4.0 Engine problems

4.0 Engine problems


1978 Jeep CJ5 Renegade, 1970 Kaiser Jeep J2000
Renegade has a slightly modified 304-bored .30 over B&B.
J2000 is stock right now with the Dauntless 350, 4 spd.
My 4.0 fuel injected engine began acting up a week or so ago. At first it would be hard to start and then act like it was cutting out a litle bit.

I changed the plugs the other day and now it will be going along fine and then it will cut out and sometimes comletely off and in a few minutes it will start again.

When it does this you can smell gas almost like when you would flood a carb. except it is fuel injected.

Anyone have any ideas on what this may be?
My first guess when the 4.0 starts to cut out or stall when warm is the crank position sensor located on the upper left side of the transmission housing. It is always good to know when the last time it was replaced, they are somewhat of an Achille's Heel. From what I understand the cam position sensor located under the distributor has similar symptoms, but usually will last a bit longer. The crank position sensor is a magnet that can attract metal particles from the starter engaging the flex plate that can create problems.
Thanks TorxHead. I appreciate that information. The cam position sensor under the distributor you mentioned, is it under the distributor cap or under the distributor itsself somewhere?

I have seen two different portrayals of the cam position sensor being removed. One you did not have to remove the shaft and drive gear and the other you did.
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I replaced the Crank Positioning Sensor yesterday (Thurs.). I had already changed plugs.

After changing the sensor the engine seemed to run great. I drove it about 12 miles or so.

Then I heard a noise and then the belt broke. One of the idler pulleys had come apart and therefore threw the belt an shredded it.

I had a pulley and a belt delivered to me. Got 'er all put back together and she run smooth as silk... for about 8 miles. Then the cutting out began again and it got real bad. So I just had it towed.

While looking it over this morning I noticed the new belt was shreddeda little. It was up over the edge of the power steering pulley past the first rib on the belt so I though maybe I had slipped it over while tightning the tensioner.

Upon closer inspection I noticed the pulley on the crankshaft looked to be slid forward about 1/2 inch or so??

What can cause that? Pulley working loose maybe? I don't know yet if it is loose or not, is that possible?

Now I have both problems!! I ordered a new distributor set up today but if I have some sort of crankshaft problem I may not bother with it.

Any further ideas?

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