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Going nuts!!!

M

mrtosh

NAXJA Forum User
Location
Woodbury, MN
Alright, starting to go a little nuts here. I've been on the forum researching this problem for hours on end. My '94 starts up perfect on cold starts and after letting sit for 5-10 mins. Let it sit for 1/2 hour to 3 hours, and it's crank, crank, crank, sputter and fire. If you hold the peddle to the floor it'll fire up a little faster. I'm thinking it's a spark problem, seeing as how flooring it shuts off fuel to the injectors. I did do a tune-up on it(plugs, wires, cap, rotor) which took roughly 20-30 mins. In which in would usually take a while to fire up. It fired right up like on cold starts.. :weird: Drive it around for a while, park it, go to start it an hour later, same thing.... Could it be gases from the crank case coming up and getting moisture in the cap, and evaporating over night so it starts easier in the morning? Or possibly a sensor? It runs awesome once running. Any help would be greatly appreciated.

Thanks guys.
 
try some seafoam thru the tank. it kinda sounds like you got leaky/cracked/clogged injectors.you should NEVER EVER floor a fuel injected vehicle when not actually running.:scottm:
 
a7273chargerguy said:
hell, i don't know i have just always heard that:laugh3:
Click to expand...

There's nothing harmful or wrong about flooring it. It's just that doing it will generally have no effect on starting, as it did back in carburetor days. A carburetor usually has an accelerator pump, which actually squirts a bit of gas down the manifold, and if there's an automatic choke, you must also floor the pedal once before starting to set it correctly. Neither of these things will happen with FI. However, if your engine is flooded, it can help to open the throttle to provide more intake air, and that is independent of whether you have FI or a carb. All of which is the long winded way of saying that if flooring it helps, I would look for something, such as a leaky injector, that is causing flooding, rather than something that is causing leanness.

However, I would also suggest that you check the ignition system again. There's a long shot chance that a bad coil could be causing hot start problems.

I wouldn't expect moisture or vapors in the distributor to be the issue here, since there are no points to foul, but I guess anything is possible.
 
Matthew Currie said:
There's nothing harmful or wrong about flooring it. It's just that doing it will generally have no effect on starting, as it did back in carburetor days. A carburetor usually has an accelerator pump, which actually squirts a bit of gas down the manifold, and if there's an automatic choke, you must also floor the pedal once before starting to set it correctly. Neither of these things will happen with FI. However, if your engine is flooded, it can help to open the throttle to provide more intake air, and that is independent of whether you have FI or a carb. All of which is the long winded way of saying that if flooring it helps, I would look for something, such as a leaky injector, that is causing flooding, rather than something that is causing leanness.

However, I would also suggest that you check the ignition system again. There's a long shot chance that a bad coil could be causing hot start problems.

I wouldn't expect moisture or vapors in the distributor to be the issue here, since there are no points to foul, but I guess anything is possible.
Click to expand...

Not to sound like a noob, but what would be the best way to check the coil and test for leaky injectors??
 
Have you taken the dizzy cap off to check for moister when it doesn't fire up?
I'm thinking CPS. The same symptons mine had. CPS cured it. Check the connection first.
 
Just an idea but my Ford truck did the same thing. And it was the distributor. When it would get warm after starting the engine it would become loose for some reason so when I went to start it again it would make the timing off and I would have to let the motor cool till I could move the truck.
 
After steam cleaning or pressure washing the eng you will most always get condensation in the dist cap and that will create spark running around in the cap causing misfires.

I carried a can of starter fluid and would pull the cap off and spray the inside then let lt dry out before before replacing the cap.

Replacing it too soon and cranking the eng can cause a small explosion and cap will be in several pieces.
 
Do a search on here about "heat soak".

By the way, holding the accellerator all the way down on an XJ triggers the computer to turn off the injectors during a start.
 
To check the Coil, Pull the center wire from the dist cap, leaving it plugged in the coil.

Have someone crank the eng over while holding the end of the wire within 1/4" of a good ground. there should be a nice blue spark.
a orange spark could be a weak coil.
 
Definatly check cps, on mine almost all no-starts have been caused by a cps going out, i guess i have really bad luck when it comes to those things.
 
parkeruph said:
Have you taken the dizzy cap off to check for moister when it doesn't fire up?
I'm thinking CPS. The same symptons mine had. CPS cured it. Check the connection first.
Click to expand...

Well, it's been around 8 below (w/out windsheild!!) here in good 'ol Minnesota, so it's been starting great no matter how long it's been sitting. I started it today drove it around let it sit to the point where it would usually take a while to start and it fired right up!?! Soo, I'm guessing it def. is a heat issue. Either the CPS is acting goofy when warm, moisture in the distributor cap, or weak coil when warm. Don't think it has anything to do w/the injectors? I did check the cap today when it was warm. Granted it's freezing outside, it looked fine. The rotor was a lil brown on the tip, but that was it. If there was moisture in the cap, what would be the best way to fix it? The CCV works fine..
 
The CPS will do goofy things over a period of years. Mine had a seperated wire inside the

insulation. Worked for long periods of time, then not, I replaced the pickup coil inside the

dist. Disconnected the battery to reset the PCM and drove it 7 miles and the CPS quit for good.

CPS's are intermmittent and act goofy enough to screw up a diagnosis.

Hope you find the problem before it leaves you stranded in a NO CELLPHONE SERVICE AREA.
 
Looks like i might change out the CPS, give that a try. Any tips or tricks to getting to those two lil buggers on the bell housing?
 
If it is fairly easy to get under, It's easier if you crawl under from pass side, it is easier to get your arms and hands in the corrct position, you may have to jack it up and put jack stands under it.

U will need a 18" extension and a 11 or 12mm socket, I forget, getting old, Thats what it took on my 93XJ.
 
For CPS replacement, I did best with a 1/4 inch drive ratchet, a couple of long extensions, a medium extension and a U-joint. Different combinations of parts for each bolt. Use a magnetic insert in the socket if possible, or just stick a little piece of paper into the socket before you insert the bolt head, so it stays in.

If at all possible, use the plastic dust shield that snaps into the bell housing. It will keep the CPS in place so you don't have to hold it there while you are trying to feed in the bolts.

Make sure you have lots of light.
 
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