Doesn't re-start when hot

[theK.G.B]

I have a 95 disco and it's it's started to not re-start after turning it off. When the engine cools down for 20 to 30 mins with tue good up it's starts and drives away no problem untill the next time I turned it off. Also I noticed that if I leave it idling for a while when you drive away and get past 2000 rpm in any gear it starts to stutter like miss fires. And insight would be great. I think it may be the ignigtion amp and heat seat causing the problem? Maybe a heat sensitive part? It's mounted right next to the radiator which is very hot during running( duh )
Thanks

 

[ptschram]

That's not nearly as hot as it would be if it were on the side of the distributor, they put it there to keep it cooler.

Check your fuel pressure, my money's on injectors.

 

[thejaw77]

Are you actually getting misfire codes or does it just feel like misfiring? When you turn the ignition to position 2 can you hear the fuel pump turn on? It will be a quite humming or buzzing sound coming from the rear when your in the cabin of the vehicle. If you don't hear anything when trying to restart the truck after operation then you know it is the fuel pump. A sign that the pump is failing is it will hesitate or stumble. If your fuel pump is overheating you will have to wait 20-30 mins until operation can be reinstated.

 

[thejaw77]

Also, if the pumps filtering mechanism get clogged with impurities the engine will show signs of rough firing. Injectors need constant pressure. If fuel isn't pumped constantly and smoothly signs of hesitant start and stumbling problem on ignition will be the result.

 

[RoverbyProxy]

Sure sounds like the fuel pump is going out. I would test power at the pump when it acts up to verify, if power ok and pump no workie then you know. If no power then check the relay.

 

[theK.G.B]

Ok so the fuel pump is coming on at all times! You can smell gas after cranking it over a few times. Tho I did discover I'm losing spark when the engine is hot. But only after it's been shut off. And I don't believe it's the fuel pump getting to hot. Because it won't start for a few hours if you leave the hood closed andbkeep tue heat in. I blew compressed air onto the ignition coil is also near the amp and kablamo! She started???? Do I need to move the coil and heat sink assembly closer to the air intake box

 

[theK.G.B]

Thanks for the advice so far it's sure helping me get to the bottom of this

 

[DarylJ]

Tho I did discover I'm losing spark when the engine is hot. But only after it's been shut off.

Classic hall sensor failure.

That would be crank position sensor in Rover speak.

Good news - it's cheap and easy to replace.

 

[thejaw77]

Does the vehicle stall or shut down without warning during operation? Or does it not restart after primary operation? Do you have a CEL?

 

[thejaw77]

The fuel pump may still come on, but may be weak. Do you get misfire at highway speed? Does it lose power, then regain power when you press the accelerator? Does it have trouble climbing hills? Fuel pump failing symptoms....misfire, delayed acceleration, vehicle won't start, runs intermittently, trouble climbing hills. Not that I'm ruling out the crank position sensor, but that sensor failing causes the vehicle to shut down during operation without warning?

 

[thejaw77]

Does it crank slow? Is there a clicking sound when you try to start it? Bad starter?

 

[messar]

Same problem with a TD4 freelander - would start fine in the morning, but try after it was hot, no start. Was the cam position sensor.

You may want to try some component cooler from Radio shack - get the engine so it won't start, then cool down the component you think might be causing the problem.

Matt

 

[robertf]

Classic hall sensor failure.

That would be crank position sensor in Rover speak.

Good news - it's cheap and easy to replace.

Its a 95, doesn't have one.

 

[theK.G.B]

I try to post a pic of the trouble area. From all the humming a hawwing I did with the multi meter and a few listen here unplug this and that. I noticed when hot the only parts that need to he cool is the ignition coil and the electronic just below it. I'm not sure what it is. I had to call it a night. My land rover is turning me into a wrench handy dude in no time and (robertf) is there a difference between a crank sensor and a crank position sensor. I only ask cause a mechanic I try to fix the issue said he replaced the crank sensor....... Hoping he didn't just make that crap up

 

[DarylJ]

Its a 95, doesn't have one.

Damn combined DI/DII forums.

If anyone ever sees me making any comment about anything DI, just ignore me because I sure as hell didn't mean to.

 

[ptschram]

Have we confirmed presence/absence of fuel pressure and spark at the coil and at the plugs?

We can run around the barn, or we can zero in on the problem and fix the truck.

But, if you guys are enjoying running around the barn, I'll sit back and watch.

No-Start. Step One, check fuel pressure. Step Two, check for presence/absence of spark.

Sheesh, kids these days, got to be led by the hand. Shoulda grabbed 'em by the ear.

 

[tomelroy]

when its hot and wont start have you tried holding the throttle to the floor and turning it over? If it will start with full throttle it may be leaky injectors. My 95 classic had similar symptoms you are having and after replacing the coil, ignition amp, cap and rotor, etc new injectors solved the problem.

 

[robertf]

is there a difference between a crank sensor and a crank position sensor. I only ask cause a mechanic I try to fix the issue said he replaced the crank sensor....... Hoping he didn't just make that crap up

you were lied to

 

[theK.G.B]

Ok so this is I what I know. When the problem is occurring I get no codes, I have fuel pressure. I have no spark at the ignition coil. This problem only happens after I shut off the Vehical at normal running temperature.
If I leave it idling or I'm driving in heavy traffic and the engine bay is I
At it hottest it starts to misfire after 2000 rpm. I have come to notice that the area round the ignition coil which in my disco is mounted to the immediat right of the radiator by the air intake box. When that area is rapidly cooled the Vehical instantly start and drives away...... Now I WILL NOT have the problem again untill the next time the Vehical is shut off and still hot. I gotta have it fixed before summer

 

[ptschram]

I give up. You should pay someone to fix your truck.