed it for one from light house jeep parts an still no start, so myself an another auto electrician went over the whole lot an it came back to a faulty crank sensor, he phoned up light house an all they said was "oh yer that will be the third we've had returned out the same batch" so he got one from the jeep stealership an it fired straight away.

befor people start bashing me i like light house an theyve always been good for my parts but thats what happened with my friend.

so take your crank sensor bvack say its faulty an get another, then if that doesn't work then your looking for something else.

Mike Pavelin · « **Reply #10 on:** September 21, 2007, 11:23:00 PM »

Try this..... http://www.go.jeep-xj.info/HowtoECUcodes.htm

Otherwise you'll need a scanner.

jeff · « **Reply #11 on:** September 22, 2007, 12:12:59 AM »

I have tried to access the codes before without any luck mine is the facelift model obd2 i think i will need a scanner. I put the crank sensor on the jeep from the stealership 4 months ago when the jeep had the same symptoms it cured it then, so when it wouldnt start again this time i automaticaly thought the sensor had packed in so i took a chance and ordered another from stealership(£115) put it on and still the same it has no spark . if my check engine light goes out does that mean there are no codes stored in ecu?

Mike Pavelin · « **Reply #12 on:** September 22, 2007, 08:11:51 AM »

Have you tried cycling the key 4 times instead of 3? If you can't get it to work

The check engine light is only in self test when you turn the ignition on. It should come on then go off and stay off until the engine starts. Then if there are active codes (i.e. the fault is present right at that moment or since the last start and it is a serious fault) the engine light will illuminate, but only when the engine is actually running. If the code is historical (not present since the last start or not serious) it will not.

If there is an electrical fault causing the non start, The system will usually log a fault. Retrieving tha fault codes can give an indication of the problem, but remember that code is only a starting point and doesn't gaurantee the component identified is the actual root cause.

jeff · « **Reply #13 on:** September 22, 2007, 08:57:29 AM »

mike,just tried cycling key 3,4,5, times with same result dials move gauges light up then go out odometre counts down from 11111 to 99999 then thats it, no codes .bloody thing :cry:

Bubba · « **Reply #14 on:** September 22, 2007, 10:16:59 AM »

no bashing here i have had duff parts for mercs rollers and most of the rest over the years

Mike Pavelin · « **Reply #15 on:** September 22, 2007, 10:46:46 AM »

Looks like you'll have to get it scanned then.

jeff · « **Reply #16 on:** September 25, 2007, 06:52:16 PM »

Right, Scanner came today (u480) plugged it in and there was one code p0700 on top line of display and 01/01 on second line of display,(hope this isnt date).700 code on list i got off tinternet says the automatic transmission computer or aisin computer has a problem, Can anyone make any sense of this!! :cry:

dtooth · « **Reply #17 on:** September 26, 2007, 11:09:26 AM »

is it the neutral switch on the autobox ?

Mort · « **Reply #18 on:** September 26, 2007, 04:52:32 PM »

Quote from: "dtooth"

is it the neutral switch on the autobox ?

I was gonna suggest that too. Do your reversing lights work OK, and can you get your XJ to start by jiggling the auto shift lever?

JamesH · « **Reply #19 on:** September 26, 2007, 06:08:24 PM »

Mine's a bit dodgy at the moment. It will start if I gently pull it back to the rearmost part of the PARK position.

However, the engine won't turn over at all until it hits the right spot so sounds a bit different from these symptoms??!?

The auto transmission (Aisin AW4) has it's own controller/computer but I've never heard of faults with it.

tag · « **Reply #20 on:** September 26, 2007, 06:23:09 PM »

Hi, i'm a bit late reading this thread but if you want to test your crank position sensor use a multi meter set to mV connect the leads to the 2 wires( poke the probes into the plug) it's better if you have it off the car, then wave something metal very close to the sensor you should get a reading each time you pass the probe head, i used a screw driver the probes magnetic so it's a bit tricky as the driver wants to stick to the probe. the probe is a hall effect device which produces a small voltage. hope this helps........

jeff · « **Reply #21 on:** September 26, 2007, 06:57:00 PM »

The engine wont crank unless lever is in P or N, My reversing lights have always worked, I think they only operate when engine is running, put lever in R and turned the ignition to on they did not light up i think this is right? :cry:

Mort · « **Reply #22 on:** September 26, 2007, 09:37:55 PM »

Trish's XJ's reversing lights come on with the ignition turned on, but the engine not running................. or rather they did until the bl**dy NSS switch started playing up. :roll:

jeff · « **Reply #23 on:** September 27, 2007, 05:18:26 PM »

Does the NSS stop the engine cranking? cause my engine is cranking but just not firing :cry:

Mort · « **Reply #24 on:** September 27, 2007, 06:23:04 PM »

I've only had a problem with the reverse lights, not starting issues, but my understanding is that the engine wouldn't crank if the NSS was faulty, you'd just turn the key and nothing would happen - but jiggling the auto shift can sometimes cause things to spring into life.

Author Topic: wont start (Read 8426 times)

jeff

jeff

GermanXJ

jeff

jeff

Mike Pavelin

jeff

wazza

Mike Pavelin

jeff

Mike Pavelin

jeff

Mike Pavelin

jeff

dtooth

Mort

tag

jeff

Mort

jeff

Mort