[nanasjeep]

OK, Here's what happened.

Please note prior to this, there were no issues with the car. it has 200,000km and is well maintained and serviced regularly.

Jeep started to sputter, run rough and died in the driveway.

Got it started and into the garage.

After looking around, discovered that the tab that holds the distributor in BROKE and the distributor had "popped" up.

Bought new distributor, installed it. Made sure timing was in correct spot.

now come the issues......

- it is VERY hard to start. it cranks and after 2nd or 3rd try it does start

- when it starts, it runs VERY rough sputtering and coughing and the odd backfire

- the exhaust starts to glow after 8-10 minutes? ( yes we shut it off as soon as it started to do that)

- checked (tested) the wires going to the injectors and they are fine

- pulled plugs and they are BLACK

- checked fuel rail and there is pressure but not sure how much

- fuel pump can be heard upon turning the key forward so we are assuming it functions.

- Check Engine light did not come on and it still does not come on.


Anyway, I think that's it. we are STUMPED why is it running so rough? the only thing that was "touched" is the distributor.

ANY THOUGHTS / SUGGESTIONS WOULD BE VERY GRATEFULLY ACCEPTED !!!

[PDBreske]

My first instinct would be to check that the plug wires are indeed in the same order now as they were before you replaced the distributor. It sounds like they were reconnected in the wrong order to the dist. cap (or at least some of them are out of order) leading to some cylinders firing correctly and some not firing at the end of the compression stroke. The exhaust manifold might overheat if the unfired cylinders are dumping their unburned fuel into the exhaust, which is then ignited by the exhaust of the other cylinders. This would also explain the backfiring if the plug was firing during the intake stroke.

Or maybe I'm way off. Anyone else have any guesses?

[nanasjeep]

Originally Posted by PDBreske

My first instinct would be to check that the plug wires are indeed in the same order now as they were before you replaced the distributor. It sounds like they were reconnected in the wrong order to the dist. cap (or at least some of them are out of order) leading to some cylinders firing correctly and some not firing at the end of the compression stroke. The exhaust manifold might overheat if the unfired cylinders are dumping their unburned fuel into the exhaust, which is then ignited by the exhaust of the other cylinders. This would also explain the backfiring if the plug was firing during the intake stroke.

Or maybe I'm way off. Anyone else have any guesses?

I'm pretty sure that they are on the correct spots but we'll check just to be sure. They were changed 1 at a time from the old dist to the new one but hey you never know.

Is there a way to tell if an injector is bad? could that cause these issues? It almost seems like it's not getting enough fuel.

If you rev it up to about 1500rpm it runs better. It's the idle and initial starting that seem to very troublesome. As soon as you let the idel fall back down, it sputters and dies

[PDBreske]

Originally Posted by nanasjeep

I'm pretty sure that they are on the correct spots but we'll check just to be sure. They were changed 1 at a time from the old dist to the new one but hey you never know.

Is there a way to tell if an injector is bad? could that cause these issues? It almost seems like it's not getting enough fuel.

If you rev it up to about 1500rpm it runs better. It's the idle and initial starting that seem to very troublesome. As soon as you let the idel fall back down, it sputters and dies

Oh, well, you didn't mention the "runs better" part. LOL

In that case, it can't be the plugs wires out of order. Maybe the timing is off. Did you use a timing light on the crank after installing the new distributor or just line it up where the old one was? It doesn't take much for the timing to be way off, but the timing changes as the engine RPMs increase, so maybe that's why it would run better at speed and rough at idle.

[SkinnyMe97]

Timing is computer controlled . Best guess is you dist. is a tooth or two off .

[nanasjeep]

Originally Posted by SkinnyMe97

Timing is computer controlled . Best guess is you dist. is a tooth or two off .

OK, so what's the fix for that other than trial and error?

OH one more thing, After firing it up, the exhast spit out some damp black crap. And it smelled funny. Don't ask me to describe funny as i really can't. But it didn;t smell right.

Would it run like crap and have a hard time starting if it was off a tooth or two?

We suspect some sort of fuel issue ( possibly not enough) due to the plugs / crappy idle / and hard to start.

[SkinnyMe97]

OK, so what's the fix for that other than trial and error?

Yeah . Sounds like the dist. is set back a couple of teeth causing the timing to be retarded , as the RPM's icrease and the computer advances the timing it would smooth out .

[PDBreske]

Originally Posted by nanasjeep

OK, so what's the fix for that other than trial and error?

You don't have to remove and reinstall it (although you could if you want to). All you need to do is loosen the locking bolt and rotate the distributor until the timing is set to where it should be. You'll need to use a timing light to get it right.

The good news is it's close right now. If it was too far off the engine wouldn't run at all.

[SkinnyMe97]

There is no locking bolt and the dist does not rotate as I said before timing is comp. controlled .

[jeeptorino68]

its a tooth off i bet, we just had the same troubles with the 91, really hard to get started, and it seemed like we had it in there fine, but we didnt
you can turn the crank shaft really easy from under the jeep with a 19mm socket, get it to 1TDC and try again

[PDBreske]

Originally Posted by SkinnyMe97

There is no locking bolt and the dist does not rotate as I said before timing is comp. controlled .

Oh. Never mind me. I'm just going on what I know of distributors in general.

[SkinnyMe97]

Originally Posted by PDBreske

Oh. Never mind me. I'm just going on what I know of distributors in general.

Yeah, no biggie.

[nanasjeep]

we did the 1tdc thing.

today we will try to pull exhaust to see if something in there is plugged. also putting in new o2 sensor. 200,000 km and all.... we don't thing it has ever been changed anyway.