I have a 96 DI with 125K. Had for 10yrs.

Recently replaced both engine and alarm ecu's (along with lots of other stuff). After that, truck ran better than it has in years, well for atleast 1000 miles.

Started one fine Christmas morning and stumbled quite a bit then quit.

Very similar to crank sensor. Replaced both sensors (cam and crank) plus fuel pump which was on the way out anyway.

Have spark, and fuel psi. Fuel odor after many crank attempts.

Will occasionally "hit" but not start.

Any ideas out there?

 

The fuel smell is from it being flooded after cranking. I dont think that you are getting spark to all cylinders, or the spark is very weak.
The only reason it wont fire is no spark, you already replaced the crank sensor.
Idle control valve will not let it idle but will let it start and run, just has to be kept above 600 rpm.
When you checked for spark you checked all 8? Do you have a cap and rotor or coil pack? My '97 has the coil pack not sure what year they dropped the cap and rotor.
Did you check the tire pressure? Sometimes that will make it not run.

 

What do your plugs look like? If your pump was going out and you had any water, it could have fouled your plugs.

Do you have a check engine light on?

 

Thanks for the response.

Oh snap...forgot to check the tire psi!!

The plugs are all new, but have to admit I was too lazy to try all the plugs for spark. I will go back and check.

Will try to pull codes on Friday. Prior to replacing the computers, I did have an intermittant crank sensor code which led me to believe the sensor finally failed.

I do suppose it is possible the coil pack could be the issue, just tired of throwing expensive parts at it. I did have a bad wire just after I fixed the computer. Ran fine after the wire/plugs but wonder if I could have weakend a failing coil. Not sure exactly how to check the voltage and assume the voltages will vary depending on start/run cycles if a coil is in fact going bad.

Truck has had yet another 2+ month vacation in the sudo-warm garage. The fuel odor is a bit stale (noticed changing the pump). My wife thought I was using spray paint/varnish! Will check that too.

 

I believe that coils put out the same volts no matter what, spark is spark and you need the most spark no matter what.
I do not know how to check the voltage of a coil. So you have a single coil going to a cap and rotor then?

 

I think checking the voltage without actually cranking can give false indications. As I understand it,a badcoil may show proper voltage until it is actually firing/and drop offduring cranking resulting in insufficient pressure (weak/no spark). Could be off, but I think this may be my problem just kind of difficult to check during this cycle without testbook.

 

You can get testers that will read through the wires, and testers that hook in-line with your plugs. What plugs and wires did you go with?

Might also check all of your vacuum lines. Take the TPS and IAC valve out and clean, along with cleaning your throttle body. Also check the connections to your MAF and inspect it to make sure nothing is in it. DO NOT TRY TO CLEAN. They are $600 a pop and you don't want to kill it. Mine runs like that with the MAF unplugged.

Also , the same about re-checking all of your ECU connections and adding stabiliser to your fuel.

SPIKE : The Discovery's got coil packs in 96.

 

OK, I wasnt sure what year they switched from coil to coil packs and he just kept saying coil.

 

It sounds like the timing chain may have jumped a tooth or two.
You said that you have spark, it sounds like its at the wrong time,, so no starting.

 

I had the front cover off to fix a water leak recently and the timing gear/chain looked fine with less visible wear than vehicles I have had apart with a lot less miles.

Timing unfortunately is exactly what it sounds like.

Problem two is I have had difficulty starting for a while now, and had a weird start ritual where I would have to short crank, reset key position and then start just fine. Actually, the truck would struggle through a start after only a quick hit with the starter/release....Weird=Rover[&:]

I suppose checking the output at the spark plugs sounds reasonable (the spark was a weak yellow color)